Question 1

A sample contains 12.0 grams of carbon (C). How many moles of carbon are present in the sample? (Atomic mass of C = 12.0 g/mol)

Accepted Answer

$$1.0$$ mol$

Question 2

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

Accepted Answer

NaCl (sodium chloride)

Question 3

What is the molar mass of Ca(NO$$_3$$)$$_2$$?

Accepted Answer

$$164 g/$$mol$

Question 4

A reaction produces 15.0 g of product, but the theoretical yield is 20.0 g. What is the percent yield?

Accepted Answer

$$75\%$$

Question 5

Which of the following is a single displacement reaction?

Accepted Answer

Zn + 2HCl → ZnCl$$_2 + H$_2$$

Question 6

Which of the following acids is a strong acid?

Accepted Answer

HCl (hydrochloric acid)

Question 7

What is the correct electron configuration for a neutral atom of sodium (Na)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^1$$

Question 8

Which intermolecular force is dominant in CH$$_3OH ($$methanol)?

Accepted Answer

Hydrogen bonding

Question 9

A solution is prepared by diluting 50.0 mL of 6.0 M HCl to a final volume of 300.0 mL. What is the final concentration?

Accepted Answer

$$1.0 M$

Question 10

Which of the following molecules is nonpolar?

Accepted Answer

CO$$_2$$

Question 11

What is the oxidation state of chromium in Cr$$_2O$_3$$?

Accepted Answer

$$+3$$

Question 12

Which of the following is the correct name for Fe$$_2(SO$_4$$)$$_3$$?

Accepted Answer

Iron(III) sulfate

Question 13

Which of the following statements about isotopes is TRUE?

Accepted Answer

Isotopes have different numbers of neutrons.

Question 14

Which of the following best explains why water has a higher boiling point than methane?

Accepted Answer

Water forms hydrogen bonds, while methane does not.

Question 15

What is the pH of a solution with $$[H^+] = 1 	imes 10$$^{-4}$$ M?

Accepted Answer

$$4$$

Question 16

Which of the following is a decomposition reaction?

Accepted Answer

2KClO$$_3$$ → 2KCl + 3O$$_2$$

Question 17

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

Accepted Answer

Ca$$_3(PO$_4$$)$$_2$$

Question 18

A sample contains 0.50 moles of NaCl. How many formula units of NaCl are present? ($$N_A = 6.02 	imes 10$$^{23}$$ mol$$^{-1}$$)

Accepted Answer

$$3.01 	imes 10$$^{23}$$

Question 19

Which of the following best describes the shape of a methane (CH$$_4) $$molecule according to VSEPR theory?

Accepted Answer

Tetrahedral

Question 20

Which of the following is a correct statement about the periodic table?

Accepted Answer

Metalloids are located along the staircase line.

Comprehensive Study Guide for GOB Chemistry: Key Concepts and Calculations

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