Q: Which of the following is a correct mole relationship for 1 mole of $$\mathrm{BaCl}_2$$?

$$1$$ mole $$\mathrm{BaCl}_2$$ contains $$2 \times 6.02 \times 10$$^{23}$$ $$\mathrm{Cl}^-$$ ions.

Question 1

Which of the following best describes the law illustrated by the balanced chemical equation $$2 \mathrm{H}_2 + \mathrm{O}_2 \rightarrow 2 \mathrm{H}_2\mathrm{O} as $$shown in the image?

Accepted Answer

The law of conservation of mass

Question 2

In the reaction $$2 \mathrm{H}_2 + \mathrm{O}_2 \rightarrow 2 \mathrm{H}_2\mathrm{O}$$, what is the correct mole ratio of hydrogen to oxygen to water?

Accepted Answer

$$2:1:2$$

Question 3

If you start with 5.0 mol of $$\mathrm{H}_2$$ and 2.0 mol of $$\mathrm{O}_2$$, how many moles of $$\mathrm{H}_2\mathrm{O}$$ can be produced according to the reaction $$2 \mathrm{H}_2 + \mathrm{O}_2 \rightarrow 2 \mathrm{H}_2\mathrm{O}$$?

Accepted Answer

4.0 mol

Question 4

Which of the following statements about balancing chemical equations is correct?

Accepted Answer

Coefficients are changed to balance the equation, but subscripts must never be changed.

Question 5

A sample contains $$1.204 	imes 10$$^{24}$$ molecules of $$\mathrm{H}_2\mathrm{O}$$. How many moles of $$\mathrm{H}_2\mathrm{O}$$ are present?

Accepted Answer

$$2.00$$ mol

Question 6

Given the pie chart (image 2), which best represents the percent composition by mass of carbon, hydrogen, and oxygen in $$\mathrm{C}_{12}\mathrm{H}_{22}\mathrm{O}_{11} ($$sucrose)?

Accepted Answer

Green: Oxygen, Blue: Carbon, Red: Hydrogen

Question 7

What is the molar mass of $$\mathrm{FeSO}_4 \cdot 7\mathrm{H}_2\mathrm{O}$$?

Accepted Answer

$$278.06 g/$$mol

Question 8

A 5.325-g sample of methyl benzoate contains 3.758 g of carbon, 0.316 g of hydrogen, and 1.251 g of oxygen. What is the empirical formula?

Accepted Answer

$$\mathrm{C}_4\mathrm{H}_4\mathrm{O}$$

Question 9

If the actual yield of a reaction is 1.12 g and the theoretical yield is 1.39 g, what is the percent yield?

Accepted Answer

$$80.6\%$$

Question 10

Which of the following is the correct formula weight (in amu) for $$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6$$?

Accepted Answer

$$180.12$$ amu

Question 11

A chemical reaction requires $$5.00$$ mmol NaCl. How many grams should be massed using the laboratory scale? (Molar mass of NaCl = $$58.44 g/$$mol)

Accepted Answer

$$0.292 g$$

Question 12

Which of the following best describes a limiting reactant in a chemical reaction?

Accepted Answer

The reactant that is completely consumed and determines the amount of product formed.

Question 13

How many molecules are in $$0.346$$ mol of $$\mathrm{C}_2\mathrm{H}_4$$?

Accepted Answer

$$2.08 	imes 10$$^{23}$$

Question 14

Which of the following is a decomposition reaction?

Accepted Answer

$$2 \mathrm{KClO}_3 (s) \rightarrow 2 \mathrm{KCl} (s) + 3 \mathrm{O}_2 (g)$$

Question 15

What is the empirical formula for a compound containing 36.8 g nitrogen and 63.25 g oxygen?

Accepted Answer

$$\mathrm{N}_2\mathrm{O}_3$$

Question 16

Which of the following is a correct mole relationship for 1 mole of $$\mathrm{BaCl}_2$$?

Accepted Answer

$$1$$ mole $$\mathrm{BaCl}_2$$ contains $$2 	imes 6.02 	imes 10$$^{23}$$ $$\mathrm{Cl}^-$$ ions.

Question 17

A reaction produces $$6900 ng of$$ $$\mathrm{CO}_2. $$How many kmol of $$\mathrm{CO}_2 is $$this?

Accepted Answer

$$1.6 	imes 10$$^{-10}$$ kmol

Chapter 3 Chemistry

Study Guide - Practice Questions

Study Guide - Flashcards