Chem final review
chapter 7
acids & bases
which of the following statements about addition and condensation polymers is true
addition polymers contain all of the atoms of the original monomers, but condensation polymers do not
a compound containing only carbon and hydrogen and which has single bonds and double bonds between atoms is classified as an ____________.
alkene
chemistry and chemicals are involved in _________ part/parts of our lives.
all
which of the following statements is true?
all atoms are not the same different elements cannot have similar atoms. for example, hydrogen, and carbon cannot have similar atoms
which of the following statements is NOT true?
all atoms are unstable all atoms are identical
which of the statements was not a part of dalton's original atomic theory?
all four statements are part of dalton's original atomic theory
amino acids are linked to each other to form proteins by a specific linkage/bond. what is the name of this linkage?
amide
fishes smell bad because there are many compounds with one specific functional group in fishes. identify the functional group:
amine
which of the following statements is/are true?
amorphous polymers tend to be soft and rubbery; in condensation polymerization, small molecules such as water, alcohols, ammonia, or HCl are released as byproducts; rubber band is an elastomer
true
amorphous polymers tend to be very rubbery; crystalline polymers tend to be very rigid; amorphous polymers tend to be soft
theory example
an explanation that has been tested and verified scientists, after many experiments, explain how the temperature of a gas depends on the energy of its molecules.
hypothesis example
an untested explanation a doctor thinks, but has not verified, why a patient has stomach pain
which of the following statements is/are true?
anode is the electrode where oxidation reaction occurs; oxidation and reduction always occur together; hydrogen is used to reduce vegetable oil to make margarines & shortening
which of the statements describes a chemical property?
antacid tablets neutralize stomach acid
organic compounds that contain a benzene ring or possess certain properties similar to those of benzene are called _____ compounds
aromatic
why is the structure of atoms very important?
arrangement of different parts of atom determine various properties of particular atom
j.j. thomson
discovered the atom experimented with the deflection of cathode rays by a magnetic field
quiz 1
chapter 1
quiz 10
chapter 10
quiz 16
chapter 16
quiz 2
chapter 2
quiz 3
chapter 3
exam 2
chapter 3, chapter 4, chapter 5
quiz 5
chapter 5
quiz 6
chapter 6
exam 3
chapter 6, chapter 7, chapter 8
quiz 7
chapter 7
quiz 8
chapter 8
quiz 9
chapter 9
exam 4
chapter 9, chapter 10, chapter 16
dry lab 3
chem 1170
chapter 5
chemical accounting: mass & volume relationships
what holds atoms/ions together in a molecule/ionic crystals?
chemical bonds
chapter 4
chemical bonds: the ties that bond
aluminum reacts with oxygen in the air to produce aluminum oxide Al + Os > Al2O3 what kind of change is this?
chemical change
chapter 1
chemistry: a science for all seasons
secondary structure
coil B pleated sheet A helix; a single helical chain of collagen
which of the following statements about addition and condensation polymers is NOT true
condensation polymers contain all of the atoms of the original monomers, but addition polymers do not both addition polymers and condensation polymers lose some atoms from the original monomers when the polymer is formed both addition polymers and condensation polymers contain all of the atoms of the monomers
which of the methods are the general methods of polymer production
condensation; addition
currently many cell/mobile phone screens use AMOLED display technology. many tv, computer/laptop screens use OLED display technology; what kind of polymers may be used for these display screens?
conductive polymer
wrong
crystalline polymers tend to be semi-liquid
which of the following statements about crystalline and amorphous polymers is correct?
crystalline polymers tend to be stronger, while amorphous polymers tend to have great elasticity
glucose is always composed of 40.0% carbon, 53.5% oxygen and 6.7% hydrogen (by mass). this illustrates the law of -
definite proportions
which of the following statements aren't true?
difference between valence electrons of two atoms can help determine whether a bond is polar or non-polar, noble gases are highly reactive, in covalent bonds, one atom losses electron and other gains electrons
what is chemically correct name of P2O3?
diphosphorus trioxide
dmitri mendeleev
discovered periodic changes in properties of elements when they are listed in order of their atomic weights
what is the name of the compound with the formula CH3CH2CH2CH2CH3
pentane
nylon is a
polyamide
which of the following is the simplest synthetic polymer?
polyethylene
longest to shortest length
1 km 1000 in 10 yards 250 cm
which of the following statements is/are true?
1- butyne and 2- butyne have same chemical/molecular formula; unsaturated hydrocarbon can be converted to saturated hydrocarbon; amide linkage and peptide bonds are name of the same chemical bonds
what is the electron configuration of Cl- anion?
1s^2 2s^2 2p^6 3s^2 3p^6
what is the electron configuration of K+ cation?
1s^2 2s^2 2p^6 3s^2 3p^6
largest mass number to smallest mass number
3 protons, 4 neutrons, 2 electrons; 2 protons, 4 neutrons, 2 electrons; 2 protons, 2 neutrons, 2 electrons; 1 proton, 2 neutrons, 2 electron; 1 proton, 1 neutron, 2 electrons
enter the complementary sequence to the DNA strand: 5'-CGATGACC-3'
3'-GCTACTCGG-5'
how many significant figures will be there in the answer of the following calculations? 6.10 + 5.800
4
how many significant figures does the following number have? 920100.
6
write the element name that corresponds to each element symbol
As: arsenic Co: cobalt I: iodine
formula for barium phosphate
Ba3(PO4)2
determine the number of electrons lost or gained when each atom forms an ion
Be loses 2 electrons. Se gains 2 electrons. I gains 1 electron. P gains 3 electrons.
for each element, identify the charge of its most common ion
Br: -1 Rb: +1 Se: -2 Al: +3
disaccharids example
C12H22O11 sucrose
organic compound examples
C2H6 C4H9NO2S CH3CH2C(=O)H
what is the formula for octane?
C8H18
what is the formula for 2-nonene?
C9H18
which molecule/ion plays a major role in respiratory acidosis or respiratory alkolysis?
CO2
metals:
Ca, Zn, Ag
which substances exhibit only london (dispersion) forces?
Cl2, He
which vitamins are NOT water soluble?
E, K, A
electronegativity from most electronegative to least
F, C, Al, Na, Rb
determine the total number of nonbonding electrons that should be added to each of these molecules.
F-H: 6 nonbonding electrons, H-O-H: 4 nonbonding electrons, O=N-H: 6 nonbonding electrons
margarine is made by reducing carbon to carbon double bonds in vegetable oil. which of the following compound/element/sub-atomic part is used as reducing agent for this purpose?
H2
arranged from most ionic to most covalent
K-F, Ca-F, Br-F, Cl-F, F-F
potassium oxide
K2O
which type of bonds exist in these?
KCl: ionic bonds P4: nonpolar covalent bonds CO: polar covalent bonds BCl3: polar covalent bonds Br2: nonpolar covalent SO2: polar covalent bonds
Li2O: lithium oxide CaS: calcium sulfide
Li charge: +1 O charge: -2 Ca charge: +2 S charge: -2
chemical formula for lithium & fluorine; chemical formula for lithium & selenium
LiF Li2Se
nonmetal:
N, Cl
which of these are ionic compounds?
NH4Cl, KI, BaO
which set of compounds illustrates the law of multiple proportions?
NO, NO2, N2O4
inorganic compounds
Na2S Ca(OH)2 H2O FCl(-F)F
which element/compound is generally responsible for corrosion of most of the metals?
O2
which of the following gas is responsible for acid rain?
SO2
how many valence electrons do atom do each of the elements have?
Sr: 2, Ne: 8, Ga: 3, Bi: 5
which of the following statements is/are NOT true about periodic table of elements?
a (alpha) radiation do not have charge, elements in a given period (in the periodic table) has similar chemical properties, elements in every group (in the periodic table) demonstrate a range of metallic and non-metallic properties
which of the changes are chemical changes?
a candle is burned a silver teapot turns black two clear colorless salt solutions are mixed & a bright orange precipitate forms
law of definite proportions
a compound always contain the same proportion of elements by mass
an organic compound is defined as
a compound containing carbon
law example
a description that predicts what happens, but does not explain how
choose the best definition for the term polymer
a large molecule made of repeating subunits
metals & nonmetals can react with each other to form ions. complete each statement
a potassium atom loses one electron to form a +1 ion. a sulfur atom gains two electrons to form a -2 ion.
choose the best definition for the term monomer
a repeating subunit used to make a polymer
which of the following is/are chemical charges?
a wood block is burning you color your hair using hair color dye iron bench in a park rusted over time
identify the acid in lime/lemon:
abscorbic acid/ citric acid
which of the following statements is/are NOT true?
according to kinetic molecular theory, collisions between gas molecules are not elastic; generally, covalent compounds are soluble in water
vinegar is a solution of _____ in water
acetic acid
classify the characteristics as qualities of either acids or bases
acid: sour flavor, turns litmus paper red, dissolves some metals; base: bitter flavor, turns litmus paper blue, feels slippery
classify the definitions as that of an arrhenius acid, an arrhenius base, or that of a different type of acid or base
arrhenius acid definition: a substance that produces an excess of hydrogen ions (H+) in aqueous solution; arrhenius base definition: a substance that produces an excess of hydroxide ions (OH-) in aqueous solution different definition of acid & base: a substance that can donate a hydrogen ion to another substance, a substance that can accept a hydrogen ion from another substance
which of the following is the smallest portion of an element with the properties of that element?
atom
chapter 3
atomic structure: images of the invisible
what is conserved when one balances a chemical equation
atoms
chapter 2
atoms: are they real?
what is an example of an elastomer?
balloon made from rubber
what is the chemical classification of baking soda?
base
identify one or more parameter for any compound to taste sweet from the following parameters:
basic part, acidic part, right geometry
chapter 16
biochemistry
which of the following is the definition of biochemistry?
biochemistry is the study of chemical reactions and chemicals in all living forms of life.
what parameters determine the properties of a substance?
bonds between atoms in the substance atoms which form the substance
which of the following statements about crystalline and amorphous polymers is NOT correct?
both crystalline and amorphous polymers have great elasticity but have little strength both crystalline and amorphous polymers are strong but have little elasticity crystalline polymers tend to have greater elasticity, while amorphous polymers tend to be stronger
name of BrCl2; name of PCl3
bromine pentachloride; phosphorus trichloride
which of the following statements is/are true?
burning fuel such as gasoline, diesel and coal can cause acid rain; acid turns blue litmus paper to red; water can act as either acid or base
why is it important to understand atomic structure?
by learning about atomic structure, we can find out how atoms combine and form many compounds
of tens of millions known chemical compounds, over 95% are compounds of carbon. why is it?
carbon atoms can form bonds with many different atoms such as H, O, N; carbon is tetravalent, so it forms four bonds; carbon atoms can bond to each other to form long chains and rings
which of the following is NOT a reason for the great variety of organic molecules?
carbon atoms can form more bonds than four bonds
not true
carbon compounds are not vital, life can exist (as it is) without them only 5% compounds out of millions of known compounds are organic compound
true
carbon is unique elements because its atoms can form bonds with one another and form long chains. these chains can have branches and rings. carbon atoms form strong bonds with another carbon atom and nonmetals such as nitrogen, oxygen, and hydrogen atoms. these atoms can be arranged in numerous ways which leads to millions and millions of organic compounds.
which structural feature would enable and organic molecule to serve as a monomer in addition polymerization?
carbon-carbon double bond
valence electrons in each neutral atom
carbon: 4 oxygen: 6 sulfur: 6 nitrogen: 5 chlorine: 7
the -COOH group represents the _________ group.
carboxylic acid
the amino acids in proteins are linked by one specific linkages/functional group. identify the linkage/functional group
carboxylic acid
which two groups of compounds are needed to synthesize esters?
carboxylic acid & alcohol
which of the following functional group/groups is/are present in every amino acids?
carboxylic acid & amine
the process of breaking down molecules to produce energy is known as ________.
catabolism
which of the following statements is/are true?
dispersion forces are present among molecules of nonpolar compound, a solution can be solid, liquid, gas in liquids, particles can move freely around within confined area of the liquid
which of the following statements is/are true?
during a chemical reaction, atoms cannot be destroyed or created a compound always contains the same elements in the definite proportions
dalton's atomic theory
each chemical element is composed of immutable atoms that can combine to form compounds
_______ are polymers will elongate when subjected to a tensile force. they will return to the original shape when the force is removed.
elastomer
chemical bond is related to arrangement of which subatomic particle?
electron
which of the following statements is/are true about the periodic table of elements?
elements in a given group (in the periodic table) have similar chemical properties, y (gemma) radiation does not have mass, most of the elements have metallic properties
which of the following statements is/are NOT true?
enzymes and hormones are same class of compounds; disaccharides cannot be hydrolyzed into simpler carbohydrate compounds
which of the following statements is/are true?
enzymes are polymers; lipids are biological molecules that are insoluble in water but are soluble in nonpolar organic solvents; carbohydrate recieved their name (as carbohydrate) due to their general formula: Cx(H2O)y
which functional group is generally present in fruits and flowers for pleasant fruity and flowery aroma?
ester
a chemist should not take care about account of the matter involved in a chemical change
false
any human can live without polymers
false
every material is not made of atoms
false
materials/chemicals cannot go through any changes
false
polymers cannot be synthesized in a lab
false
scientist have can examined the interior (such as subatomic particles) of an atom directly
false
there are no chemicals in organic food
false
there are only few reaction taking place healthy humans body at any time
false
how do antioxidants protect our cells/ tissues? describe the brief reason we discussed in the class.
free radicals generated in our body, damages cell/tissue via oxidation. consuming junk food/high amount of alcohol/smoking leads to higher amount of free radicals. antioxidants neutralize free radicals and thus protect our cells/body.
atoms or groups of atoms attached to hydrocarbon skeletons give the compounds characteristic chemical and physical properties; such atoms or groups are known as-
functional group
the parts of organic molecules that give compounds characteristic chemical and physical properties are known as _______ ________.
functional groups
if there are no intermolecular forces between atoms/molecules of a matter, then what will be physical state of that matter?
gaseous
chapter 6
gases, liquids, solids, & intermolecular forces
which of the following statements is/are NOT true?
generally, ionic compounds are not electrolyte, ionic compounds are soluble in non polar solvents
monosaccharides example
glucose
polysaccharides
glycogen (C6H10O5)750
reacting with sulfur cross-links the polyisoprene and makes the rubber harder; known as vulcanization.. who invented this?
goodyear
LDPE finds applications as
grocery bags
ernest rutherford
he carried out experiments that measured the scattering of alpha particles by heavy atoms he proposed that most of the mass of the atom is concentrated in a very small, charged nucleus, and that the reset of the atom is largely empty space containing electrons
thermoplastic polymers may be
heated and reformed
quaternary structure
hemoglobin
reduced form of matter is _______ in energy while oxidized form of matter is ______ in energy.
high, low
crystalline polymers are composed of
highly organized polymer chains
niels bohr
his model of the hydrogen atom led to an accurate calculation of the wavelengths of light emitted by an excited hydrogen atom he suggested that electrons travel about the nucleus of an atom in only a few discrete stable orbits
which of the following statements is/are NOT true?
hydrocarbon skeletons in the organic compounds are known as functional groups; saturated and unsaturated compounds are isomers of one another
propane, benzene, acetylene, and 2-butene are all examples of
hydrocarbons
which bond/intermolecular force holds two strands in dna together?
hydrogen bond
classify each substance based on intermolecular forces present in that substance
hydrogen bonding, dipole-dipole, and dispersion: NH3; dipole-dipole & dispersion only: HCl, CO; dispersion only: He
which of the following is/are physical changes?
ice is melted into liquid water liquid water is vaporized water vapor condenses as dew droplets
how does chemistry affect you and the whole society?
in development of new medicine & understanding of how these medicine affects the human body in solving global warming/ climate change understanding of biochemical process in all living bodies development of new products in all aspect of life
which of the following statements is/are true?
in gases, particles are far apart and move freely, melting point and freezing point is the same for a particular substance, according to kinetic molecular theory, temperature is a measure of the average kinetic energy of gas molecules
true
in organic farming, organic means all natural fertilizer/pesticides are used for farming. organic farming has nothing to do with organic compounds.
which of the following statements is/are true about periodic table of elements?
in the periodic table, horizontal rows of elements is known as periods, y (gemma) radiation is more dangerous than a and b radiations, in the periodic table, horizontal rows of elements is known as periods
which of the following statements is/are NOT true about the periodic table of elements?
in the periodic table, vertical column of elements is known as periods, in the periodic table, period (number) does not give any information about electron configuration
which is NOT the best way to deal with plastic pollution?
incineration; toss it to landfill; throw it in the ocean
forces between molecules are known as:
intermolecular forces
which of the following forces determine physical state (solid/liquid/gas) of any matter?
intermolecular forces
group of compounds which have same chemical formula but different structural formula are known as ___________.
isomers
the structures of butane & isobutane are _______ of each other
isomers
natural rubber can be made from the monomer
isoprene
what is "green hydrogen"?
it is when water is split into hydrogen & oxygen, it helps with solar and wind energy
who performed the charge-to-mass ratio of an electron experiment?
j.j. thomson with a beam of a cathode ray
name the body cells/tissue and the organ that produce insulin; why does insulin deficiency lead to diabetes?
langerhans B cells in pancreas produce insulin; insulin converts excess glucose into glycogen (stored in our body and we can use it when we need energy). when there is deficiency of insulin, our body cant get rid of excess glucose; the amount of glucose in our blood increases, which could lead to diabetes
match the terms with their definitions
liquid to gas: boiling, solid to gas: sublimation, solid to liquid: melting, liquid to solid: freezing
glycogen
major storage form of carbohydrates in animals
starch
major storage form of glucose in plants made up of two glucose polysaccharids: amylose and amylopectin
which of the following statements is/are true?
many of mendeleev's predictions were found to be accurate distinct elements have different atoms
elements found to the right of the metalloids on the periodic table display which properties?
many tend to be dull in appearance they tend to form anions they tend to be poor conductors
who was the only person to win two noble prizes in sciences?
marie curie
false (weight & mass)
mass & weight are the same thing your weight on the moon is the same as your weight on the earth
law of conservation of mass
matter is neither created nor destroyed in a reaction
which best describes what happens when molecular compounds go through sublimation process?
molecules arranged in a regular pattern change to an irregular pattern
which best describes what happens when molecular compounds melt?
molecules arranged in a regular pattern change to an irregular pattern
which best describes what happens when molecular compounds freeze?
molecules arranged in an irregular pattern change to a regular pattern
in 1911, hans geiger and ernest marsden, working under ernest rutherford, conducted an involving alpha particles and gold foil that led to the discovery of the nucleus in atoms the nucleus of an atom accounts for
most of the atom's mass but very little of its size
match power of ten to the prefixes
nano: 10^-9 centi: 10^-2 milli: 10^-3 kilo: 10^3 micro: 10^-6 mega: 10^6
which of the following is/are true?
nonmetal atoms generally gain electrons to become anions, generally, Al atom loses 3 electrons to become Al^3+ ion. (Al belong to Group 3A)
cellulose
not digestible by humans
natural polymers which carry the coded genetic information that makes each individual unique are:
nucleic acids
DNA and RNA are polymers. what is the name of their monomer unit?
nucleotide
false
objects made from thermosetplastic can be remolded again and again in different shape.
true
objects made from thermosetplastic cannot be remolded again and again in different shape. objects made from thermoplastic can be remolded again and again in different shape. thermoplastic polymer can be soften when heated and thermoset plastic cannot be soften when heated.
which color/colors neon can be made to glow?
orange-red
primary structure
order of amino acids; Gly-Ala-Val-Leu
what is the definition of organic chemistry?
organic chemistry is the chemistry of carbon containing compounds
chapter 9
organic chemistry; carbon compounds
tertiary structure
overall shape of a single polypeptide unit; a single hemoglobin subunit with heme
chapter 8
oxidation & reduction: burn & unburn
which element is needed for burning to take place?
oxygen
what is the chemical nature?
pH= 6.5- slightly acidic; pH= 13- highly basic
how many levels chemical phenomena can be represented?
particle (ionic/aromic/molecular) level, symbolic & mathematical level, macro (large scale) level
true
polymers are in every cell of human body polymers are made of monomers polymers are everywhere around us
false
polymers are micro-molecules
chapter 10
polymers; giants among molecules
what essential parts are needed to make a battery?
porous barrier or salt bridge, reducing agent, oxidizing agent
amino acids are the "building blocks" of
proteins
most enzymes are-
proteins
what is another name of hydrogen ion?
proton
why is quantitative aspect of chemistry very important?
quantitative aspects of chemistry can provide lot of information about properties if the matter
which atomic model is currently accepted as true representation of an atom?
quantum model
an electric eel generates 600 volts of shock with a ______ reaction occuring in its body
redox
combination of oxidation and reduction reaction is called a _____ reaction
redox
corrosion of metal mostly involves a _______ reaction
redox
which of the following statements is/are NOT true?
reducing agent themselves get reduced during redox reaction; human body gets energy by reducing glucose in the cells
who did the experiment with the charge of an electron demonstrated?
robert millikan
what is the taste of the compounds which are formed when acid reacts with base?
salty
hw 1
sapling
hw 10
sapling
hw 16
sapling
hw 2
sapling
hw 3
sapling
hw 4
sapling
hw 6
sapling
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sapling
hw 8
sapling
hw 9
sapling
solid fats (such as lards) have a high proportion of _______. such compounds are generally considered unhealthy.
saturated fatty acids
which technique is used to generate image of individual atoms?
scanning tunneling microscopy
a scientist provides his logical opinion (which is not verified/tested yet) to explain certain phenomena. this scientist's opinion is an example of:
scientific hypothesis
______, _______, and _______ of molecules dictate how molecules interact with one another.
shape, size & polarity
exam 1
sig figs, chapter 1, chapter 2
symbol for each elements
silver: Ag calcium: Ca neon: Ne
monomers are
small building blocks of polymers
density of gas phase < density of liquid phase = density of solid phase
solid has fixed shape & volume, liquid has variable shape & fixed volume, gas has variable shape & variable volume
classify the substances by whether they are soluble or insoluble in water
soluble in water: SO2 (a polar gas), C3H7OH (a polar liquid), NaCl (table salt, an ionic solid); insoluble (or very low solubility) in water: C6H14 (a nonpolar liquid), C (graphite, a nonpolar solid), CH4 (a nonpolar gas)
scientific method order
start: observation of physical world create hypothesis about observation test consequences of hypothesis report outcome: finish
what does the word stoichiometry mean?
stoichiometry means measurement of elements
classify the compounds as strong acids or weak acids
strong acid: HNO3, HBr, H2SO4; weak acid: H2CO3, HF
in the context with small molecules with similar molar masses, arrange the intermolecular forces by strength
strongest: hydrogen bonding, dipole-dipole interactions, london dispersion forces: weakest
compound name of SrF2 and SrS
strontium fluoride; strontium sulfide
what is the primary element used in the vulcanization of rubber?
sulfur
natural rubber is soft and tacky when hot. natural rubber can be cross linked with a __________ element to make it harder. this process is known as ________. __________ invented this process.
sulfur; vulcanization; Charles Goodyear
which event did change the definition of organic chemicals?
synthesis of urea (an organic compound) from ammonium cyanide (an inorganic compound)
which of the following are characteristics of science?
tentative, predictive, reproducible
carbon is almost always
tetravalent
which of the following is a reason for the great variety of organic molecules?
the ability of carbon to form chains isomerism carbon forms bonds with a variety of elements, including, H, O, N, Cl and Br
which observation illustrates law of definite proportions (law of constant composition)?
the c:o mass ratio of a particular compound is the same, regardless of the size or source of the sample burning 10g of propane produces twice as much carbon dioxide as burning 5g of propane
which observation illustrates law of multiple proportions?
the c:o mass ratio of one compound is exactly double that of another compound
what is the chemical nature of a soda drink with the pH of 2.5; why does it have this chemical nature?
the chemical nature is acidic; when soda is manufactured they put CO2 in water under pressure, where the CO2 reacts with water to form carbonic acid making soda acidic.
what is the chemical nature of this soda drink? why do they have this chemical nature?
the chemical nature of most of the soda drinks is acidic; when soda drinks are manufactured put CO2 in water under pressure. this CO2 reacts with water under pressure and forms carbonic acid. due to this carbonic acid, soda drinks are acidic.
a copper block sink to the bottom of water tank. this shows that
the density of water is less than the density of copper block
which discovery is the reason why dalton's assumption that all atoms of the same element have the same mass and other properties is no longer valid?
the discovery of isotopes
one of the advantages of incinerating plastics is
the high fuel value
which of the statements are consistent with the law of constant composition (definite proportions)?
the mass percentage of calcium plus the mass percentage of sulfur in every sample of calcium every sample of calcium sulfide will have 55.6% mass of calcium the mass ratio of S to Ca in every sample of calcium sulfide is 0.80.
which definition best describes the term molar mass?
the mass, in grams, of one mole of a substance
how or why was neutron discovered?
the nucleus has two protons so, its mass should be double of hydrogen's mass. the mass of He is four times mass of H. neutron was discovered to solve this puzzle.
which is a postulate of the kinetic molecular theory of gases?
the particles that compose a gas are so small compared to the distances between them that the volume of the individual particles can be assumed to be negligible
which statement is a postulate of the kinetic molecular theory of gases?
the pressure exerted by the gas is due to the gas particles colliding with the container walls
for a fixed amount of gas at a fixed temperature, what will happen if the volume is doubled?
the pressure exerted by the gas will halve
what effect do valence electrons have on the reactivity of elements?
the reaction of an element with another element is dictated by the number of electrons in each of their outermost shells.
which of the following parameter are determined by chemical bonds?
the strength of any substance 3-d shapes of molecules structural integrity of body organs the state (solid/liquid/gas) of a substance at given temp.
which of the following statements is/are NOT true?
the taste of the compounds which are formed when acid reacts with base is sweet; arrhenius acid-base theory can explain basicity of ammonia
false
the term "organic" has same meaning in the field of organic chemistry and organic farming/food in organic farming, only organic compounds are used organic farming is used to synthesize organic compounds
which of the following statements is/are NOT true?
thermosetting plastic polymers can be reheated and molded in new shapes again and again; you cannot eat ant polymer
why is diamond different from graphite/soot (even though they are all made from the same element)?
these substances are different because the atoms are bonded in different ways in these substances
which statement relating monomers and polymers is correct?
they have the different chemical and physical properties
which statements relating monomers and polymers is NOT correct
they have the same chemical and physical properties the monomer is usually a solid, while the polymer is usually a liquid or gas they have the same chemical formula
why wont balsamic vinegar and olive oil mix?
they won't mix since balsamic vinegar is polar and olive oil is non polar; for two liquid of substance to get mixed & create a solution, the rule of thumb "like dissolves life," since balsamic vinegar & olive oil have different polarity characteristics, they will not mix
how do scientists gather information about different parts (interior parts) of the atoms?
through cleverly designed experiments, interpreting the indirect evidences and using the power of deduction
why do people use antacids?
to get rid of too much acid in the stomach
what is NOT an example of elastomer?
toy made from regular wood a chair made of HDPE a pen made from metal
alkyne have which of the following bond in its structure?
triple bond
atoms determine how matters behave
true
life can be defined with help of chemistry
true
oxidation reaction always occur in conjunction with reduction reaction
true
there are many acid-base reactions taking place in the healthy human body
true
there are many polymer molecules in your body
true
there are polymers in your food
true
we should recycle polymers because source (of many polymers) is in limited supply.
true
your body can manufacture some of the specific compounds it needs to stay healthy
true
the first organic compound to be synthesized in a chemists laboratory was
urea
which is the best way to deal with plastic pollution?
use as little plastic as you can and recycle it
why valence electrons are very important in chemistry?
valence electron are the only electron that take place in any chemical reaction
why can we consume vitamin c in excess but not vitamin d in our food or supplements?
vitamin c is water soluble, so our body may get rid of its excess via urination or other similar mechanism; vitamin d is not water soluble, so our body cannot get rid of its excess causing its build up in the body leading to disease
________ is the most common liquid on earth.
water (H2O)
which observation illustrates the law of conservation of mass?
when 3g of carbon reacts with 8g of oxygen, 11g of carbon dioxide is produced
which of the following natural pesticide produced by mexican marigold?
xanthophyll
true (weight & mass)
your mass on the moon is the same as your mass on the earth
