Question 1

Which of the following compounds is most likely to be an ionic compound based on its formula and properties?

Accepted Answer

NaCl (sodium chloride), a solid with high melting point

Question 2

Which of the following is the correct classification for O$$_2 ($$oxygen gas)?

Accepted Answer

Molecular element

Question 3

What is the correct name for FeCl$$_3$$?

Accepted Answer

Iron(III) chloride

Question 4

Which formula corresponds to the name ammonium sulfate?

Accepted Answer

(NH$$_4$$)$$_2SO$_4$$

Question 5

What is the correct formula for dinitrogen pentoxide?

Accepted Answer

N$$_2O$_5$$

Question 6

Calculate the molar mass of calcium nitrate, Ca(NO$$_3$$)$$_2.$$

Accepted Answer

$$164.10\ \mathrm{g/mol}$$

Question 7

How many molecules are present in 18.0 g of water (H$$_2O$$)?$ (Molar mass = 18.0 g/mol)

Accepted Answer

$$6.02 	imes 10$$^{23}$$

Question 8

A sample contains 40.0 g of NaOH (molar mass = 40.0 g/mol). What is the mass percent of Na in NaOH?

Accepted Answer

$$60.0\%$$

Question 9

Which statement best describes the difference between empirical and molecular formulas?

Accepted Answer

The empirical formula shows the simplest whole-number ratio of atoms, while the molecular formula shows the actual number of atoms in a molecule.

Question 10

A compound contains 52.2% C, 13.0% H, and 34.8% O by mass. What is its empirical formula?

Accepted Answer

C$$_2H$_6O$$

Question 11

A hydrocarbon is combusted and produces 4.40 g CO$$_2$$ and 1.80 g H$$_2O. $$What is the empirical formula of the hydrocarbon?

Accepted Answer

CH$$_2$$

Question 12

Balance the following equation: $$\mathrm{C_3H_8 + O_2$ \rightarrow CO_2$ + H_2O}$$

Accepted Answer

$$\mathrm{C_3H_8 + 5O_2 \rightarrow 3CO_2 + 4H_2O}$$

Question 13

If 2.0 mol of H$$_2$$ react with 1.0 mol of O$$_2 to $$form water, what is the limiting reactant?

Accepted Answer

O$$_2$$

Question 14

A reaction has a theoretical yield of 10.0 g but produces only 7.5 g of product. What is the percent yield?

Accepted Answer

$$75\%$$

Question 15

Which is the correct molecular equation for the reaction of sodium sulfate and barium chloride in aqueous solution?

Accepted Answer

$$\mathrm{Na_2SO_4(aq) + $$BaCl_2$$(aq) \rightarrow 2NaCl(aq) + $$BaSO_4$$(s)}$$

Question 16

What is the molarity of a solution prepared by dissolving 5.00 g of NaCl (molar mass = 58.44 g/mol) in enough water to make 250.0 mL of solution?

Accepted Answer

$$0.342\ \mathrm{M}$$

Question 17

Which of the following compounds is a strong electrolyte and soluble in water?

Accepted Answer

NaNO$$_3$$

Question 18

Write the net ionic equation for the reaction between HCl(aq) and NaOH(aq).

Accepted Answer

$$\mathrm{H^+(aq) + OH^-(aq) \rightarrow H_2O(l)}$$

Question 19

What is the oxidation state of sulfur in SO$$_2$$?

Accepted Answer

$$+4$$

Question 20

Which of the following reactions is a redox reaction, and what is the oxidizing agent?

$$\mathrm{Zn(s) + $$CuSO_4$$(aq) \rightarrow $$ZnSO_4$$(aq) + Cu(s)}$$

Accepted Answer

Yes, Cu$$^{2+} is $$the oxidizing agent

General Chemistry: Compounds, Chemical Formulas, and Reactions

Study Guide - Practice Questions