Q: How many atoms are in $$2.00\ \mathrm{mol} of $$sodium ($$\mathrm{Na}$$)? (Avogadro's number $$= 6.022 \times 10$$^{23}$$\ \mathrm{atoms/mol})$$

$$1.20 \times 10$$^{24}$$\ \mathrm{atoms}$$

Question 1

A sample contains 18.0 grams of water ($$\mathrm{H_2O}). $$How many moles of water are present in the sample? (Molar mass of $$\mathrm{H_2O} is$$ $$18.0\ \mathrm{g/mol})$$

Accepted Answer

$$1.0\ \mathrm{mol}$$

Question 2

How many atoms are in $$2.00\ \mathrm{mol} of $$sodium ($$\mathrm{Na}$$)? (Avogadro's number $$= 6.022 	imes 10$$^{23}$$\ \mathrm{atoms/mol})$$

Accepted Answer

$$1.20 	imes 10$$^{24}$$\ \mathrm{atoms}$$

Question 3

Which of the following best describes a redox reaction?

Accepted Answer

A reaction in which electrons are transferred between species

Question 4

What is the oxidation number of sulfur in $$\mathrm{SO_2$}$$?

Accepted Answer

$$+4$$

Question 5

Balance the following equation: $$\mathrm{C_2H_6} + \mathrm{O_2$} \rightarrow \mathrm{CO_2$} + \mathrm{H_2O}$$

Accepted Answer

$$2\ \mathrm{C_2H_6} + 7\ \mathrm{O_2$} \rightarrow 4\ \mathrm{CO_2$} + 6\ \mathrm{H_2O}$$

Question 6

Which of the following compounds is most likely to be insoluble in water?

Accepted Answer

$$\mathrm{AgCl}$$

Question 7

A solution is made by dissolving $$5.85\ \mathrm{g} of $$sodium chloride ($$\mathrm{NaCl}) in $$water to make $$0.100\ \mathrm{L} of $$solution. What is the molarity of the solution? (Molar mass of $$\mathrm{NaCl} is$$ $$58.5\ \mathrm{g/mol})$$

Accepted Answer

$$1.00\ \mathrm{M}$$

Question 8

Which of the following is the correct formula for calcium phosphate?

Accepted Answer

$$\mathrm{Ca_3$(PO_4$)_2}$$

Question 9

Which of the following best describes a double replacement reaction?

Accepted Answer

Two compounds exchange ions to form two new compounds

Question 10

What is the limiting reactant when $$2.0\ \mathrm{mol} of$$ $$\mathrm{H_2$}$$ reacts with $$1.0\ \mathrm{mol} of$$ $$\mathrm{O_2$} to $$form water according to $$2\ \mathrm{H_2$} + \mathrm{O_2$} \rightarrow 2\ \mathrm{H_2O}$$?

Accepted Answer

$$\mathrm{H_2$}$$

Question 11

Which of the following is a decomposition reaction?

Accepted Answer

$$2\ \mathrm{$$KClO_3$$} \rightarrow 2\ \mathrm{KCl} + 3\ \mathrm{O_2$}$$

Question 12

Which of the following is the correct name for $$\mathrm{H_2SO_4}$$?

Accepted Answer

Sulfuric acid

Question 13

What is the empirical formula of a compound that contains $$40.0\%$$ carbon, $$6.7\%$$ hydrogen, and $$53.3\%$$ oxygen by mass?

Accepted Answer

$$\mathrm{CH_2O}$$

Question 14

Which of the following is a strong electrolyte in aqueous solution?

Accepted Answer

$$\mathrm{NaCl}$$

Question 15

Which of the following ions is polyatomic?

Accepted Answer

$$\mathrm{NO_3$^-}$$

Question 16

Which of the following is a type II metal ion?

Accepted Answer

$$\mathrm{Fe$$^{2+}$$}$$

Question 17

What is the formula mass of $$\mathrm{$$CaCO_3$$}$$? (Atomic masses: $$\mathrm{Ca} = 40.1$$, $$\mathrm{C} = 12.0$$, $$\mathrm{O} = 16.0)$$

Accepted Answer

$$100.1$$

Question 18

Which of the following best describes what is reduced in a redox reaction?

Accepted Answer

The species that gains electrons

Question 19

Which of the following is the correct formula for the compound formed between aluminum and sulfate?

Accepted Answer

$$\mathrm{Al_2$(SO_4$)_3}$$

Introduction to Chemistry: Study Guide for Chapters 5–8 (Atoms, Moles, Chemical Reactions, and Redox)

Guida di studio - Domande di pratica

Study guide - Flashcard