Q: What is the frequency (in Hz) of light with a wavelength of $$500\ \mathrm{nm}$$? (Speed of light $$c = 3.00 \times 10^8$\ \mathrm{m/s})$$

$$6.00 \times 10$$^{14}$$\ \mathrm{Hz}$$

Question 1

A compound is found to contain 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is the empirical formula of this compound?

Accepted Answer

$$\mathrm{CH}_2\mathrm{O}$$

Question 2

Which of the following reactions is a precipitation reaction?

Accepted Answer

$$\mathrm{AgNO}_3(aq) + \mathrm{NaCl}(aq) \rightarrow \mathrm{AgCl}(s) + \mathrm{NaNO}_3(aq)$$

Question 3

Which of the following is the correct net ionic equation for the reaction between aqueous solutions of sodium sulfate and barium chloride?

Accepted Answer

$$\mathrm{Ba}^{2+}(aq) + \mathrm{SO}_4$$^{2-}$$(aq) \rightarrow \mathrm{BaSO}_4(s)$$

Question 4

Which of the following acids is correctly named and matched with its formula?

Accepted Answer

Sulfuric acid, $$\mathrm{H}_2\mathrm{SO}_4$$

Question 5

In the reaction $$2\mathrm{Fe}_2\mathrm{O}_3(s) + 3\mathrm{C}(s) \rightarrow 4\mathrm{Fe}(s) + 3\mathrm{CO}_2(g)$$, what is the oxidation number of iron in $$\mathrm{Fe}_2\mathrm{O}_3$$ and which element is reduced?

Accepted Answer

Iron: $$+3$$; Iron is reduced

Question 6

Which of the following best describes the role of hydrogen peroxide ($$\mathrm{H}_2\mathrm{O}_2) $$when it decomposes into water and oxygen?

Accepted Answer

Hydrogen peroxide acts as both an oxidizing and reducing agent (disproportionation).

Question 7

Given the activity series: $$\mathrm{Mg} \u003e \mathrm{Zn} \u003e \mathrm{Cu}$$, which of the following reactions will occur spontaneously?

Accepted Answer

$$\mathrm{Mg}(s) + \mathrm{CuSO}_4(aq) \rightarrow \mathrm{MgSO}_4(aq) + \mathrm{Cu}(s)$$

Question 8

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

Accepted Answer

$$0.342\ \mathrm{M}$$

Question 9

What is the frequency (in Hz) of light with a wavelength of $$500\ \mathrm{nm}$$? (Speed of light $$c = 3.00 	imes 10^8$\ \mathrm{m/s})$$

Accepted Answer

$$6.00 	imes 10$$^{14}$$\ \mathrm{Hz}$$

Question 10

Which of the following sets of quantum numbers is NOT allowed for an electron in an atom?

Accepted Answer

$$n=2,\ l=2,\ m_l=0,\ m_s=+\frac{1}{2}$$

Question 11

A 25.0 mL sample of $$0.200\ \mathrm{M}$$ HCl is titrated with $$0.100\ \mathrm{M}$$ NaOH. What volume of NaOH (in mL) is required to reach the equivalence point?

Accepted Answer

$$50.0\ \mathrm{mL}$$

Question 12

Which of the following is the correct molecular formula for a compound with empirical formula $$\mathrm{CH}_2\mathrm{O}$$ and a molar mass of $$180\ \mathrm{g/mol}$$?

Accepted Answer

$$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6$$

Question 13

Which of the following is a redox reaction?

Accepted Answer

$$2\mathrm{Na}(s) + 2\mathrm{H}_2\mathrm{O}(l) \rightarrow 2\mathrm{NaOH}(aq) + \mathrm{H}_2(g)$$

Question 14

Which of the following best describes the reducing agent in the reaction $$\mathrm{Zn}(s) + \mathrm{CuSO}_4(aq) \rightarrow \mathrm{ZnSO}_4(aq) + \mathrm{Cu}(s)$$?

Accepted Answer

Zinc, because it loses electrons and is oxidized.

Question 15

A student mixes $$50.0\ \mathrm{mL} of$$ $$0.400\ \mathrm{M}$$ NaOH with $$150.0\ \mathrm{mL} of $$water. What is the final concentration of NaOH after dilution?

Accepted Answer

$$0.100\ \mathrm{M}$$

Question 16

Which of the following is the correct set of quantum numbers for the last electron added to a potassium atom ($$Z=19) in $$its ground state?

Accepted Answer

$$n=4,\ l=0,\ m_l=0,\ m_s=+\frac{1}{2}$$

Question 17

Which of the following is the correct ionic equation for the neutralization of hydrochloric acid with sodium hydroxide?

Accepted Answer

$$\mathrm{H}^+(aq) + \mathrm{OH}^-(aq) \rightarrow \mathrm{H}_2\mathrm{O}(l)$$

Question 18

A sample of light has a frequency of $$4.00 	imes 10$$^{14}$$\ \mathrm{Hz}. $$What is its wavelength in nanometers? (Speed of light $$c = 3.00 	imes 10^8$\ \mathrm{m/s})$$

Accepted Answer

$$750\ \mathrm{nm}$$

Exam 2 Concept Guide: General Chemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard