Question 1

A patient is prescribed 250 mg of a medication. The available tablets are 100 mg each. How many tablets should the patient take per dose?

Accepted Answer

2.5 tablets

Question 2

A sample of $$^{99m}\mathrm{Tc}$$ used in medical imaging has a half-life of 6 hours. If you start with 80 mg, how much remains after 18 hours?

Accepted Answer

$$10\ \mathrm{mg}$$

Question 3

Which ion is most likely formed by sulfur according to the octet rule and its position on the periodic table?

Accepted Answer

$$\mathrm{S}^{2-}$$

Question 4

What is the correct formula and name for the compound formed between magnesium and chlorine?

Accepted Answer

$$\mathrm{MgCl}_2$$, magnesium chloride

Question 5

Which of the following statements best distinguishes ionic from covalent compounds?

Accepted Answer

Ionic compounds consist of metals and nonmetals and involve electron transfer; covalent compounds consist of nonmetals and involve electron sharing.

Question 6

What is the correct name for $$\mathrm{N}_2\mathrm{O}_5$$?

Accepted Answer

Dinitrogen pentoxide

Question 7

Given the electronegativity values: H (2.1), Cl (3.0), and O (3.5), which bond is the most polar?

Accepted Answer

H–Cl

Question 8

Which molecule is nonpolar?

Accepted Answer

$$\mathrm{CO}_2$$

Question 9

Which type of intermolecular force is primarily responsible for the high boiling point of water?

Accepted Answer

Hydrogen bonding

Question 10

How many molecules are in 0.25 mol of glucose ($$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6$$)? ($$N_A = 6.02 	imes 10$$^{23}$$)

Accepted Answer

$$1.51 	imes 10$$^{24}$$

Question 11

What is the molar mass of $$\mathrm{Ca(OH)_2}$$?

Accepted Answer

$$74\ \mathrm{g/mol}$$

Question 12

If 2.0 mol of $$\mathrm{H}_2$$ react with excess $$\mathrm{O}_2 to $$form water, how many grams of $$\mathrm{H}_2\mathrm{O}$$ are produced? ($$\mathrm{H}_2 + 0.5\mathrm{O}_2 \rightarrow \mathrm{H}_2\mathrm{O}$$, $$M_{\mathrm{H}_2$$\mathrm{O}} = 18\ \mathrm{g/mol}$$)

Accepted Answer

$$36\ \mathrm{g}$$

Question 13

For the reaction $$\mathrm{N}_2 + 3\mathrm{H}_2 \rightleftharpoons 2\mathrm{NH}_3$$, which is the correct expression for the equilibrium constant $$K$$?

Accepted Answer

$$K = \dfrac{[\mathrm{NH}_3]^2}{[\mathrm{N}_2][\mathrm{H}_2]^3}$$

Question 14

A reaction at equilibrium is disturbed by adding more reactant. According to Le Chatelier’s principle, what will happen?

Accepted Answer

The system will shift to produce more products.

Question 15

A gas occupies 4.0 L at 1.0 atm and 300 K. What will be its volume at 2.0 atm and 300 K? (Assume ideal gas behavior.)

Accepted Answer

2.0 L

Question 16

What is the molarity of a solution containing 5.0 g of NaCl ($$M_{\mathrm{NaCl}} = 58.5\ \mathrm{g/mol}) $$dissolved in 250 mL of solution?

Accepted Answer

$$0.34\ \mathrm{M}$$

Question 17

Which of the following is a conjugate acid-base pair?

Accepted Answer

$$\mathrm{NH}_4^+$$ / $$\mathrm{NH}_3$$

Question 18

What is the pH of a solution with $$[\mathrm{H}^+] = 1 	imes 10$$^{-5}$$\ \mathrm{M}$$?

Accepted Answer

5

Question 19

During a titration, 25.0 mL of 0.200 M HCl is neutralized by 0.100 M NaOH. What volume of NaOH is required?

Accepted Answer

50.0 mL

Comprehensive Study Notes for GOB Chemistry: Chapters 2–12

Guida di studio - Domande di pratica

Study guide - Flashcard