Chemistry Exam #4 Ch. 7&8 #'s 1-59

One mole of particles of any substance contains how many particles?

6.02 � 1023 particles

Avogadro's number is the number of ________.

particles in 1 mole of a substance

One mole of copper(II) sulfate, CuSO4, contains ________ O atoms

2.41 � 1024

0.400 mole of sucrose, C12H22O11, contains ________ C atoms

2.89 � 1024

One mole of copper(II) sulfate, CuSO4, contains ________ moles of O.

4

0.400 mole of sucrose, C12H22O11, contains ________ moles of C.

6.02 � 1023

How many moles of carbon atoms are there in 0.500 mole of C2H6?

1.00 mole

The molar mass of potassium is ________.

39.10 g/mole

One mole of helium gas weighs ________.

4.003 g

Calculate the molar mass of potassium chloride, KCl.

74.55 g/mole

What is the molar mass of copper(II) sulfate, CuSO4?

159.6 g/mole

Calculate the molar mass of magnesium chloride, MgCl2.

95.21 g/mole

What is the molar mass of sodium phosphate, Na3PO4?

163.9 g/mole

What is the molar mass of sucrose (C12H22O11)?

342.3 g/mole

One mole of neon atoms has a mass of ________.

20.18 g

The molar mass of C3H8O2 is ________.

76.09 g/mole

The molar mass of calcium hydroxide, Ca(OH)2, is ________.

74.10 g/mole

What is the molar mass of Mg3(PO4)2, a substance formerly used in medicine as an antacid?

262.9 g/mole

How many moles of water, H2O, are present in 75.0 g H2O?

4.16 moles

0.100 mole of lithium has a mass of ________.

0.694 g

4.00 moles of sodium have a mass of ________.

92.0 g

How many moles of K2SO4 are in 15.0 g of K2SO4?

0.0861 moles

3.00 moles of NO2 have a mass of ________.

138 g

How many grams of Fe2O3 are there in 0.500 mole of Fe2O3?

79.9 g

How many grams of glucose (C6H12O6) are in 3.55 moles of glucose?

640. g

A chemical equation is balanced when ________.

the number of atoms of each element is the same in reactants and products

In any balanced chemical equation, the number of each type of atom on both sides of the equation is ________.

the same

Which of the following gives the balanced equation for this reaction?

2K3PO4 + 3Ca(NO3)2 Ca3(PO4)2 + 6KNO3

Which of the following correctly gives the correct coefficients for the reaction below?

1, 2, 1, 4

What coefficient is placed in front of O2to complete the balancing of the following equation?

7

What is the coefficient of hydrogen,H2, when the following equation is balanced?

3

C5H12+ ? O2 ? CO2 + ? H2O

using for the next questions

What is the coefficient for oxygen in the balanced equation?

8

What is the coefficient for carbon dioxide in the balanced equation?

5

What is the coefficient for water in the balanced equation?

6

In this reaction, what is the coefficient for calcium oxide?

1

In this reaction, what is the correct coefficient for sodium chloride?

2

In the following reaction, what is the correct coefficient for aluminum chloride?

2

For the following reaction, what is the correct coefficient for the H2?

3

What is the classification for this unbalanced reaction?

single replacement

In a ________ reaction, two or more elements or compounds form one product.

combination

The following reaction is an example of a ________ reaction.

single replacement

The following reaction takes place when an electric current is passed through water. It is an example of a ________ reaction.

decomposition

What is the classification for this reaction?

combination

The reaction of carbon with oxygen to produce carbon monoxide is an example of which class of reaction?

combination

Which of the following is an oxidation-reduction reaction?

N2 + O2 2NO

What is oxidized and what is reduced in the following reaction?

Al is oxidized and Br2 is reduced.

In an oxidation-reduction reaction, the substance oxidized always ________.

loses electrons

In this reaction, what is the substance oxidized?

zinc

In an oxidation-reduction reaction, the substance reduced always ________.

gains electrons

Given the following equation, what is the correct form of the conversion factor needed to convert the number of moles of O2 to the number of moles of Fe2O3 produced?

2 moles Fe2O3/3 moles O2

2Mg + O2 2MgO

Use for the next questions

The number of moles of oxygen gas needed to react with 4.0 moles of Mg is ________.

2.0 moles

The number of moles of MgO produced when 0.20 mole of O2 reacts completely is ________.

0.40 mole

Mg3N2 + 6H2O 3Mg(OH)2 + 2NH3

Use for the next questions

What is the correct form of the conversion factor needed to convert the number of moles of H2O to the number of moles of NH3 produced?

2 moles NH3/6 moles H2O

When 2 moles of Mg3N2 are allowed to react, how many moles of H2O also react?

12 moles

When 4 moles of aluminum are allowed to react with an excess of chlorine gas, Cl2, how many moles of aluminum chloride are produced?

4 moles

In the reaction of nitrogen gas, N2, with hydrogen gas, H2, to form ammonia gas, NH3, how many moles of hydrogen are needed to react with two moles of nitrogen?

6 moles

2Mg + O2 2MgO

Use for the next questions

How many grams of magnesium are needed to react with 16 g of O2?

24 g

How many grams of MgO are produced when 40.0 grams of O2 react completely with Mg?

101 g

How many grams of hydrogen are needed to produce 1.80 g of water according to this equation?

0.201 g