chemistryy
What is the formula of ammonium phosphide?
(NH4)3P
What is the net charge of an ion (charged atom) if it has 7 protons and 10 electrons?
-3
What is the % abundance of Boron -12?
0%
I've decided that I want to have some orange juice, but my teeth are very sensitive to acidic drinks. In order to make it less acidic, I need to raise the pH 0.5 units higher. How much water do I need to add to dilute 0.2 L of my juice to the desired pH level?
0.42
Relate the three units of pressure
1 atmosphere = 101,325 Pascal = 760 torr
Balance the following: ___H2+ ____Br2 à _____HBr
1,1,2
Balance the following: ____KC1O4 à ____KC1 + ____O2
1,1,2
Balance the following: ____Cl2 +____KI à ____KC1 + ____I2
1,2,2,1
How do you manage to create a saturated solution from the solution in the dispenser? (There might be more than one correct answer)
1. Add certain volume of the dispenser's solution to the solvent (water) in the beaker, then evaporate the solvent until you reach saturation. 2. Empty the beaker from the water, add certain volume of the dispenser's solution, then evaporate the solvent until you reach saturation.
Explore the various ways you can reach saturation from 1.00 mole/Liter concentration.(There might be more than one correct answer)
1. Adding more solute until reaching the saturation point 2. Evaporating the solvent (water) until reaching the saturation point
Why does the field of organic chemistry focus on Carbon? (There might be more than one answer)
1. Carbon forms four covalent bonds, which give it great flexibility in bonding 2. Carbon makes fairly strong bonds with itself, which allows the formation of large molecules 3. Carbon forms strong bonds with other elements, which allows the formation of variety of substances.
Is the above process physical or chemical changes? What are your evidences? ( There mi
1. Chemical change, where we formed new substance as evidenced by the light and heat produced. 2.Chemical change, where we formed new substance as evidenced by the color and luster change.
What is the source of SO2 pollutant in our atmosphere? (there might be more than one correct answer)
1. Coal combustion 2.Copper smelting
What is unique about gases, in contrast to solids and liquids? (There may be more than one answer)
1. Gases have no definite shape or volume 2. Combinations of gases always form a solution 3. Gases can compress and expand
The secondary pollutant(s) associated with photochemical smog that cause both eye irritation and potential lung damage is/are ______________ (There might be more than one correct answer
1. PANs 2. Ozone
Smog formation will continue to increase as urban growth occurs across the world. State ways to decrease smog formation in areas that are prone to it. (There might be more than one correct answer)
1. Switch from fossil fuels to greener energy sources 2. Regulations on vehicle emissions and gas content 3. Regulations that ban burning coal in certain areas of the city
Biological variation such as _____________________ influence the degree of poisoning caused by a chemical. (There could be more than one answer)
1. age 2. gender 3. individual susceptibility
There is less risk of chemically caused harm if the human body can do the following to the chemical ________________ (there could be more than one answer)
1. break down the chemical into less harmful chemicals. 2. rapidly remove the chemical from the body.
Radiation is _______________, with its source being the radioactive nuclei . (There might be more than on answer)
1. electromagnetic rays 2. sub-atomic particles
Adding an indicator to a base solution changes the color of the base solution to _______________ (there could be more than one answer)
1. yellow/bright green 2. green/blue
Determine the concentration value of the copper sulfate solution in the dispenser (in mol/Lite
1.00
Carefully, add more Copper Sulfate until you reach the saturation point.What is the concentration value in mol/Liter?
1.380
The half-life of 60Sr is 28 y. What fraction of a sample of 60Sr will remain after 56 y have elapsed?
1/4
After three half-lives have elapsed, what fraction of the original amount of radionuclide remains?
1/8
The half-life of 60Co is 5.3 y. About how long does it take for 3/4 of a sample of that radionuclide to decay?
10.6y
Balance the following: ____HCl + ____ZnS à ____ZnCl2 + ____H2S
2,1,1,1
Balance the following: ____Mg + ____CO2 à ____C + ____MgO
2,1,1,2
Balance the following: __Zn + __O2 à __ZnO
2,1,2
Balance the following: ____Na + ____Cl2 à ____NaCl
2,1,2
Balance the following: ____SO2 + ____O2 à ____SO3
2,1,2
Balance the following: __Fe + __Cl2 à __FeC13
2,3,2
Balance the following: ____Ag2O à ____Ag + ____O2
2,4,1
(Syllabus Question) What is the course policy regarding late submissions?
20% penalty per day
Define saturated, unsaturated, and supersaturated solutions
Saturated solution is formed when the maximum amount of solute has been dissolved in a given amount of solvent. Unsaturated solution is formed when less than the maximum amount of solute is dissolved in a given amount of solvent. Supersaturated solution is formed when more than the maximum amount of a solute in dissolved in a given amount of solvent.
Which of the following are molecules (covalent compounds) ? (There might be more than one answer)
SeCl2 CO2
What mean is used to solve the problem of water pollution as a result of mining of ores and the subsequent processing with water discharge of fine silt with toxic metals into waterways?
Sedimentation
What is a polyatomic ion?
Several atoms bonded to each other and forming a net charge
Given the following ions: Ag+ and SO42− What is the name of the ionic compound formed between them?
Silver sulfate
The pollutions' problems which currently overshadow any other pollution problem are all the following EXCEPT _________
Smog and photochemical smog
The stronger the intermolecular forces the more likely that the phase of the matter will be
Solid
The difference of properties among the Phases of Matter, in terms of compressibility, are
Solids and liquids are lightly compressible, while gas is highly compressible.
The difference of properties among the Phases of Matter, in terms of density, are
Solids and liquids have high density, while gas has low density.
The difference of properties among the Phases of Matter, in terms of shape, are _____________________
Solids are rigid, while liquid fills a container from bottom to top. Gas, on the other hand, fills entire container.
All the following statements related to solid properties are TRUE except
Solids vary in shape depending on the container they are placed in
What do we mean by: "solubility of ionic compounds is a matter of degree"? (there could be more than one correct answer)
Some ionic compounds are very soluble, some are only moderately soluble, and some are soluble so little that they are considered insoluble. For most ionic compounds, there is a limit to the amount of compound can be dissolved in a sample of water.
Kinetic energy is associated with
Speed
Given the following ions: Sr2+ and N3− What is the formula of the ionic compound formed between these two ions?
Sr3N2
Conclusion [include the name of the process and the major product(s)]
Sublimation, where solid iodine converts from solid to gas, without passing through the liquid phase
The average speed of an ideal gas' particles depends on _____________
Temperature
How does the concentration change while the water evaporates?
The concentration increases
How does the concentration change while you empty the solution?
The concentration stays the same
After reaching saturation, add more solute. What happens to concentration? What else do you observe?
The concentration stays the same, and solid starts to precipitate at the bottom of the beaker
All of the following are ways to increase the pressure in a container, with the exception of one, which is ___________
Using a different gas size
How many atoms of each element are represented in this formula? 2H2SO4 H =__________ S =__________ O =________
H = 4 , S = 2 , O = 8
What are the chemical symbols of the four major elements of life?
HONC
Radioactive decay was discovered in 1896 by ___________
Henri Becquerel
What types of weather patterns are produced by high pressure and low pressure fronts?
High pressure produces dry weather, while low pressure produces stormy weather
What are the differences between intermolecular forces and intramolecular forces?
Intermolecular forces are forces between molecules while intramolecular forces are forces within molecules
Which radioactive isotope is used for diagnosis and treatment of thyroid function?
Iodine -131
When an atom lose electron(s), it becomes ____________ (there might be multiple answers):
Ion Cation Positively charged
When an atom gain electron(s), it becomes ____________ (there might be multiple answers):
Ion Negatively charged anion
To indicate a particular isotope of Iron that has 30 neutrons, we call it
Iron 56
What is the name of FePO4
Iron(III) phosphate
According to Arrhenius definition of acid, H2SO4(aq) is an acid because
It dissociates causing increase in the H+ concentration in the aqueous solution
According to Arrhenius definition of base, KOH (aq) is a base because
It dissociates causing increase in the hydroxide ion's concentration in the aqueous solution
Why is glass considered solid not liquid?
It does not flow when force is placed on it
A solution is defined as ____________
a homogeneous mixture
What is the toxicity of the chemical?
a measure of the poisoning strength of a chemical
Give the proper formula for nitrogen triiodide
NI3
When the "nutrition facts" of a food you buy from a grocery store states the grams of sodium in it, what type of sodium is it referring to?
NOT: sodium molecule NOT: Sodium negative ion
In the complete ionic equation below, the spectator ions are
Na+(aq) and C2H3O2- (aq)
When a cobalt-60 nucleus undergoes beta decay, the nucleus formed is that of ___________
Nickel-60
What is the proper name of the molecule NO?
Nitrogen monoxide
Which product of incomplete combustion gives photochemical smog its yellowish color?
Nitrous oxide
Are all transition metals variably charged?
No
Are there differences between an adrenaline that was extracted naturally, and an adrenaline that was synthesized in the lab? Explain
No, they both exhibit the same exact chemical composition, structure, and physical and chemical properties.
When we use a pressure gauge to measure a gas pressure in a container (or car tire). The pressure will be maximum at:
None, The pressure is the same throughout the container
The elements on the periodic table are listed in order of ascending __________ (complete) -select all correct answers-
Number of protons atomic number
The main reason salt and sugar dissolve differently is:
One is an ionic compound while the other is a covalent molecule
What is the difference between NO2 and NO2−? (There might be more than one correct answer)
One of them is a neutral molecule while the other is polyatomic ion One of them is nitrogen dioxide while the other is the nitrite polyatomic ion
What are the differences between H2S(aq), and H2S? (There might be more than one correct answer)
One of them is an acid, while the other is a molecule One of them is hydrosulfuric acid while the other is dihydrogen sulfide
The SI-approved unit of pressure is the ___________, which is defined as 1 N/m^2
Pascal
Write the proper ionic formula for the ionic bond between these two ions: O2- and Pb4+
PbO2
Are the above processes physical or chemical changes? What are your evidences?
Physical change as we started with liquid water and solid salt, and ended up with the same.
Conclusion [include the name of the process and the major product(s)] Are the above processes physical or chemical changes? What are your evidences?
Physical change only, solid Iodine sublimed to gas, then deposited back to solid when cooled down.
By looking at the periodic table, which element has atomic number 19?
Potassium
What was the cause of the Hindenburg explosion?
Reaction of Hydrogen (inside the Hindenburg) with oxygen in the atmosphere to form water and flame
Why is the "kinetic theory of gasses" is important even though it deals with ideal gases not real ones?
Real gases deviate slightly from the ideal ones making the theory applicable
What is the role of radioactivity in smoke detectors' function?
a radioactive element ionizes the space between metal plates allowing electric current to go through, when smoke is present the current is disturbed which activates the alarm circuit
Estimates indicate that the proportion of the global burden of disease associated with environmental pollution hazards ranges from _____________________. These estimates include infectious diseases related to drinking water, sanitation, and food hygiene; respiratory diseases related to severe indoor air pollution from biomass burning; and vectorborne diseases with a major environmental component, such as malaria.
25-30%
Pollutant chemicals could be produced by all of the following, EXCEPT ______________
astrological causes
In the periodic table (check the attached periodic table), element's atomic number is stated on the top while mass number is not stated. In a nuclear symbol, however, ________________
atomic number is stated on the bottom while mass number on the top
Isotopes are _____________ (select all correct answers)
atoms with the same number of protons but different numbers of neutrons atoms of the same element that differ in the numbers of neutrons
Is the pH of 0.2L of blood acidic or basic?
basic
An acid is called an acid because of the amount of positive hydrogen ions that are dissolved in the solution. Based on this concept, which substance among the list below has most hydrogen ions dissolved in the solution?
battery acid
Air pollution can cause all of the following, EXCEPT ______________
broken bones
We can control air pollution through all of the following, EXCEPT ___________
burning more fossil fuel
The term "dynamic equilibrium" refers to a situation in which a process still occurs
but the opposite process also occurs at the same rate so that there is no net change in the system.
"Health-related complaints about cosmetics and shampoos at all-time high". All of the following are related to this health problem EXCEPT __________
cosmetic industry limited budget
Which phase of the matter have the highest kinetic energy?
gas
There are 1.4 × 1014 grams of gold in the world's oceans, yet it is not practical to extract gold from the oceans. Why?
gold concentration in the sea water is about 1 part per every 1 × 1013 parts of seawater
In a half milligram (weight of a grain of sand) of an organic compound like epinephrine (adrenaline), the number of molecules is less than the number of _________________ Selected:
grains of sand on earth
A ___________ haze is associated with industrial smog, while a ___________ haze is associated with photochemical smog. Selected:
gray, yellowish
Most ions are more abundant in seawater than they are in blood, with notable exceptions for hydrogen carbonate ions (HCO3−) and hydrogen phosphate ions. There exceptional ions have higher concentration in blood than in seawater because they ____________
have an important role in controlling the acid-base properties of blood.
Neutrons are good "projectiles" for inducing nuclear reactions because they _______
have no electric charge
Many bodily fluids (especially blood) resemble seawater because _________________
it is highly likely that life on Earth originated in the oceans, so blood evolved from seawater
Although Table sugar (sucrose) is a not an ionic compound, it is soluble in water because _________
its polar hydroxyl groups
Some doctors recommend that people with hyper-acidity take magnesium hydroxide because
magnesium hydroxide is basic, so by introducing it to their system they bring the acidity down
From the readings, the modern atomic theory postulates the following (there might be multiple answers):
matter is composed of atoms. Atoms of the same element are the same; atoms of different elements are different Atoms combine in whole-number ratios to form compounds
Which of the following fields would be considered natural science?(There might be multiple correct answers):
meteorology, the study of the climate and weather Mechanics, the study of motion
The following are examples of chronic toxicity EXCEPT _____________
momentarily skin contact with certain organic solvents that are absorbed through the skin may cause dizziness and nausea.
In the scientific method, a hypothesis____________(complete)
must be tested by experiments
All of the following are primary pollutants, EXCEPT ______________
neon
Pressure of a gas is defined as ________________
net Force exerted by the gas particles' collisions per unit area of a container
All of the following are considered major types of radiation, except _________
neutrino
The fission of 235U nuclei is initiated by _________
neutrons
The easiest deadly plant to ingest by accident is __________, because to the untrained eye, its berries might look like blueberries. Eating 10 berries can be enough to kill an adult.
nightshade
Volatile organic compounds include all of the following EXCEPT _________
nitrogen oxide
Which of the following household chemicals is always safe no matter what you mix it with?
none of the above
compounds exist as molecules when ______________
nonmetals chemically bond with other nonmetals
Experiments by Ernest Rutherford in England in the 1910s lead to the discovery of ____________
nucleus
What is the number of protons, mass number, and number of neutrons of H 3 1
number of protons is 1, mass number is 3, and number of neutrons is 2
All of the following are considered Suspended particulate matter (PM) EXCEPT ______
odor
In case two chemicals were mixed accidentally, what should you do immediately?
open the nearest window
Which of these oxygen's isotopes were shaking (radioactive, hence unstable)? Select all the correct answers
oxygen-15 oxygen-19
Which of these oxygen's isotopes exist in nature (Their % abundance is not zero)? Select all the correct answers
oxygen-16 oxygen-17 oxygen-18
a single covalent bond is made of _____________
pair of electrons shared
We know much more about acute toxicity of a chemical than its chronic toxicity, for the following reasons EXCEPT _____________
studies of groups of people occupationally exposed to a chemical for many years
Flour mixed well with water will produce _________________
suspension
The chemical formula NaOH (sodium hydroxide) exists in all of the following household chemical EXCEPT _______________
teflon
When placing an empty hot container, face down, inside cold water container, the water will rise from the water container to the hot empty container because ___________________________
the air pressure inside the empty hot container is less than air pressure outside, causing force to push water from the high pressure area (outside the container) to the low pressure area (inside the container).
When an ionic compound dissolve in water, it will dissociate so that
the cation and the anion of the ionic compound will separate, where the cation will be surrounded by the partially negative water's oxygen, while the anion surrounded by the partially positive water's hydrogens
When molecular compounds, such as sugar, dissolve in water, the individual molecules drift apart from each other. While when ionic compounds dissolving in water, _____________
the individual ions physically separate from each other
When we say that the "collisions between gas particles are elastic", this means ______________
the kinetic energy before collision is equal to the kinetic energy after collision
Given this balanced chemical equation: 2NaI(aq) + Pb(C2H3O2)2(aq) ® PbI2(s) + 2NaC2H3O2(aq) What is the net ionic equation?
2I-(aq) + Pb2+(aq) ®PbI2(s)
Given this balanced chemical equation: 2NaI(aq) + 2 Pb(C2H3O2)2(aq) ®PbI2(s) + 2NaC2H3O2(aq) What is the complete ionic equation?
2Na+(aq) + 2I-(aq) + Pb2+(aq) + 2C2H3O2- (aq) ®PbI2(s) + 2Na+(aq) + 2C2H3O2- (aq)
How many covalent bonds does carbon need?
4
Force of 60 N is exerted by gas particles against 3m x 4 m wall, what is the pressure against that wall in Pascal?
5
What is the % abundance of the isotope, Boron - 11, in nature?
80%
A pressure of 0.887 atm equals how many pascals?
89,875.28
In the following neutralization reaction 2CsOH(aq) + H2SO4(aq), the salt produced will be
Cs2SO4(aq)
How are A (mass number), Z (atomic number), and N (number of neutrons) related?
A = Z + N
MgF2 is an example of ionic bond because _______________ (there might be multiple correct answers)
A metal bonded to non-metal Cation (positive ion) bonded to anion (negative ion)
Which of the following statements is false?
A proton has no charge
What do you know about the "photosynthesis" reaction?
A series of light-dependent and light-independent reactions
What is a molecule? (select all correct answers)
A substance composed of chemically bonded atoms and has unique physical and chemical properties A substance composed of multi-atoms that are chemically bonded and behave as a single particle
What is the name of the following acid: HC2H3O2
Acetic acid
Air is made of the following: 78% nitrogen, 21% oxygen, and 0.9% Argon, and 0.1% other substances (e.g. water vapor, carbon dioxide, ..etc).
Air is a solution, and nitrogen is the solvent
How many atoms of each element are represented in this formula? 4Al2O3
Al = 8 , O = 12
In the equation : Al + P à AlP
Al and P
Given the following ions: Al3+ and OH− What is the formula of the ionic compound formed between these two ions?
Al(OH)3
Write the proper ionic formula for the ionic bond between these two ions: Al3+ and S2−
Al2S3
What is the formula of Aluminum phosphide
AlP
Francium has an atomic number of 87. Francium-212 undergoes an alpha-decay. What is the daughter isotope?
Astatine - 208
Which nuclear fuel is harder to produce, atomic bomb's fuel or nuclear power plants' fuel ? Why?
Atomic bombs are harder because they require 70% or more uranium-235, which makes up only 0.7% of natural uranium, while nuclear reactors require only 3% uranium-235 enrichment.
The number of protons in a nucleus of a Chlorine atom is 17, while the number of neutrons in the nucleus is 20. What are the atomic number and the mass number of this Chlorine isotope?
Atomic number is 17 , while mass number is 37
What is the other isotope of Boron that exist in nature (meaning its % abundance is not zero)? and what is its % abundance?
Boron-10, its abundance is around 20%
How did the small molecules, which were present at the beginning of earth's formation, evolve into long chains of organic molecules?
By rubbing against each other to form new chemical bonds, based on specific mechanism and using the energy of the sun
How many atoms of each element are represented in this formula? 3Ca3(PO4)2
Ca = 9 , P = 6 , O = 24
In the equation: CaCO3 à CaO + CO2 the reactant is
Calcium carbonate
Although both of them are metals and cations, we name Ca2+ "calcium ion" while we name Co2+ "cobalt(II) ion" because___________________
Calcium has fixed charge (2+ only), while cobalt could have variable charge (2+ or 3+).
Give the proper name for this molecule CS2
Carbon disulfide
Name CO properly (Check the recipe in the attachment)
Carbon monoxide
Which is the most abundant and which is the least abundant among the Carbon's isotopes?
Carbon-12 is the most abundant while Carbon 14 is the least abundant
What mean is used to solve the problem of the carbon monoxide byproduct in automobiles?
Catalytic converters
What is the relationship between the periodic table and chemical equations?
Chemical equations represents how the elements in the periodic table interact
What is Chemistry? (there might be multiple answers):
Chemistry is everywhere The human body is a big chemical machine
Which of the following exist as diatomic molecules? (select all correct answers)
Chlorine Oxygen Bromine
What are the sources of ozone depletion? (there might be more than one correct answer)
Cl NO
Neutral solution has a pH of
Close to 7
What is the nuclear symbol for an isotope that has an atomic number of 27 and a mass number of 60?
Co 60 27
Name the following ionic compound Co2Se3
Cobalt (III) selenide
We are able to determine the age of fossils by _________________ (complete)
Comparing the quantities' ratio of decaying Carbon-14 to the stable Carbon-12
The process of going from gas to liquid is called
Condensation
What is the cause of teeth decay? How do toothpastes combat the cause of decay?
Decay of the teeth is caused by the increase in the acidity of the mouth and toothpastes combat it by neutralizing the acidity because toothpastes are base
Given the following ions: Au3+ and S2− What is the name of the ionic compound formed between these two ions?
Gold (III) sulfide
Give the proper name for this molecule As2O3
Diarsenic trioxide
Name P2O3 properly (Check the recipe in the attachment)
Diphosphorous trioxide
Conclusion [include the name of the process and the major product(s)]
Dissolving with Dissociation, resulting in aqueous sodium chloride surrounded by water
Conclusion [include the name of the process and the major product(s)]
Distillation, the outcomes are solid salt and liquid water separated
Which of the following statements are quantitative? (there might be multiple correct answers):
Dozen consists of 12 items The mass of 1 cubic meter of water is 1000 kilogram
How does Albert Einstein's energy (E) and mass (m) equation, E = mc2, relate to fission and fusion ?
During nuclear fission and fusion, there is mass added to the nuclei produced which will be converted to energy following Einstein's equation. double check I have no idea
What mean is used to solve the problem of Particulate matters (PM) produced by power plants?
Electrostatic precipitators
In biology, we see the impact of intermolecular forces in the work of the following biological agents:
Enzymes and proteins
(Syllabus Question) All assessments (not papers) in this course are two attempts with unlimited time, except for the__________ which is one attempt and has a time limit
Exams (midterm and final)
When you increase the volume of a substance, its pH increases too
False
Which of these types of radiation has the greatest ability to penetrate matter?
Gamma rays
How does adding the solute affect the concentration?
The concentration increases
Identify the most significant intermolecular force in water H2O ?
Hydrogen bonding
Which of these formulas represent molecules? (select all correct answers)
I2 H2O
Despite the fact that mercury has stronger intermolecular forces than water, water rises up in a glass tube while mercury moves down. Why?
In addition to the intermolecular force between water molecules, there is attraction force between water molecules and the glass tube. Mercury, on the other hand, is not attracted to the glass tube.
No matter how hard you blow air into the balloon, why can't you inflate a balloon inside a close container?
In order for the balloon to inflate, it has to displace the air around it, which is not possible in a close container
What is the relationship between natural abundance and stability?
In order for the isotope to be abundant in nature, it has to be stable
What is the significance of the periodic table in chemistry?
It has all the elements that make up everything around us
The fact that a substance is solid at room temperature indicates, necessarily, that
It has strong intermolecular forces between its molecules
What is the % abundance of Beryllium-10? Is it stable?
It is unstable, its abundance is around 0%
Among the rocks we eat is Na2CO3. What is its function in food and other? (there might be more than one correct answer)
It is used in laundry (where it is called washing soda) to interact with other ions in water that tend to reduce detergent efficiency. It regulates the acid balance
Write the chemical equation that represents the dissociation of this ionic compound: KOH(s)
K+ (aq) + OH-(aq)
What is the name of this compound? PbO2
Lead (IV) oxide
What are the characteristics of urban areas that increase the possibility of high levels of photochemical smog?
Located in a basin or surrounded by mountains, calm winds, dry weather, sunny, many industries and vehicles
Br2 has London (dispersion) forces between its molecules. It more likely to dissolve in a substance that has ______________ intermolecular forces between its molecules
London (dispersion) forces
Name the following ionic compound MgI2
Magnesium iodide
What is the purpose of the science of Chemistry, in general?
Make models to help us understand and make predictions about our world
How do medicinal drugs work, from organic chemistry point of view?
Medicinal drugs and a disease are like key and lock, and when you have the right chemical (medicine) it will lock into the other chemical (that causes the disease) and interferes with its chemistry.
Which of the following phase changes require "energy absorption"?(There may be more than one correct answer)
Melting Sublimation Vaporization
The product that is formed in the chemical equation { Mg + S à MgS } , is
MgS
(Syllabus Question) What type of documents upload are accepted in this course?
Microsoft Word or pdf only
What happens to the pH value of the 0.25 L chicken soup if you add 0.75L of water to it?
The acidity will decrease when you add 0.75 L of water but it is still acidic
Justify what happens to the concentration while discharging the solution (Explain using the equation of concentration )
The amount of the solute is decreasing and the volume of the solution is decreasing proportionally
Justify what happens to the concentration as you add solute. (Explain using the equation of concentration ) Note: make sure that the concentration probe is immersed in the solution.
The amount of the solute is increasing while the volume of the solution is almost the same
Justify what happens to the concentration while the water is evaporating (Explain using the equation of concentration )
The amount of the solute is the same while the volume of the solution is decreasing
Justify what happens to the concentration as you add water. (Explain using the equation of concentration ) Note: make sure that the concentration probe is immersed in the solution.
The amount of the solute is the same while the volume of the solution is increasing
Justify the reason behind what happened to the concentration after adding solute beyond saturation (Explain using the equation of concentration )
The amount of the solute stays the same in the same volume of solution
What happens to the pH of the blood if you add 0.4L of water to it?
The basicity will decrease when you add water but it is still basic
To depict a three dimensional organic molecule on a piece of paper, we represent the bonds orientation in the following manner:
The bonds that lie on the plain of the paper are represented by regular lines, the bonds pointing forward are represented by wedged solid triangle, and the bonds pointing backward are represented by dashed triangle.
What are the characteristics that identify a chemical formula as an acid?
The compound has H+ ion and dissolved in water.
How does adding the water affect the concentration?
The concentration decreases
Why is it important to flush the water heater tank in your house every year or two?
The high temperature water causes precipitation of limescale that needs to be flushed away
chemistry is the study of
The interactions of matter with other matter and with energy
What do think the major cause behind the clear distinction that sets apart the gas phase from the solid and liquid phases?
The intermolecular forces between the particles in the gas phase is almost zero, while they are significant in the cases of solids and liquids
What is the cause behind the differences between the solid phase and the liquid phase?
The intermolecular forces between the particles of a Solid are stronger than those between the particles of its liquid phase
All of the following statements are major concepts behind the "kinetic theory of gases", with the exception of:
The particles of a gas interact with each other during collisions.
After inflating a balloon placed in a container with a small hole in, you blocked the hole in the container with your finger, as a result, the balloon stays inflated despite the balloon being untied. Furthermore, if you start sucking the air out of the small opening in the container, the untied balloon with start inflating further, rather than deflating, which is the case with all untied balloons.What is causing the balloon to inflate rather than deflate?
The pressure inside the container, and outside the balloon walls, is less than the pressure inside the balloon walls and outside the container. This causes air to move from the high pressure area (outside) toward the balloon in order to reach the low pressure area where you are sucking.
The home made barometer will measure high pressure when_______________
The pressure of the air outside the container is more than inside the container, causing the rubber membrane to flex inward.
What happen to the Pressure when you increase the volume, while keeping the number of particles the same?
The pressure will decrease
What will happen to the Pressure when you decrease the temperature, while keeping the volume and the number of particles the same?
The pressure will decrease
What happen to the Pressure when you increase the temperature, while keeping the volume and the number of particles the same?
The pressure will increase
What will happen to the Pressure when you decrease the volume, while keeping the number of particles the same?
The pressure will increase
What will happen to the Pressure when you increase the number of particles, while keeping the volume the same?
The pressure will increase
To experimentally distinguish between a Colloid and a solution, we use _____________
Tyndall effect
What is special about calcium carbonate (CaCO3) solubility in water?
Unlike most ionic compounds, calcium carbonate solubility in water decreases when the water temperature increases.
Compare the volume of the solid phases of argon, Neon and oxygen to their liquid phases. What do you observe?
The solid phase exhibits constant volume, while the liquid phase exhibits constant volume that is bigger than that of the solid
Compare the motion of the particles that form the solid phases of the argon, Neon and oxygen to their liquid phases. What do you observe?
The solid phase exhibits vibrational motion, while the liquid phase exhibits translational motion
A solution is prepared by combining 10.3 g of Hg(ℓ) and 45.0 g of Ag(s). Identify the solute and solvent.
The solute is Hg(ℓ) while the solvent is Ag(s), because the solvent has more mass than the solute
What do you observe regarding the motion of Neon's particles when you subject each of its three phases to 5-10 seconds of ice (decreasing its temperature)?
The speed of the particles will decrease
What are your observations on the motion of the Neon's particles when you subject its three phases to 5-10 seconds of heat (increasing its temperature)?
The speed of the particles will increase
We call acid-base reactions "neutralization reactions" because
The strength of both will decline significantly, forming close to neutral solution
The difference between amorphous solids and crystalline solids is
Unlike liquids, they are both structurally ordered. Amorphous solids, however, do not have repeating patterns while crystalline solids do.
Evaporation is
The transformation from a liquid to gas at temperatures below the boiling point
Some farmers add lye to the soil because
Their soil is acidic and lye is a base, so by adding lye they bring the soil close to neutral
"All phase changes are isothermal" means
There is no change in the temperature during phases change as all the energy released or gained is directed toward the change in phase.
You encountered several chemists, who claim to be working for the health department, irradiating food products. What does that indicate?
They are killing microorganisms in these food products, consequently extending their shelf life.
Where are the non-metals located in the periodic table?
They are located on the right of the stair case
The modern atomic theory states that: "atoms of one element are the same, while atoms of different elements are different". What cause them to differ?
They differ in their number of protons
How does the pH of 0.25 L of chicken soup differ from 0.5 L chicken soup? Is it acidic or basic?
They have the same pH value, they are acidic
What are your observations on the shape and volume of the gas phases of argon, Neon and oxygen?
They have variable shape and volume (they take the shape and volume of their container)
How are the leaks in underground water pipes located by the use of radioactivity?
They run water that contains radioactive isotopes of hydrogen through the pipes, then they use a Geiger counter to trace any radioactive hydrogen present in the ground around the pipes. If any detected, it would be the location of the leak
A small asteroid crashes to Earth. After chemical analysis, it is found to contain 1 g of technetium-99 to every 3 g of ruthenium-99, its daughter isotope. If the half-life of technetium-99 is 210,000 y, approximately how old is the asteroid?
This indicates that technetium-99 was originally 1+3 = 4 grams, so it went through two half-lives to reach 1 grams. Therefore, it is 420,000 y old.
All substances have intermolecular forces between their molecules
True
Most of the items that we can drink (safely) on the list of this simulation are acidic
True
"Most elements form a singly charged ion. A few elements, however, could form a variable charged ion" Is this statement true or false? what type of elements could form variable charged ions?
True, few metals can form variable charged ions
Which of the following is correct definition of a "solution"?
Two or more substances that are mixed together at the molecular level
smog is produced by_________________ , ____________, _____________and it is exacerbated by __________________
VOCs, NOx, Ozone, temperature inversions
(Syllabus Question) What is the recommended way to contact the instructor?
Via email at [email protected]
As you probably know, a dentist will tell you that soda is bad for your teeth. What other item on the simulation list is the soda's pH closest to?
Vomit
In spite of the fact that sulfur dioxide is twice the mass of water, water is liquid at room temperature, while sulfur dioxide is gas at room temperature. Why?
Water has hydrogen bonding between its molecules, while sulfur dioxide has dispersion forces between its molecules. Hydrogen bonding is far stronger than dispersion forces
How can small insects "walk" on water?
Water has strong intermolecular forces among its molecules due to the hydrogen bonding. Hence its surface tension is high, and high surface tension enables small insects to walk on it.
When acidity increases, the pH value __________ . While when basicity increases, the pH value __________
When acidity increases, the pH value decreases, while when basicity increases, the pH value increases
Why the closed hot barrel was crushed when cooled down?
When the barrel was heated, the kinetic energy of the air particles inside the barrel increased causing increase in the pressure and therefore many of the air molecules left the barrel. When locked and cooled down by the ice bath, the kinetic energy of the air particles inside the barrel decreased, reducing the pressure inside the barrel. Hence the pressure from outside crushed it.
How does radioactivity enable us to know the age of the earth and other fossils/artifacts?
When we analyze samples that exhibit radioactivity, and determine the amount of radioactive element and the amount of its daughter isotopes with high accuracy, we can conclude that a certain fraction of the original radioactive element has decayed. If we know the half-life time of this radioactive element, we can determine the number of half-lives it went through and hence the age of the sample.
Can air freeze? (Note that air is 78% nitrogen, 21% oxygen, and around 0.9% Argon)
Yes, because we can freeze nitrogen, oxygen, and Argon at very low temperature
Is there color change as you add solute to the solution? If yes, describe it.
Yes, the solution's color is getting darker
What happens to the atomic number (Z) and the mass number (A) when a nucleus emits a beta particle (electron)?
Z increases by 1; A is unchanged
What happens to the atomic number (Z) and the mass number (A) when a nucleus emits a gamma ray?
Z is unchanged; A is unchanged
The plant that was used in Socrates's execution is called "Hemlock". It looks like the wild parsnip, celery, and carrot plants. It is poisonous because, in addition to many dangerous chemicals, it contains coniine, which interferes with the signals between neurons causing dizziness and trembling, slows down the heart rate, and eventually can cause paralysis. It can be fatal, because the diaphragm, the muscle that helps control breathing, also becomes paralyzed. The chemical structure of coniine is _________________
a ring of carbon atoms and one nitrogen atom, connected to a chain of carbons.
The following is the general formula of neutralization reaction:
acid + base → water + salt
The most commonly cited products related to health problems are all of the following EXCEPT ______________ products
aftershave
Common sources of volatile organic compounds (VOCs) include:
all of the above
While heating a liquid, the temperature will stop rising at the boiling point of that liquid (Check the heating curve in the last video) because
all the energy is directed toward breaking the intermolecular forces in order to turn the liquid into gas
When a radioactive atom looses two protons and two neutrons, this indicates that it emitted _____________ radiation
alpha
When 3888Sr decays to 3484Kr, a(n) ______________ is emitted
alpha particle
The most effective chemical reaction in launching a rocket is the reaction between ammonium perchlorate and powdered aluminum to yield:
aluminum oxide, water, nitrogen gas, and hydrogen chloride
The single most important factor which determines whether a certain chemical will cause poisoning is the ______________.
amount or dose entered the body
Arrhenius definitions of acid and base are
an acid is any compound that increases the amount of H+ in an aqueous solution. While a base is a compound that increases the amount of OH− in an aqueous solution.
You can prepare a home made acid/base indicator using which of the following household vegetables?
cabbage
The chemical content of a non-prescription drug for relief from acid indigestion and heartburn (such as tums) and considered a calcium supplement is __________________
calcium carbonate
The outcome of the complete combustion of hydrocarbons is ______________
carbon dioxide and water
"Dumbcane", a home plant used widely, is toxic because it contains certain enzymes and calcium oxalate, an acid that's a major component of kidney stones. calcium oxalate and the enzymes could cause all the following EXCEPT ___________
causing hallucinations due to the acid's effect on the chemistry of the nervous system
From the reading, Chemistry is largely about
chemical changes
What determine the identity of an organic compound? (There could be more than one answer)
chemical structure chemical composition
The burning of which fuel is the main source of industrial smog?
coal
What is labelled as "homogenized milk" in the stores is actually type of __________________
colloid
All of the following have nuclear chemistry application except ____________
combustion reactions
All of the following industries are the sources of outdoor Air Pollution EXCEPT _________
companies involved in manufacturing solar panels
Adding pure water to a saturated solution causes the concentration of the solution to ____
decrease
The gas property that enables you to smell an odor of a gas from a long distance is ___________
diffusion
When dispersion forces is the only intermolecular force between a substance' molecules, this substance is usually a gas at room temperature, unless it is a big molecule where it could be a liquid at room temperature. Why?
dispersion forces are the weakest forces. However, when the molecules are big it becomes more effective
A base is called a base because of the amount of hydroxide ions that are dissolved in the solution. Based on this concept, which substance among the list below has most` hydroxide ions dissolved in the solution?
drain cleaner
"Foxglove" is another home plant used widely. It contains a toxic chemical called digitoxin, which - if digested- could cause all the following EXCEPT ___________ .
extreme rash and redness
Currently, we are able to synthesize any organic compound that exists in nature (cost efficiently-) in the lab.
false
There are chemical-free substances in nature, away from industry.
false
Ammonia and bleach are two household cleaners, and mixing them produces _____________
fatal Toxic vapor
The way we should model gas particles in a container, based on the "kinetic theory of gasses", is _____________
few little marbles in a huge football stadium
The process of obtaining energy by splitting a large nucleus is called _______
fission
Which of the following is a solution's property?
homogenous mixture
Which chemical is used as water softener, commonly known as "soda ash" or "washing soda"?
hydrated sodium carbonate
Adding solid solute to an unsaturated solution causes the concentration of the solution to ____
increase
Evaporation acting on an unsaturated solution causes the concentration of the solution to ____
increase
In a complete ionic equation and net ionic equation, the precipitate refers to the
ionic compound that is insoluble in water.
The difference between dissolving ionic compounds and dissolving polar covalent compounds in water is _________________
ionic compounds dissociate into their ions, while polar covalent compounds separate away from each other down to their molecular level.
What mean is used to solve the problem of arsenic contamination in water resulting from household chemicals?
iron chips
Atomic number is the number of ____________(complete)
protons
Mass number is the number of ____________(complete)
protons plus neutrons
A chemical equation describes a chemical
reaction
Before using or mixing any household chemicals, you should _______________
read the warning label on it
adding an indicator to an acid solution changes the color of the acid solution to _______________
red/pink
The following are examples of acute toxicity EXCEPT _____________
repeated exposure to dusts containing quartz can cause scar tissue in the lungs. This effect eventually leads to severe and permanent lung damage.
) _________________ is a plant that looks like bright red berry on a bush, but it contains one of the most poisonous substances in the world. And there's no antidote. The compound in this plant that makes it deadly poisonous is called abrin, and it's different from the other poisons because it's a protein (a ribosome-inactivating protein) so when it gets into a cell, it stops that cell's ribosomes from functioning because it cannot make proteins. Abrin so potent that just one tenth of a milligram can kill an adult.
rosary pea
The primary function of a moderator in a nuclear reactor is to ________
slow down neutrons
The reason the boiling point of sodium chloride is far over 1000 degree Celsius, while the boiling point of water in 100 degree Celsius is
sodium chloride has stronger intermolecular forces between its compounds than water
Silicon dioxide compund exists in all of the following household chemical EXCEPT _______________
solder
Compare the shape of the solid phases of argon, Neon and oxygen to their liquid phases Which phase has constant (fixed) shape?
solid
Adding a solid salt to a saturated solution causes the concentration of the solution to ____
stay the same
Evaporation acting on a saturated solution causes the concentration of the solution to ____
stay the same
(Syllabus Question) What should be included in the subject line of any email or message sent to your instrctor?
the section name which could be online 1, online2, online 3 or blended
All of the following are factors that influence the degree of poisoning caused by a chemical EXCEPT the ______________
time of the day it was used
Which chemical is used in Correction Fluid (liquid paper) such as "wite out"?
titanium oxide
Compare and contrast toxicity and hazard
toxicity is poisoning strength of a chemical, while hazard is likelihood that a chemical will cause poisoning, given its toxicity strength, and the amounts and manner in which it is used, stored and handled
Any chemical can cause poisoning if a sufficient dose of it is taken into the body, including water
true
Mixing household chemicals is _________________
unsafe and could be fatal
Use Table 11.2 "Solubilities of Some Ionic Compounds" (available in the instructions) to decide if a solution containing 0.000092 g of AgCl per 100 g of H2O is unsaturated, saturated, or supersaturated at 25 0 C.
unsaturated
The higher the intermolecular forces between liquid's molecules, the lower its
vapor pressure
The chemical formula C2H4O2 belongs to the household chemical commonly known as ____________
vinegar
Ascorbic acid, C6H8O6 , is the chemical that makes up ___________________
vitamin C
Compare the solid phases of argon, Neon, oxygen, and water. Which one of the four substances forms a hexagonal structure with gaps between the molecules?
water
Capillary action of liquids is related to all of the following phenomena except
water beading up on the surface of waxed cars
The plant that caused milk sickness in the nineteenth century in the American Midwest, where people were dying and nobody really knew the reason (including Abraham Lincoln's mother, Nancy Lincoln, who died in 1818 from drinking milk) was the plant ______________. It turned out that people were dying because their livestock were eating tons of that plant, and the chemical, Tremetol, contained in that plant would end up in an animal's milk, and then people would die from drinking that milk as "secondary poisoning".
white snakeroot
The chemical formula NH3 belongs to the household chemical commonly known as ____________
windex
The arrow in a chemical equation means
yield
