Q: Which of the following best describes the definition of molarity ($$M$$)?

$$M = \dfrac{\text{amount of solute (in mol)}}{\text{volume of solution (in L)}}$$

Question 1

A solution is prepared by dissolving 25.5 g of KBr in enough water to make 1.75 L of solution. What is the molarity of the solution? (Molar mass of KBr = 119.00 g/mol)

Accepted Answer

$$0.122\,\mathrm{M}$$

Question 2

Which of the following best describes the definition of molarity ($$M$$)?

Accepted Answer

$$M = \dfrac{	ext{amount of solute (in mol)}}{	ext{volume of solution (in L)}}$$

Question 3

How many liters of a $$0.125\,\mathrm{M}$$ NaOH solution are required to contain $$0.255$$ mol NaOH?

Accepted Answer

$$2.04\,\mathrm{L}$$

Question 4

A student wants to prepare $$250.0\,\mathrm{mL} of a$$ $$1.50\,\mathrm{M}$$ KBr solution. What mass of KBr (in grams) is required? (Molar mass of KBr = $$119.00\,\mathrm{g/mol})$$

Accepted Answer

$$44.6\,\mathrm{g}$$

Question 5

What volume (in L) should you dilute $$0.200\,\mathrm{L} of a$$ $$15.0\,\mathrm{M}$$ NaOH solution to obtain a $$3.00\,\mathrm{M}$$ NaOH solution?

Accepted Answer

$$1.00\,\mathrm{L}$$

Question 6

Which of the following compounds is insoluble in water?

Accepted Answer

PbCl$$_2$$

Question 7

What is the balanced molecular equation for the precipitation reaction when solutions of potassium carbonate and nickel(II) chloride are mixed?

Accepted Answer

$$K_2CO_3(aq) + $$NiCl_2$$(aq) \rightarrow $$NiCO_3$$(s) + 2KCl(aq)$$

Question 8

Which of the following is the net ionic equation for the reaction between aqueous acetic acid ($$HC_2H_3O_2) $$and potassium hydroxide ($$KOH$$)?

Accepted Answer

$$HC_2H_3O_2(aq) + OH^-(aq) \rightarrow H_2O(l) + C_2H_3O_2^-(aq)$$

Question 9

A titration of $$10.00\,\mathrm{mL} of $$HCl solution of unknown concentration requires $$12.54\,\mathrm{mL} of$$ $$0.100\,\mathrm{M}$$ NaOH solution to reach the equivalence point. What is the concentration of the unknown HCl solution?

Accepted Answer

$$0.125\,\mathrm{M}$$

Question 10

Which of the following is the correct molecular equation for the gas-evolution reaction when aqueous nitric acid reacts with sodium carbonate?

Accepted Answer

$$2HNO_3(aq) + Na_2CO_3(aq) \rightarrow H_2O(l) + CO_2$(g) + 2NaNO_3(aq)$$

Question 11

Assign the oxidation state to sulfur in $$SO_4$$^{2-}$$.

Accepted Answer

$$+6$$

Question 12

In the reaction $$Mg(s) + 2H_2O(l) \rightarrow Mg(OH)_2(aq) + H_2$(g)$$, which element is oxidized and which is reduced?

Accepted Answer

Mg is oxidized, H is reduced

Question 13

Which of the following reactions is a redox reaction? Identify the oxidizing agent.

Accepted Answer

$$2Mg(s) + O_2$(g) \rightarrow 2MgO(s)$$; oxidizing agent: $$O_2$$

Question 14

Predict whether the following redox reaction is spontaneous: $$Fe(s) + Pb$$^{2+}$$(aq) \rightarrow Fe$$^{2+}$$(aq) + Pb(s)$$

Accepted Answer

Spontaneous

Question 15

Which of the following is the correct net ionic equation for the neutralization of HCl with NaOH?

Accepted Answer

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

Question 16

A $$0.150\,\mathrm{M}$$ KCl solution is to react completely with $$0.150\,\mathrm{L} of$$ $$0.175\,\mathrm{M} Pb(NO$_3$$)$$_2$$ solution according to the equation $$2KCl(aq) + Pb(NO_3$)_2(aq) \rightarrow $$PbCl_2$$(s) + 2KNO_3(aq). $$What volume (in L) of KCl solution is required?

Accepted Answer

$$0.350\,\mathrm{L}$$

Question 17

Which of the following compounds is always soluble in water?

Accepted Answer

Ca(NO$$_3$$)$$_2$$

Chapter 5: Introduction to Solutions and Aqueous Reactions – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard