Deck 6: Chemical Composition

Question 1

One mole of I₂ has more atoms in it than one mole of Na.

Answer 1

True

Question 2

The molar mass of a compound in grams per mole is numerically equal to the formula mass of the compound in atomic mass units.

Answer 2

True

Question 3

One mole of water contains 16 grams of oxygen atoms.

Answer 3

True

Question 4

One mole of zinc contains 65.39 zinc atoms.

Question 5

One mole of argon has more atoms in it than one mole of neon.

Question 6

Avogadro's Number is 6.022 × 10²³.

Question 7

The mass of 2.0 moles of H₂O is greater than the mass of 1.0 mole of CO₂.

Question 8

One mole of chlorine gas has a mass of 35.45 grams.

Question 9

The lighter the atom,the less mass in one mole of that atom.

Question 10

One mole of CO₂ gas contains 1 mole of carbon atoms and 2 moles of oxygen atoms.

Question 11

Two moles of cobalt atoms have a mass of 117.87 grams.

Question 12

One mole of nitrogen gas contains (2)× (6.022 × 10²³)nitrogen atoms.

Question 13

The numerical value of the mole is defined as being equal to the number of atoms in exactly 12 grams of pure carbon-12.

Question 14

The mole has a value of 6.023 × 10²².

Question 15

One mole of copper atoms is 6.022 × 10²³ copper atoms.

Question 16

One hundred nickels must have the same mass as one hundred pennies.

Question 17

Six grams of carbon contains 3.008 × 10²³ atoms.

Question 18

The number 6.022 × is six times larger than the number 6.022 × .

Question 19

Mass is used as a method of counting atoms.

Question 20

The chemical formula clearly indicates the relationship between the mass of each element in the formula.

Question 21

The molecular formula is equal to the empirical formula multiplied by a whole number integer.

Question 22

An empirical formula gives the specific number of each type of atom in a molecule.

Question 23

C₂H₃O₂ could be an empirical formula.

Question 24

The correct formula for calculating mass percent of X in compound XY is: = Mass % X

Question 25

C₂H₆O₄ could be an empirical formula.

Question 26

Water is 11.2% hydrogen by mass.

Question 27

One mole of lead(II)nitrate contains six moles of oxygen atoms.

Question 28

The empirical formula mass must be 25.0 if the molecular formula mass is 250 and n = 5.

Question 29

A molecule that has an empirical formula of HO and a molar mass of 34.02 gram must have a molecular formula of H₂O₂.

Question 30

The chemical formula CuBr₂ indicates that this compound is composed of 1 gram of copper and of bromine.

Question 31

Which of the following statements about the mole is FALSE?

A)One mole of atoms makes up an amount of atoms that can be seen with the naked eye.
B)A mole of a monatomic element corresponds to one Avogadro's number of atoms.
C)One mole of a monatomic element has a mass equal to its atomic mass expressed in grams.
D)One mole of water contains 1/2 mole of oxygen atoms.
E)none of the above

Question 32

There are 6 grams of carbon in 22 grams of carbon dioxide.

Question 33

An empirical formula gives the smallest whole number ratio of each type of atom in a molecule.

Question 34

One mole of water contains 6.022 × 10²³ hydrogen atoms.

Question 35

The empirical formula for C₆H₆ is C₃H₃.

Question 36

One half of a mole of atoms would contain how many atoms?

A)0.5
B)3.011 × 10²³
C)6.022 × 10²³
D)6.022 × 10^11.5
E)none of the above

Question 37

The molar mass of a compound serves as a conversion factor between grams and moles.

Question 38

What is the correct value for Avogadro's number?

A)6.022 × 10²³
B)6.022 × 10³³
C)6.023 × 10²²
D)6.022 × 10^2.3
E)none of the above

Question 39

C₂H₆O₃ could be an empirical formula.

Question 40

The empirical formula mass is 18.0 and the molecular formula mass is 90,therefore n = 5.

Question 41

You have 10.0 g each of Na,C,Pb,Cu and Ne.Which contains the largest number of moles?

A)Na
B)C
C)Pb
D)Cu
E)Ne

Question 42

What is the mass in grams of 5.40 moles of lithium?

A)6.94
B)37.5
C)1.29
D)3.25 × 10²⁴
E)none of the above

Question 43

How many atoms are in 15.6 grams of silicon?

A)2.64 × 10²⁶
B)3.34 × 10²³
C)0.555
D)438
E)none of the above

Question 44

How many moles of Cu are in 1.48 × 10²⁵ Cu atoms?

A)0.0408
B)24.6
C)1.54 × 10²⁵
D)6.022 × 10²³
E)none of the above

Question 45

In comparing 1 mole of carbon atoms to one mole of magnesium atoms,which statement is TRUE?

A)The mass of 1 mole of carbon is greater than the mass of 1 mole of magnesium.
B)The mass of 1 mole of magnesium is greater than the mass of 1 mole of carbon.
C)The mass of 1 mole of carbon is the same as the mass of 1 mole of magnesium.
D)There are more atoms in 1 mole of magnesium than in 1 mole of carbon.
E)none of the above

Question 46

How many moles of bromine gas are in 37.7 grams?

A)0.236
B)0.472
C)3.01 × 10³
D)79.9
E)none of the above

Question 47

You have 10.0 g each of Na,C,Pb,Cu and Ne.Which contains the smallest number of moles?

A)Na
B)C
C)Pb
D)Cu
E)Ne

Question 48

How many atoms are in 1.50 moles of fluorine gas?

A)6.022 × 10²³
B)9.03 × 10²³
C)18.98
D)1.81 × 10²⁴
E)none of the above

Question 49

What is the mass of 0.560 moles of chlorine gas?

A)19.9
B)63.3
C)127
D)39.7
E)none of the above

Question 50

One mole of boron has a mass of ________ g.

A)9.012
B)6.022 × 10²³
C)5
D)10.811
E)none of the above

Question 51

How many moles are there in 17.5 grams of sodium?

A)22.99
B)1.05 × 10²⁵
C)0.761
D)1.31
E)none of the above

Question 52

How many atoms are in 5.80 moles of He?

A)6.02 × 10²³
B)1.03 × 10²³
C)4.00
D)3.49 × 10²⁴
E)none of the above

Question 53

What is the mass of 1.56 × 10²¹ atoms of magnesium in grams?

A)4.72 × 10^-5
B)0.0630
C)0.142
D)1.07 × 10^-4
E)none of the above

Question 54

In comparing a balloon containing 25 grams of helium to a balloon containing 25 grams of neon,which one of the following statements is TRUE?

A)Each balloon has an equal number of atoms.
B)The helium balloon has more atoms.
C)The neon balloon has more atoms.
D)This scenario cannot happen because gases have no mass.
E)none of the above

Question 55

How many moles of iron are contained in 1.75 kg of iron?

A)3.13 × 10^-2
B)3.13 × 10^-4
C)31.3
D)3.13 × 10⁴
E)none of the above

Question 56

How many moles of Pb are in 4.71 × 10²¹ Pb atoms?

A)0.00782
B)2.84 × 10⁴⁵
C)207.2
D)6.022 × 10²³
E)none of the above

Question 57

One mole of oxygen gas has a mass of ________ g.

A)16.0
B)32.0
C)6.022 × 10²³
D)8
E)none of the above

Question 58

How many moles are there in 82.5 grams of iron?

A)4.97 × 10²⁵
B)55.85
C)0.677
D)1.48
E)none of the above

Question 59

What is the mass of 3.09 × 10²⁴ atoms of sulfur in grams?

A)9.64 × 10²²
B)9.91 × 10²⁵
C)165
D)0.160
E)none of the above

Question 60

How many hydrogen atoms are in 35.0 grams of hydrogen gas?

A)4.25 × 10²⁵
B)2.09 × 10²⁵
C)2.12 × 10²⁵
D)1.05 × 10²⁵
E)none of the above

Question 61

How many molecules of sulfur trioxide are in 78.0 grams?

A)5.87 × 10²³
B)7.33 × 10²³
C)3.76 × 10²⁷
D)0.974
E)none of the above

Question 62

What is the molar mass of aluminum sulfate?

A)123.0 g/mol
B)278.0 g/mol
C)306.2 g/mol
D)315.2 g/mol
E)342.2 g/mol

Question 63

A 500.gram iron ore sample was determined to contain 242 grams of iron.What is the mass percent of iron in the ore?

A)93.7
B)48.4
C)51.6
D)32.6
E)none of the above

Question 64

A 42.7 gram sample of potassium nitrate contains how many grams of potassium?

A)39.1
B)16.5
C)21.4
D)8.54
E)none of the above

Question 65

If 3.011 ×10²³ molecules have a mass of 20.04 grams,what is the molar mass of this substance?

A)40.08 g/mol
B)10.02 g/mol
C)20.04 g/mol
D)6.658 × g/mol
E)none of the above

Question 66

One mole of potassium sulfate contains:

A)4 moles of oxygen.
B)2 moles of sulfur.
C)1 mole of potassium.
D)3 moles of potassium.
E)none of the above

Question 67

Calculate the molar mass of calcium nitrate.

A)136.03 g/mol
B)102.09 g/mol
C)132.10 g/mol
D)164.10 g/mol
E)none of the above

Question 68

Which of the following contains 9.02 × 10²³ atoms?

A)4.00 g H₂
B)9.00 g H₂O
C)28.0 g N₂
D)32.0 g O₂
E)none of the above

Question 69

The mass of one mole of carbon dioxide is ________ g.

A)28.01
B)384.4
C)32.00
D)44.01
E)none of the above

Question 70

One mole of (NH₄)₂HPO₄ contains how many moles of hydrogen atoms?

A)4
B)2
C)8
D)9
E)none of the above

Question 71

How many moles of carbon are in 3.5 moles of calcium carbonate?

A)10.5
B)3.5
C)7
D)100.09
E)none of the above

Question 72

How many moles of fluorine are in 3.2 moles of xenon hexafluoride?

A)22.4
B)12.8
C)19.2
D)16
E)none of the above

Question 73

If a sample of carbon dioxide contains 3.8 moles of oxygen atoms,how many moles of carbon dioxide are in the sample?

A)1.9
B)3.8
C)7.6
D)11.4
E)none of the above

Question 74

How many molecules of nitrogen monoxide are in a 22.5 gram sample?

A)5.86 × 10²³
B)7.33 × 10²³
C)4.51 × 10²³
D)4.06 × 10²³
E)none of the above

Question 75

One mole of ammonium nitrate contains:

A)3 moles of hydrogen.
B)2 moles of oxygen.
C)2 moles of nitrogen.
D)1 mole of nitrogen.
E)none of the above

Question 76

If 2.01 × atoms of an element from Group IA of the periodic table has a mass of 7.675 grams,this element is most likely:

A)Li.
B)Na.
C)K.
D)Rb.
E)Cs.

Question 77

An iron ore sample is found to be 35.00% Fe by mass.How many grams of ore are needed to obtain of Fe?

A)1297
B)158.9
C)295.1
D)350.0
E)none of the above

Question 78

A 15.5 gram sample of diphosphorous pentoxide contains how many grams of phosphorous?

A)3.38
B)1.69
C)6.76
D)13.5
E)none of the above

Question 79

Calculate the molar mass of ammonium carbonate.

A)78.05 g/mol
B)88.05 g/mol
C)96.09 g/mol
D)112.09 g/mol
E)none of the above

Question 80

One mole of ammonium nitrite contains:

A)2 moles of nitrogen atoms.
B)4 moles of hydrogen atoms.
C)2 moles of oxygen atoms.
D)All of A,B,and C.
E)None of A,B,and C.