Chemistry 1: Module 2

If two different nuclides have the same mass number, it must mean that

the combined number of protons and neutrons are the same.

If two different nuclides have the same atomic number, it must mean that

they have the same number of protons.

The species that is formed when a molecule gains or loses an electron is called

an ion

A 2.0-g sample of washing soda, Na2CO3 • 10H2O, has carbon atoms. How many oxygen atoms are present in 2.0g of washing soda?

5.5 x 10^22

The systematic name for BaH2 is

barium hydride

Which of the following statements about different elements is/are true? 1. As is a metalloid and Se is a nonmetal. 2. Cu is a transition element and Ge is a metalloid. 3. Both F and I are halogens.

1, 2, and 3

Which of the following nuclides contains more protons than neutrons?

1/1 H

Ammonia can be made by reaction of water with magnesium nitride: __ Mg3N2(s) + __ H2O(l) → __ Mg(OH)2(s) + __ NH3(g) When the equation is properly balanced, the sum of the coefficients is

12

When the equation __ C5H6N2OS(s) + __ O2(g) → __ CO2(g) + __ H2O(l) + __ N2(g) + __ SO2(g) is balanced, the sum of all the coefficients (simplest whole number) is

18

The complete combustion of phenylhydrazine, C6H5NHNH2, with the oxidizer dinitrogen tetraoxide is shown in the following equation: __ C6H5NHNH2 + __ N2O4 → __ CO2 + __ H2O + __ N2 When this equation is balanced, the sum of all the coefficients (using smallest whole numbers) is

20

What is the symbol of the nuclide having 13 protons and 14 neutrons?

27/13 Al

Which is a correct balanced chemical equation corresponding to the following description of a chemical reaction? Hydrochloric acid reacts with magnesium metal to produce aqueous magnesium chloride and hydrogen gas.

2HCl(aq) + Mg(s) → MgCl2(aq) + H2(g

Energy from the following reaction provided the lift for the moon lander: __ (CH3)2N2H2 + __ N2O4 → __ N2 + __ H2O + __ CO2 When the equation is balanced, the smallest whole-number coefficient of nitrogen is

3

How many neutrons are there in the cobalt-59 nuclide?

32

The average atomic mass of Eu is 151.96 amu. There are only two naturally occurring isotopes of europium, 151Eu with a mass of 151.0 amu and 153Eu with a mass of 153.0 amu. The natural abundance of the 131Eu isotope must be approximately

50 %

The complete combustion of pentane yields carbon dioxide and water. When the equation __ C5H12(l) + __ O2(g) → __ CO2(g) + __ H2O(l) is balanced, the ratio of the coefficient of CO2 to the coefficient of O2 is

5:8

An atom that has the same number of neutrons as 59Ni is

60 Cu

A sample of the mineral troegerite, (UO2)3(AsO4)2 • 12H2O, has 1.34 × 1021 U atoms. How many arsenic atoms are present in this sample of troegerite?

8.93 x 10^20

Which of the following atomic symbols represents an isotope of 94Mo?

95Mo

The formula for aluminum bromide is

Al Br3

The formula for aluminum chloride is

AlCl3.

Which of the following statements about different elements is incorrect?

Aluminum is a transition element.

Suppose atom 1 has the same number of protons as atom 2, and atom 2 has the same number of neutrons as atom 3. Atom 1 does not have the same number of neutrons as atom 3. Which of the following statements is true?

Atoms 1 and 2 must be isotopes.

Bismuth(III) sulfate is an ionic compound formed from Bi3+ and SO42-. What is the correct way to represent the formula?

Bi2(SO4)3

Choose the name-formula pair that does not match. a. potassium permanganate, K2MnO4 b. aluminum oxide, Al2O3 c. sodium sulfite, Na2SO3 d. calcium fluoride, CaF2 e. iron(III) oxide, Fe2O3

potassium permanganate, K2MnO4

Which of the following molecules is a hydrocarbon? a. H2O b. CH3CH2OH c. CH3CH2CH3 d. C6H12O6 e. CH3OCH3

CH3CH2CH3

Which of the following molecules contains the ether functional group? a. H2O b. CH3CH2OCH2CH3 c. CH3CH2NH2 d. CH3CH2OH e. CH3CH2COOH

CH3CH2OCH2CH3

Which of the following molecules contains the alcohol functional group?

CH3OH

The formulas of the carbonate ion, the ammonium ion, and the chlorate ion are represented, respectively, as

CO32-, NH4+, ClO3-.

What is the formula for calcium nitride?

Ca3N2

The formula of calcium sulfide is

CaS

Which of the following is the atomic symbol for the element cobalt?

Co

Which of the following equations is not balanced? a. 2Sb2OS2 + 10O2 → 2Sb2O5 + 4SO3 b. (NH4)2Cr2O7 → N2 + 4H2O + Cr2O3 c. C12H22O11 + 12O2 → 12CO2 + 11H2O d. 2NaCl + Pb(NO3)2 → PbCl2 + 2NaNO3 e. Fe3O4 + 3CO → 3Fe + 3CO2

Fe3O4 + 3CO → 3Fe + 3CO2

Which of the following equations is not balanced? a. 2Sb2OS2 + 10O2 → 2Sb2O5 + 4SO3 b. C12H22O11 + 12O2 → 12CO2 + 11H2O c. Fe3O4 + 3CO → 3Fe + 3CO2 d. 2NaCl + Pb(NO3)2 → PbCl2 + 2NaNO3 e. (NH4)2Cr2O7 → N2 + 4H2O + Cr2O3

Fe3O4 + 3CO → 3Fe + 3CO2Fe3O4 + 3CO → 3Fe + 3CO2

What is the formula for the chloride of gadolinium(III)?

GdCl3

Which of the following represents a pair of isotopes? Atomic Number Mass Number

I 17 35 II 17 37

The formula for potassium carbonate is

K2CO3.

Which of the following is an ionic compound?

NH4CN

Which of the following pairs of compounds can be used to illustrate the law of multiple proportions? a. ZnO2 and ZnCl2 b. H2O and HCl c. CH4 and CO2 d. NH4 and NH4Cl e. NO and NO2

NO and NO2

The formulas of the hydroxide ion, the nitrate ion, and the phosphate ion are represented, respectively, as

OH-, NO3-, PO4^3-.

Who discovered the nucleus of an atom?

Rutherford

Which of the following statements best describes the particulate representation depicted by the picture?

The figure is a representation of a gas made up of a single element.

What is the formula for the chlorate of ytterbium(III)?

Yb(ClO3)3

A certain element is listed as having an atomic mass of 63.5 amu. It is probably true that this element contains

a mixture of isotopes.

If the Thomson model of the atom had been correct, Rutherford would have observed

alpha particles going through the foil with little or no deflection.

What is the name of the compound whose formula is Al2(SO4)3?

aluminum sulfate

Choose the name-formula pair that does not match. a. sodium chlorite, NaClO2 b. ammonium hydrogen carbonate, NH4CO3 c. calcium hydroxide, Ca(OH)2 d. nitric acid, HNO3 e. calcium hydride, CaH2

ammonium hydrogen carbonate, NH4CO3

An ion is formed

by either adding electrons to or subtracting electrons from the atom.

According to the law of multiple proportions: a. the total mass is the same after a chemical change as before the change. b. it is not possible for the same two elements to form more than one compound. c. the ratio of the masses of the elements in a compound is always the same. d. if the same two elements form two different compounds, they do so in the same ratio. e. none of these

none of these

Which of the following is a metalloid?

silicon

The chemical name for the model is (two Nitrogens and four oxygens)

dinitrogen tetroxide.

A periodic law based on atomic masses would necessitate Te and I changing places in the periodic table. This was not done in the early periodic table because a. it was thought that the atomic masses might be in error. b. iodine contains one naturally occurring isotope, whereas tellurium consists of several isotopes. c. iodine behaves chemically like chlorine and bromine. d. a periodic law based on atomic masses is not valid. e. the tellurium samples could contain a heavy impurity.

iodine behaves chemically like chlorine and bromine.

The correct name for FeO is

iron(II) oxide.

The elements in groups 1A-8A or 1-2 and 15-18 are known as the

main group

The names of the elements whose symbols are Si, P, Mn, and S are, respectively,

silicon, phosphorus, manganese, and sulfur.