chemistry final exam- allsteadt
When the equation Fe2O3 + H2 > Fe + H2O is balanced using whole number coefficients, what is the coefficient of H2?
3
Which phrase best describes an apple? A.heterogeneous mixture B.homogenous compound C.heterogeneous substance D.homogenous mixture
A
Which of these statements characterize the nucleus of every atom?
It has a positive charge and it is very dense
Which if these folowing series is ordered from smallest to largest? A. Ug, cg, mg, kg B.mm, dm, m, km C. Us, ns, cs, s D. nL, mL, dL, cL
B
Which pair of orbitals has the same shape? A.2s and 2p B.2s and 3s C.3p and 3d D.more than one is correct
B
Whixh awnser represents the measurement 0.00428 g rounded to two significant figures? A.4.28 x 10^3 g B.4.3 x 10^-3 g C.4.3 x 10^3 g D.4.0 x 10^-3 g
B
Which element is likely to form an ionic conpound with chlorine? A.iodine B.cesium C.helium
B. Cesium
A hypothesis may be rejected after an experiment because experiments are used to test hypotheses
true and true An experiments are used to test a hypotheses is just made by observing the information given, you shouldn't just get rid of you hypothesis you should figure for why is was disproved.
unshared pair
A pair of valence electrons that is not shared between atoms
Which element is paired with the wrong symbol? A.sulfer,S B.Potassium, P C.Nitrogen,N D.calcium, ca
B
All of the nonmetals for which the atomic number is a multiple of five
b,Ne,P,At
A.gains two electrons B.loses two electrons C. Gains three electrons D. Loses one electron E. Gains one electron 1. Iodine 2. Magnesium 3. Cesium 4. Phosphorus
1.E 2.B 3.D 4.C
7*Explain why the arrangement of electron pairs is tetrahedral in each molecule. (Page 251)
(C, N, S, and F) have the sum of bonding and non-bonding pairs of 4.
What is the formula of ammonium carbonate?
(NH4)2CO3
10* Write a balanced equation for the reaction.Include states for reactants and product. (When Ammonium carbonate is heated ,water, ammonia, and carbon dioxide are produced. ) (Page 351)
(NH4)2CO3--->2NH3+CO2+H2O
Classify the following (A)compound (B)heterogeneous mixture (C)element (D)homogenous mixture -air -carbon monoxide -zinc -mushroom pizza
-D -A -C -B
The volume of the liquid in the graduated cylinder is reported as 31.8 mL. how many significant figures?
3, they are all nonzero digits
an over-the-counter medicine has 325 mg of its active ingredient per tablet how many grams does this mass represent
0.325g
How many orbitals are in the following sublevels A. 4s sublevel
1
the radioisotope radon-222 has a half-life of 3.8 days. How much of an initial 20.0g sample of radon-222 would remain after 15.2 days \?
1.25g
A silver bar has a mass of 368 g. What is the volume in cm^3 of the bar? The density of silver is 19.5 g/cm^3
18.9 cm^3
Select the correct electron configuration for silicon, atomic number 14.
1s2/2s2/2p6/3s2/3p2
The electron configuration for an element in the halogen group should always end with...
1s² 2s² 2p⁵
Electron configuration for silicon.
1s²2s²2p⁶3s²3p²
how many meters does a car moving at 95km/h tavel in 1/0
26m
Which pair of orbitals has the same shape?
2s and 3s
Which pair of orbitals have the same shape?
2s and 3s
How many valence electrons are in a molecule of phosphoric acid, H3PO4?
32
which electron transition results in the emission of energy
3p to 3s
47.70
4
Ge
4 energy levels: Si, Ge, Sn
P2+O2---> P3Q (Page 383) 4) write a balanced equation 5) identify the limiting reageant
4)3P2+Q2--->2P3Q 5)P2
Which answer represents the measurement 0.00428 g rounded to two significant figures?
4.3 * 10³g
which answer represents the measurement 0.00428 g rounded to two significant figures
4.3 x 10-3g
How many nitrogen-14 atoms (¹⁴N) would you need to place on the right pan to balance three calcium-42 (⁴²Ca) on the left pan of the "atomic balance" below? Describe your method you used to determine your answer, including any calculations.
42/14=3 3*3=9 9 nitrogen-14 atoms
How many neutrons does the atom of thia isotope contain? 84/36 Kr
48n
How many valence electrons does a arsenic have
5
Which one of these statements characterize the nucleus of every atom? I. It has a positive charge II.It is very dense III.It is composed of protons, electrons, and neutrons A. I and II B. II and III C. I and III D.I, II, and III
A
Se
6 valence electrons: As, Se, Br
A graduated cylinder contains 44.2 milliliters of water. a 48.6-g piece of metal is carefully dropped into the cylinder. when the middle is completely covered with water the water rises to the 51.3 milliliter mark. what is the density of the metal?
6.8 g/mL
How many valence electrons does argon have?
8
How many valence electrons does arsenic have?
A
Which of the following is not a chemical change? A.paper being shredded B.steel rusting C.charcoal burning D.newspaper yellowing in sun
A
Which of these are essencial parts of daltons aromic model? A.indivisable atoms B.electrons C.atomic nuclei D.neutrons
A
Which of these descriptions is incorrect? A.proton:positive charge, in nucleus, mass of 1 amu B.electron:negative charge, mass of 0 amu C.neutron:mass of 1 amu, no charge
A
Which of these statements does not describe every binary molecular compound? A.molecules of binary molecular compounds are composed of two atoms B.the names of binary molecular compounds contain prefixes C.the names of binary molecular compounds end in the suffix ide D.binary molecular compounds are composed of two nonmetals
A
Which substance contains both covalent and ionic bonds? A.NH4NO3 B.CH3OCH3 C.LiF D.CaCl2
A
Explain the difference between an orbit in the Bohr model and an orbital in the quantum model of the atom.
A Bohr model has order and the quantum model is an electron cloud.
What is the outer shell configurations for: A. Sulfer B. Germanium C. Beryllium
A. S^2 p^4 B. S^2 p^2 C. S^2
Identify the larger atom of each pair A.calcium and barium B.silicon and sulfer
A.barium B.silicon
Classify each of the following as homogenous or heterogeneous A.page of this textbook B.banana split C.water in bottled water
A.hetero B.hetero C.homo
Identify each as a chemical or physical change A.melting of iron B.lighting a match B.grinding corn C.souring of milk
A.physical B.chemical C.physical D.chemical
Whats the name of AlCl3?
Aluminum chloride
Describe how Rutheford's gold foil experiment disproved Thomason's plum pudding model of the atom.
An apha ray was shot at a piece of gold foil. Most of the particles went through but some where deflected. Discovering the atom is mostly empty space. Disproving Thomson model that has to unify between the different particles
Se
An atom of which element has the greatest attraction for electrons in a chemical bond?
with which of the following statements would john Dalton have agreed in the early 1800s
Atoms are the smallest particles of matter, the mass of an iron atom is different from the mass of copper atom, every atom of silver is identical to every other atom of silver, a compound is composed of atoms of two or more different elements.
Thallium has two isotopes, thallium-203 and thallium-205. Thallium's atomic number is 81 and its atomic mass is 204.38 amu.
Atoms of both isotopes have 81 protons.
Aufbau principle, the pauli exclusion principle, and the hund's rule.
Aufbau principle electron go in from lowest orbital. Pauli exclusion principle can hold 1 to 2 electrons. Hund's rule al up arrows are drawn in first.
Select the correct electron configuration for silicon, atomic number 14. A. 1s^2 2s^2 2p^2 3s^2 3p^2 3d^2 4s^2 B. 1s^2 2s^2 2p^6 3s^2 3p^2
B
Thallium has two isotopes, thallium-203 and thallium-205. Thallis atomic number is 81 and its atomic mass is 204.38 amu. Which statement about the thallium isotopes is true? A.there is more thallium-203 in nature B.atoms of both isotopes have 81 electrons C.thallium-205 atoms have fewer nuetrons D.the most common atom of thallium has a mass of 204.38 amu
B
The electron configuration for an element in the halogen group should always end with A. ns^2 np^6 B. ns^2 np^5 C. ns^2 np^4 D. ns^2 np^2
B
In a ______________ each side of the equation has the same number of atoms of each element
Balanced equation
Which statements are correct when barium and oxygen react to form an ionic compound.
Barium atoms lose 2 electrons and from a cation. Oxygen atoms from oxide anions, in the compound the ions present ina one to one ratio.
A metal in group 5A
Bi
A bond in which two atoms shate a pair of electrons is not A.a coordinate covalent bond B.a polar covalent bond C.an ionic bond D.a nonpolar covalent bond
C
A nonmetal in group 4A
C
An atom composed of 16 protons 16 electrons and 16 neutrons is A.48/16 S B.16/32Ge C.32/16S D.16/32S
C
As the wavelength of light increases, A. The frequency increases B.the speed of light increases C.the energy decreases D.the intensity increases
C
For which compound name is the incorrect formula given? A. Magnesium iodide MgI2 B. Potassium selenide K2Se C. Calsium oxide Ca2O2 D. Aluminum sulfide Al2S3
C
Which electron confoguration represents a nitride ion? A. 1s2 2s2 3s2 4s2 B. 1s2 2s2 2p3 C. 1s2 2s2 2p6 D. 1s2
C
Which of these bonds is most polar? A.H-Cl B.H-Br C.H-F D.H-I
C
Which of these is not an ionic compound? A. KF B. NaSO4 C. SiO2 D. Na2O
C
In the third energy level
a maximum of 18 electrons are allowed
Ca2+ or Mg2+
Ca2+
Explain at least two ways that chemistry contributes to agriculture.
Chemistry contributes to agriculture, with jelly fish glowing potatoes, also pinworn pesticide.
Explain at least two ways that chemistry contributes to the field of medicine
Chemistry contributes to medicine field with safe reliable medicine, plastic skin.
And atom of an element has 17 electrons. give the name and symbol of the element and write the conplete electron configuration
Cl: 1s^2 2s^2 2p^6 3s^2 3p^5
photograph
Clues a chemical change is happening the transfer of energy, like precipation on the glass, color change or temperature change.
A _____________ is a chemical change in which two or more substances react to form a single new substance
Combination reaction
A _______________ is a chemical change in which two or more substances react to form a single new substance
Combination reaction
A _______________ is a chemical change in which an element or compound reacts with oxygen
Combustion reaction
A ________________ is an equation that shows dissolved ionic compounds as dissociated free ions
Complete ionic equation
What do we call a problem that does not require any calculations, but instead requires us to apply a concept to a new situation?
Conceptual problems
H2O
Covalent
H2S
Covalent
Cu+ or Cu2+
Cu+
Copper, silver, and gold are all excellent conductors of electricity. From this information, what can you conclude about elements that share the same column of the period table?
Cu, Ag, Au all have the same valence electrons.
An over the counter medicine has 325 mg of its active ingredient per tablet. How many grams does this mass represent? A.335,000g B.32.5g C.3.25g D.0.325g
D
If a substance contracts when it freezes, its: A.density will remain the same B.density will increase C.density will decrease D.change in density cant be predicted
D
In the third energy level, A.there are two energy sublevels B.the f orbital has 7 orbitals C.there are three s orbitals D. A maximum of 18 electrons are allowed
D
When a bromine atom gains an electron: A. A bromide ion is formed B. The ion formed has a 1- charge C. The ion formed is an anion D. All the above are correct
D
8*When Ammonium carbonate is heated ,water, ammonia, and carbon dioxide are produced. WHat type of chemical reaction is occuring? (Page 351)
Decomposition reaction
A _______________ is a chemical change in which a single compound breaks down into two or more simpler products
Decomposition reaction
Skeleton equation
Does not indicate amount of reactants and products
A ________________ is a chemical change involving an exchange of positive ions between two compounds
Double replacement
Which of these descriptions is incorrect?
Electron:negative charge in nucleus, mass of 0 amu
Decide whether each statement is true or false. THEN decide whether the second statement is the correct statement for the first statement. 10*A mole ratio is always written with the large number in the numerator BECAUSE A mole ratio will always be greater than one.
FALSE,FALSE,NO
Decide whether each statement is true or false. THEN decide whether the second statement is the correct statement for the first statement. 9* The coefficients in a balanced equation represent the relative masses of the reactants and products BECAUSE The mass of the reactants must equal the mass of the products in a chemical reaction.
FALSE,FALSE,NO
The element hydrogen is a metal Because Hydrogen is on the left in the periodic table
False amd false
There are five significant figures in the measurement 0.00450m because all zeros to the right of the decimal point in a measurement are significant.
False and False because the zero s are leafing zeros, leading zeros are not counted. There would only be 3 sig figs
Precise measurements will always be accurate measurements because a value that is measure 10 times in a row must be accurate
False and False precise measurements can be accurate but not all the time. A true value is an accurate measurement, a precise measurement doesn't have to be a true value, but are equal to the founded info.
Among all the elements in a period, the noble gas always has the smallest ionization energy Because Within any period, atomic radii tend to decrease moving from right to left
False and false
Electronegativity values are higher for metals than for nonmetals Because Atoms of nonmetals are among the largest atoms True or false
False and false
fingernail-polish remover (mostly acetone) is a liquid at room temperature. would you describe acetone in the gaseous state as a gas or vapor?
Fingernail-polish remover would be a gas, because a vapor is usually gaseous when a liquid and solid at room temperature.
Fusion reactions produce enormous amounts of energy.
Fusion is not used to generate electrical power because of the high temperature needed. and once the reaction has started it can't be stopped.
9*Write formulas for the reaction products. (When Ammonium carbonate is heated ,water, ammonia, and carbon dioxide are produced. ) ? (Page 351)
H2O,NH3,CO2
(insert picture of table) 6. Draw the electron dot structure for each example molecule. (Page 251)
HHCHH, CLNCLCL, HHSHH, HF
12.1 g magnesium and 7.9 g oxygen
How many grams of magnesium and oxygen react to form 20.0 grams of magnesium oxide?
Which of the following properties increases as you move across a period from left to right? I. Electronegativity II.Ionization energy III. Atomic radius
I and II
Based on what you have leaned in this unit, do you think that nuclear power is a worthwhile investment.
I don't think a nuclear power isn't a worthwhile investment. There is a wast of fuel rod. These fuel rods have to be put in a pool of water of decades before there not radioactive. Even then there still can be radioactive. Some reaction can happen and then can't be stop, cause disasters. Which make these places radioactive for years. Nuclear power comes with great risks.
Do you think there are new elements left to discover? Why or why not? If so, what is the lowest atomic number a new element could have?
I think there is new elements left to be discovered. The smallest element is 113 and there can't be two elements with the same atomic number.
Which statements are correct when barium and oxygen react to form an ionic compound? I. Barium atoms lose 2 elements and form a cation II. Oxygen atoms form oxide anions (O2-) III. In the compound the ions are present in a one-to-one ratio.
I, II, III
Which of the following statements about the periodic table are correct? I. Elements are arranged in order of increasing atomic mass II. A period is a horizontal row III. The properties of the elements within a period vary from element to element
I,II,III
Which of these statements about the periodic table is correct? I. Elements are arranged in order of increasing atomic mass II. A period is a horizontal row III. nonmetals are located on the right side of the table
II and III
use the arrangement of particles in solids and gases to explain why solids are not as easy to compress as gases
In a solid the particles are closely compact and aren't moving as much. when in a gases the particles are freely moving and can be directed compressed easier.
A student is planning a science fair project called "Does Temperature Affect How HIgh a Basketball can Bounce?
Independent Temperature Dependent How high the basketball is bounced Constant Environment, air pressure, basketball brand
MgCl2
Ionic
Na2S
Ionic
Which of these statements characterize the nucleus of every atom?
It has a positive charge, and it is very dense.
Spectator ion
Not directly involved in a chemical reaction
lissa, lamont, leigh ann
Lissa weight are neither accurate or precise. Lamont weights are accurate and precise Leigh Ann wrights are not accurate but are precise
Activity series
List of elements in decreasing reactivity
4.3 g
Magnesium metal burns vigorously in oxygen to produce the compound magnesium dioxide. Use the law of conservation of mass to identify the mass labeled (a).
22.6 g
Magnesium metal burns vigorously in oxygen to produce the compound magnesium dioxide. Use the law of conservation of mass to identify the mass labeled (b).
19.0 g
Magnesium metal burns vigorously in oxygen to produce the compound magnesium dioxide. Use the law of conservation of mass to identify the mass labeled (c).
Where are metalloids found and why were they given this name?
Metalloids are found on the stair case because there share properties of metals and nonmetals.
What are three characteristics of metals?
Metals are positive, great heat conductors, and are also maluable
The ________________ is an equation for a reaction in solution that shows only those particles that are directly involved in the chemical change
Net ionic equation
What are three characteristics of nonmetals?
Nonmetals are negative, not heat conductors, also brittle.
Why do nonmetals tend to form anions when they react to form compounds
Nonmetals tend to form anions because the want more electrons
describe the process of nuclear fission as a nuclear chain reaction. why are neutron moderation and neutron absorption necessary in nuclear power plant.
Nuclear fission is when neutron are thrown at an element causing it to split. Neutron moderation slows down the neutrons. Neutron absorption, take away neutrons.
Coefficients
Numbers in front of formulas
Which list contains elements that fall within the same group on the periodic table?
O, F, Ne
Lavoisier helped to transform chemistry from a science of _____ to a science of _____
Observation, measurement
Decomposition reaction
One compound breaks down into two or more products
Single replacement reaction
One element replaces another in a compound
Cl
Out of the elements: O, Cl, F; which one has the largest electronegativity?
F
Out of the elements: O, Cl, F; which one has the smallest radii?
CI- or P3-
P3-
10* Which choice describes what happens as each of the following elements forms its ion? (Page 211) phosphorus
Phosphorus is located in Group 5A and has five valence electrons. Therefore, three electrons must be added to phosphorus in order to obtain an electron configuration of a noble gas
By using the general rules for solubility of ionic compounds, you can predict the formation of a
Precipitate
Pure chemistry and applied chemistry?
Pure chemistry is for knowledge, when applies chemistry has a purpose.
Combustion reaction
Reacts with oxygen
Chemical equation
Representation of a chemical reaction
What are the two things that chemists analyze to discover that make-up of matter in the universe?
Rock samples and light
Which of the following substance is not an ionic compound
SiO2
A _________________ is a chemical change in which one element replaces a second element in a compound
Single replacement reaction
A ________________ is a chemical equation that does not indicate the relative amounts of the reactants and products
Skeleton equation
And Ion that appears on both sides of an equation and is not directly involved in the reaction is called a
Spectator ion
catalyst
Speeds up a reaction
An atom composed of 16 protons, 16 electrons, and 16 neutrons is
Sulfur-32
Decide whether each statement is true or false. THEN decide whether the second statement is the correct statement for the first statement. (Page 383) 6* Even stoichiometry calculation uses a balanced equation. BECAUSE Every chemical reaction obeys the law of conversation of mass.
TRUE,TRUE,
Decide whether each statement is true or false. THEN decide whether the second statement is the correct statement for the first statement. 8* The amount of the limiting reagent left after a reaction is zero BECAUSE the limiting reagent is completely used up in a reaction.
TRUE,TRUE, YES
Decide whether each statement is true or false. THEN decide whether the second statement is the correct statement for the first statement. (Page 383) 7* A percent yield is always greater than %0 and less than 100% BECAUSE the actual yield in the reaction is never more than the theoretical yield.
TRUE,TRUE,NO
What families are included in the s block?
The Alkaline metals and the alkaline earth metals are included in the s block.
dipole
a molecule that has two poles called a dipolar molecule or
combination reaction
a chemical change in which two or more substances form a single new substance.
And 1 kilogram still bar is brought to the moon. How are its masses and its weight each affected by this change in location?
The mass of the steel bar remains the same the weight of the bar changes because the gravitational forces on the moon is different than it is on earth
window b
The species in window A reacts. Use the law of conservation of mass to determine which window best represents the reaction products.
As the wavelength of light increases
The wavelength and frequency of light are inversely proportionate to each other. The frequency decreases
Explain what is wrong with the statement, "Theories are proven by experiments."
Theories aren't just proven by experiments theories are made with lots of observations and many different experiments.
Identify the spectator ion in this reaction. [ BaOH)2(aq) + H2SO4(aq) > BaSO4(s) + H2O(1) ]
There is no spectator ion
which of the following is not a chemical change
a paper being shredded
A calcium atom is larger than a calcium ion Because Ions are always larger than the atoms from which they are formed True or false
True and false
Combination reaction
Two substances form one new compound
13.3 g
Using either you graph or math/algebra, determine how many grams of magnesium oxide formed when 8.0 g of magnesium is burned?
compound
Which description correctly identifies carbon monoxide?
silicon
Which of the following is the most reactive metal? neon, aluminum, beryllium, lithium, silicon
double- replacement reaction
a chemical change involving an exchange of positive ions between two compounds.
skeleton equation
a chemical equation that does not indicate the relative amounts of the reactants and products.
how must the electronegativities of two atoms compare if a covalent bond between them is to be polar.
You must subtract the electronegatvities to see if the value is between 1 and 2 to figure out the strong polar covalent bond.
decomposition reaction
a chemical change in which a single compound breaks down into two or more simpler products.
combustion reaction
a chemical change in which an element or compound reacts with oxygen, often producing energy in the form of heat and light.
single-replacement reaction
a chemical change in which one element replaces a second element in a compound.
which type of chemistry might study how an athlete uses energy during a competition.
a physical chemist might study how an athletes uses energy, because they study the transfer of energy as matter undergoes change.
chemical equation
a quick, short-hand notation to convey as much information as possible about what happens in a chemical reaction.
catalyst
a substance that speeds up the reaction but is not used up in the reaction
52*Balance each equation and determine its type. (Page 347) a) Hf+N2--->Hf3N4 b) Mg+H2SO4--->MgSO4+ H2 c)C2H6+O2--->Co2+H2O d)Pb(NO3)2+NaI--->PbI2 + NaNO3 e) Fe+O2--->Fe3O4
a) 3Hf+ 2N2--->Hf3N4 COMBINATON b) Mg+H2SO4--->MgSO4+H2 SINGLE REPLACEMENT c) 2C2H6+7O2--->4CO2+6H2O COMBUSTION d) Pb(NO3)2+2NaI--->PbI2+2NaNO3 DOUBLE e) 3Fe+2O2--->Fe3O4 COMBINATION
48* Use the activity series of metals to write a balanced chemical equation for each single replacement reaction: (Page 347) a) Au (s) + KNO3 (aq) ---> b) Zn (s) + AgNO3 (aq) ---> c)AL(s) + H2SO4 (aq) --->
a) Au (s) + KNO3 (aq) ---> Au(NO3)+K b) Zn (s) + 2AgNO3 (aq) ---> Zn(NO3)2+2Ag c)2AL(s) + 3H2SO4 (aq) ---> Al2(SO4)3+3H2
51* Write a balanced equation for the complete combustion of each compound. (Page 347) a) butene (C4H8) b) acetone (C3H6O)
a)C4H8+6O2--->4CO2+4H2O b)C3H6O+4O2--->3CO2+3H2O
49* Write a balanced equation for each of the following double replacement reactions: (Page 347) a)H2C2O4 (aq) + KOH (aq) ---> b)CdBr2(aq) + Na2S (aq)---> (calcium sulfide is a precipitate)
a)H2C2O4+2KOH--->K2C2O4+2H2O b)CdBr2(aq)+Na2S(aq)--->CdS+2NaBr(aq)
4) Which substance contains both covalent and ionic bonds? (Page 251) a)NH4No3 b)CH3OCH3 c)LiF d)CaCl2
a)NH4No3
2* Calculate the molar mass of ammonium phosphate, (NH4)3PO4. ( Page 319) a. 149 g/mol b. 113 g/mol c. 242 g/mol d. 121 g/mol
a. 149 g/mol
3* Magnesium nitrate is formed in the reaction of magnesium metal with nitrogen gas. 3Mg(s) + N2(g) ---> Mg3N2 (s) The reaction of 4mol of nitrogen with 6mol of magnesium produces (Page 383) a. 2 mol of Mg3N2 and 2 mol of excess N2 b. 4 mol of Mg3N2 and 1 mol of excess Mg c. 6 mol of Mg3N2 and 3 mol of excess N2 d. no product because the reactants are not in the correct mole ratio.
a. 2 mol of Mg3N2 and 2 mol of excess N2
1* Nitric acid is formed by the reaction of nitrogen dioxide with water 3NO2(g)+H2O(l)---> NO(g)+2HNO3 (aq) How many moles of water are needed to react with 8.4 mol NO2? (Page 383) a. 2.8 mol b. 3 mol c. 8.4 mol d. 25 mol
a. 2.8 mol
47* Write a balanced chemical equation for each decomposition reaction. (Page 347) a) Ag2O (s) --_^_---> ???? b) ammonium nitrate --_^_---> dinitrogen monoxide + water
a. Ag2O(s) --_^_---> 4Ag+O2 b. NH4NO3--_^_--->N2O+2H2O
1 A ) Choose the term that best completes the second relationship. ( Page 319) dozen : eggs mole: a) atoms b) 6.02*10^23 c) size d) grams
b) 6.02*10^23
45* Write balanced chemical equations for the following combination reactions: (Page 347) a) Mg+O2--> b) P+O2--->diphosphorus pentoxide c)Ca+S-->
a.2Mg(s)+O2(g)--->2MgO b. 4P+5O2--->2P2O5 c Ca+S--->CaS
ice cream melts
absorbed
solid-liquid-gas
absorbed absorbed than released
Which type of radiation is the least penetration
alpha
which term best completes the sentence a change in the composition of matter ______ occurs during a chemical reaction
alway
valence electron
an electron of an atom located in the outermost shell of an atom
a bond in which two atoms share a pair of electrons is not
an ionic bond
Spent fuel rods
are stored under water for at least a decase.
flourine
atoms of which element have the greatest tendency to gain electrons?
the species in window a react. use the law of conservation of mass to determine which window best represents the reaction products.
b
4* How many hydrogen atoms are in six molecules of ethylene glycol, HOCH2CH2OH? ( Page 319) a)6 b) 36 c)6*6.02*10^23
b) 36
dissolving steel in acid
chemical
reacts vigorously with flourine
chemical
organic chemists study
chemicals that contain carbon
1* WHen the equation Fe2O3 + H2---> Fe+ H2O is balanced using whole-number coefficients, what is the coefficient of H2? (Page 351) a.6 b.3 c.2 d.1
b.3
S
based on the reference table s, atoms of which of the elements have the strongest attraction for the electrons in a chemical bond?
Which of the following is always true about a battery
batteries use chemicals to store energy
Explain what is meant by bond dissociation energy
bond dissociation is the amount of energy to break a bond
5) Which of these bonds are most polar? (Page 251) a)H-Cl b)H-Br c)H-F d)H-I
c)H-F
1. A bond in which two atoms share a pair of electrons is NOT.. (Page 251) a)a coordinate covalent bond b)a polar covalent bond c)an ionic bond d)a nonpolar covalent bond
c)an ionic bond
inorganic chemists study
chemicals that do not contain carbon
2* Phosphorous trifluoride is formed from its elements. P4(s)+ 6F2 (g) ---> 4PF3(g) How many grams of fluorine are needed to react with 6.2g of phosphorus? (Page 383) a. 2.85 g b. 5.70g c.11.4g d. 37.2g
c.11.4g
for which compound name is the incorrect formula given
calcium oxide, ca2o2
acid rain corroding the statue of liberty
chemical
blue-grey color
chemical
The Japanese characters for chemistry literally mean "change study". Why are these appropriate characters to represent chemistry?
chemistry is concerned with the changes matter undergoes therefor it would make sense that Japanese would consider this a change in study
which of these properties could not be used to distinguish between table salt and sugar
color
Carbon Monoixde
compound
2.How many valence electrons are in a molecule of phosphoric acid H3Po4? (Page 251) a) 7 b) 16 c) 24 d) 32
d)32
7* Which are the expected products of the decomposition reaction of potassium oxide, K2O? (Page 351) a. K+ (s) and O 2- (g) b.K+ (s) and O 2 (g) c.K (s) and O 2 2- (g) d.K(s) and O 2- (g)
d.K(s) and O 2- (g)
if a substance contracts when it freezes its
density will increase
the variable that is observed during an experiment is the
dependent variable
what is the first thing one must do when solving a numeric problem?
determine the knowns and unknowns
two methods of separating mixtures
distillation is used for a homogenous mixture using heat like filtering water filtration is used for a heterogeneous mixture like coffee
gemma particle
doesn't effect the atomic mass or that atomic number
beta particles
doesn't effect the atomic mass, but it increases the atomic number by one
balanced equation
each side of the equation has the same number of atoms of each element and mass is conserved.
Al
electron configuration ending in 3s^2 3p^1: Na, Mg, Al
Ti
electron configuration ending in 4s^2 3d^2: Ca, Sc, Ti
Which of the following properties increases as you move across a period from left to right?
electronegativity and ionization
zinc
element
isoelectric
elements and ions with the same electron configuration
energy levels
elements in the same period have the same number of: protons, energy levels, electrons, valence electrons, or none of these?
Ideally, chemicals used to attack insect pests should be nonspecific because Scientists are looking for safer, more effective ways to protect crops.
false and true For scientists to look for more safe, more effective way to protect crops, the chemicals used to attack the insect pests should be specific.
monitoring exposure to radiation
film badge
C
gas at room temperature: B, C, N
detecting ionizing radiation
geiger counter
which of these bonds is most polar
h-f
mushroom pizza
heterogenous mixture
the melting and boiling points for ionic compounds tend to be
higher than those of covalent bonds
which phrase best describes an apple
homogenous misture
Air
homogenous mixture
3
how many electrons are in lithium?
8
how many electrons does Oxygen have?
20
how many electrons does calcium have?
1
how many valence electrons are in lithium?
2
how many valence electrons does calcium have?
2
how many valence electrons does helium have?
6
how many valence electrons does oxygen have?
by basing it off of atomic radius (energy levels)
if two elements have the same amount of protons and electrons and you are trying to find the ionic radius, how else would you put them in order?
explain the difference between a chemical change and a physical change
in a chemical change a irreversible change has happened as rotting or a color change. In a chemical change the composition is changed in a physical change the composition is not change and can be reversed like melting and dissolving
the variable that you change during an experiment is the
independent variable
which of the following is an example of why an understanding of chemistry is important?
it helps us understand nature, it prepares people for job opportunities, it helps make us informed citizens.
why is it important that scientists collaborate?
it is important for scientists to collaborate to see, if the result are the same or close. Also important for scientists to communicate to see what steps and materials used in the experiment.
Sc
largest atomic mass: K, Ca, Sc
Ta
largest atomic number: V, Nb, Ta
Ga
largest atomic radius: Ga, Al, Si
the state of matter characterized by a definite volume and an indefinite shape is a
liquid
Li, C, F
list these atoms from largest radius to smallest: Li, C, F
activity series
lists metals in order of decreasing reactivity
Which of the following activities involves using the senses to gather information directly?
making an observation
Xe
member of noble gases: Te, I, Xe
Li
member of the alkali metals: Li, Be, B
Cl
member of the halogen family: S, Cl, Ar
Hg
member of the transition metals: Hg, Tl, Pb
Li
metal: Li, Si, S
Bi
metalloid: Pb, Bi, Po
explain why metals produce specific colors of light during flame tests and nonmetals do not
metals require an amount of energy to move energy levels, when the atom releases energy it produces light.
milk can be purchased in many different varieties including skim 1%, 2%, whole or cream explain how this information can help one decide whether mild is a substance or a mixture
milk is a mixture because there is one or more more things in mild. there's fat and water and cow blood. a substance has a uniformed fixed composition.
which of these series of units is ordered from smallest to largest?
mm,dm,m,km
more shielding
more energy levels means?
detecting art forgeries
neutron activation analysis
H
nonmetal: H, Li, Na
which of these molecules can form a hydrogen bond with a water molecule
o2
boiling salt water until just salt remians
physical
brittle
physical
cracking ice
physical
dissolving salt in water
physical
doesn't dissolve in water
physical
melting steel
physical
melts at 1410 degrees celsius
physical
Cl, Si, Mg
put the elements in order from greatest electronegativity to least: Mg, Si, Cl
S, Si, Mg
put the elements in order from greatest ionization energy to least: S, Si, Mg
Cl, Si, Mg
put the elements in order of greatest nonmetal activity to the least nonmetal activity: Mg, Si, Cl
Br^- , Cl^- , F^-
put the ions in order from largest radius to smallest: F^- , Cl^-, Br^-
I, Cl, F
put these elements in order from most meal activity to least: F, Cl, I
treating come cancers
radiation therapy
diagnosing some diseases
radioactive tracer
water freezes
released
water vapor condenses
released solid
coefficients
small whole numbers that are placed infront of the formulas in an equation in order to balance it.
As
smallest ionization energy: N, P, As
Why do compounds with strong intermolecular attractive forces have higher boiling points than compounds with weak intermolecular attractive forces
strong intermolecular have higher boiling points because it requires more energy to break the bong.
Beryllium
s²
Strontium
s²
alpha particle
the atomic mass is decrease by 4. The atomic number is decreased by 2.
if a radioisotope undergoes beta emmision
the atomic number changes
analytical chemists study
the composition of matter
sodium
the element in period 3 with the largest atomic radius is: sodium, chlorine, magnesium, or argon?
As the wavelength of light increase
the frequency decreases
physical chemists study
the mechanism, rate, and energy transfer as matter undergoes change
In what way were alchemists like modern scientists
they developed techniques for working with matter.
The supply of fossil fuels is limited because scientists are always looking for new sources of energy
true and true To meet the demand of fossil fuels, scientist would look for alternate sources of energy. The statements don't explain why the supply of fossil fuels are limited.
1000m
unlimited
25
unlimited
60s
unlimited
which type of intermolecular attraction is responsible for a gecko's ability walk on the ceiling?
van de waals force
a
what causes the shielding effect to remain constant across a period? a.)electrons are added to the same principal energy level (b) the charge on the nucleus is constant (c) the atomic radius increases (d) electrons are added to different principal energy levels
O
what element has the least ionization energy: Ge, P, O
increasing electronegativity
what general trend is found in period 3 as the elements are considered in order of increasing atomic number?
1 group
what group is Na in?
[Ne]
what is the noble gas configuration for Na^1+
1s^2 2s^1
whats the electron configurations for lithium
Cl atom
which atom has the weakest attraction for the electrons in a bond with an H atom?
a decrease in electronegativity
which general trend is demonstrated by the group 17 elements as they are considered in order from top to bottom on the periodic table?
metals
which of the following categories includes the majority of the elements? nonmetals, metals, metalloids, or liquids
iodine
which of the following elements has the largest atomic radii? phosphorus, carbon, chlorine, iodine
the fewer valence electrons the less stable it is
why is the valence shell so important in studying chemical reactions?
1
within a period, the element with the lowest first ionization energy is found in group: 1, 11, 14, 17, or 18?
1s^2 2s^2 2p^6 3s^2 3p^6 4s^1
write the electron configuration for calcium
1s^2 2s^2 2p^4
write the electron configuration for oxygen
1s^2 2s^2 2p^6 3s^2 3p^6 or [Ar]
write the electron configuration of the ion: Ca^+2
1s^2 2s^2 2p^6 or [Ne]
write the electron configuration of the ion: Na^+
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6
write the electron configuration of the ion: Se^-2
1s^2
write the noble gas configuration for helium
[He]2p^3
write the noble gas configuration for nitrogen
Chemists who work in the biotechnology field are most likely to be
x-ray technicians
An atom composed of 16 protons, 16 electrons, and 16 neutrons is
³²₁₆S
Which of these series of units is ordered from smallest to largest?
(weird u)s, ns, cs, s
An over the counter medicine has 325 mg of its active ingredient per tablet. How many grams does this mass represent?
0.325g
In the third energy level
A maximum of 18 electrons are allowed
Identify each as a mixture or compound,classify the mixtures as homogenous or heterogeneous: A.raw egg B.ice C.gasoline D.blood
A.heterogeneous mixture B.compound C.homogenous mixture D.heterogeneous mixture
Describe clues you might observe during the folloing events that could support the conclusion yhat a chemical change is occuring A.an antacid tablet is dropped into water B.a ring of scum forms around a bathtub C.iron rusts D.a firecracker explodes
A.look for a new substance being formed B.look for a solid substance, a precipitate being formed around bathtub C.look for color and texture change D.look for energy and odor change
Assify rhe folllowing properties of the element silicon as chemical or physical properties A.blue-grey color B.brittle C.Doesn't disolve in water D.melts at 1410C E.reacts vigorously with flourine
A.physical B.physical C.physical D.physical E.chemical
List the symbols for sodium, sulfur and celsium in order of increasing atomic radii.
Atomic size increases as you go from top to bottom within a group, decreases from left to right across a period. Cs, Na, S
Thallium has two isotopes, thallium-203 and thallium-205. Thallium's atomic number is 81 and its atomic mass is 204.38 amu. Which statement about the thallium isotopes is true?
Atoms of both isotopes have 81 protons.
The state of matter characterized by a definite volume and an indefinite shape is a: A.solid B.liquid C.mixture D.gas
B
The inner transition metal with the lowest atomic number
Ce
9* Which choice describes what happens as each of the following elements forms its ion? (Page 211) cesium
Cesium is located in Group 1A and has one valence electron. Therefore, one electron must be removed from cesium in order to obtain an electron configuration of a noble gas
The number that appears in front of a formula in a balanced equation is the _____________
Coefficient
Which of these properties could not be used to distinguish between table salt and table sugar? A.boiling point B.melting point C.density D.color
D
A ____________________ reaction is a chemical change that involves an exchange of positive ions between two compounds
Double replacement
Which of these descriptions is incorrect, fix it.
Electron is not in the nucleus.
Which of the following properties increases as you move across a period from left to right? I. electronegativity II. ionization energy III. Atomic radius
Electronegativity and ionization energy
Explain why fluorine has a smaller atomic radius than both oxygen and chlorine?
Fluorine is keeping it's electron very close to the nucleus. Making the atomic radius smaller. Atomic radius trend goes from left to right that atomic radius decreases. The atomic radius increases from top to bottom.
Is malleability an extensive or intensive property? Explain
Intensive Depends on the characteristic or type of matter in a sample
7* Which choice describes what happens as each of the following elements forms its ion? (Page 211) iodine
Iodine is located in Group 7A and has seven valence electrons. Therefore, one electron must be added to iodine in order to obtain an electron configuration of a noble gas.
Which are the expected products of the decomposition reaction of potassium oxide, K2O?
K(s() and O2(g)
To write a skeleton equation, write the chemical formulas for the reactance to the __________ of the yield sign (arrow) and the formula for the products to the ___________
Left,right
8* Which choice describes what happens as each of the following elements forms its ion? (Page 211) magnesium
Magnesium is located in Group 2A and has two valence electrons. Therefore, two electrons must be removed from magnesium in order to obtain an electron configuration of a noble gas
Would you expect metals or nonmetals in the same period to have higher ionization energies?
Nonmetals would have a higher ionization energies because it's harder to remove an electron form a nonmetal. Nonmetals want to gain electrons not give away electrons. Ionization trend increase form left to right and decrease from top to bottom.
The electron configuration for an element in the halogen group should always end with
Ns2Np5
List the symbols for sodium, sulfur, and cesium in over of increasing atomic radii
S, Na, Cs
To write a balanced chemical equation, first right the ____________
Skeleton equation
And ion that appears on both sides of an equation and is not directly involved in the reaction, is called a ______________
Spectator ion
liquid
The state of matter characterized by a definite volume and an indefinite shape is a
heterogeneous mixture
Which description correctly identifies a mushroom pizza?
homogeneous mixture
Which description correctly identifies air (at sea level)?
element
Which description correctly identifies zinc?
Potassium, P
Which element is paired with the wrong symbol?
paper being shredded
Which of the following is not a chemical change?
color
Which of these properties could not be used to distinguish between table salt and table sugar?
heterogeneous mixture
Which phrase best describes an apple?
triple covalent bond
a bond formed by shared three pairs of electrons
skeleton equation
a chemical equation that does not indicate relative amounts of reactants and products
molecular compound
a compound composed of molecules
chemical equation
a concise representation of a chemical reaction
coordinate covalent bond
a covalent bond in which one atom contributes both bonding electron
bonding orbital
a molecular orbital that can be occupied by two valence electrons of a covalent bond
diatomic molecule
a molecule that contains two atoms
product
a new substance formed in a chemical reaction
reactant
a starting substance in a chemical reaction
Which sphere would most likely represent K⁺?
a the smaller one
3* How many valence electrons does arsenic have ? (Page 211) a) 5 b) 4 c) 3 d) 2
a) 5
balanced equation
an equation in which each side has the same number of atoms of each element
resonance structures
are structures that occur when it is possible to draw two or more valid electron dot structure that have the same number of electron pair for a molecule or ion
covalent bond
atoms are held together by sharing electrons
a. Which sphere would most likely represent K?
b the larger one. (atom is always bigger than ion)
5*Which electron configuration represents a nitride ion (Page 211) a) 1s2 2s2 3s2 4s2 b) 1s2 2s2 2p3 c) 1s2 2s2 2p6 d) 1s2
c) 1s2 2s2 2p6
1* Which of these is an ionic compound ? (Page 211) a) KF b) Na2So4 c) SiO2 d) Na2O
c) SiO2
4* For which compound name is the incorrect formula given: (Page 211) a) magnesium iodide, MgI2 b) potassium selenide, K2Se c) calcium oxide, Ca2O2 d) aluminum sulfide Al2S3
c) calcium oxide, Ca2O2
6*When a Bromine atom gains an electron .. (Page 211) a) a bromine ion is formed b) the ion formed has a 1- charge c) the ion formed is an anion. d) all the above are correct
d) all the above are correct
2*Which statements are correct when Barium and Oxygen react to form an ionic compound: | Barium atoms lose 2 electrons and form a cation || Oxygen atoms form oxide anions(O2-) ||| In the compound the ions are present in a one-to-one ratio. (Page 211) a) | & || only b) || & ||| only c) | & ||| only d) |,|| and |||
d) |,||, and |||
tetrahedral angle
in this arrangement all of the H-C-H angles are 109.5
double covalent bond
is a bond that involves two shared pairs of electrons
polar bond
is a covalent bond between atoms in which the electrons are shared unequally
molecules
is a neutral group of atoms joined by covalent bonds
polyatomic ion
is a tightly bound group of atoms that has a positive or negative charge and behaves as a unit
If the spheres represent an atom and an anion of the same element, which sphere represents the atom and which represents the anion?
it would still be the same, unless they are nonmetals, in that case the ion is much larger than the atom.
6. When a substance freezes it will?
its density will increase.
Dipole interactions
occur when polar molecules are attracted to one another
polar molecule
one end of the molecule is slightly negative and the other end is slightly positive.
molecular orbitals
orbitals that apply to the entire molecule
structural formula
represents the covalent bonds by dashes and shows the arrangement of covalently bonded atoms
hybridization
several atomic orbitals mix to form the same total number of equivalent hybrid orbitals
VSEPR theory
states that the repulsion between electron pairs causes molecular shapes to adjust so that the valence-electron pairs as far apart as possible
Germanium
s²p²
Sulfur
s²p⁴
Krypton
s²p⁶
pi bond
the bonding electrons are mostly likely to be found in sausage shaped regions above and below the bond axis of the bonded atoms
nonpolar covalent bond.
the bonding electrons are shared equally and each bond formed
molecular formula
the chemical formula of a molecular compound
bond dissociation energy
the energy required to break the bond between two covalently bonded atoms
van der Waals forces
the two weakest attractions between molecules are collectively called
single covalent bond
two atoms held together by sharing one pair of electrons are joined by
sigma bond
when two atomic orbitals combine to form a molecular orbital that is symmetrical around the axis connecting two atomic nuclei