Q: A compound contains 40.0 g of carbon and 6.7 g of hydrogen. What is the percent composition of hydrogen in the compound?

$$\frac{6.7}{40.0 + 6.7} \times 100 = 14.3\%$$

Q: Which of the following is the correct relationship between pH and pOH in aqueous solution?

$$\text{pH} + \text{pOH} = 14$$

Question 1

Which quantum number determines the energy level of an electron in an atom?

Accepted Answer

$$n ($$principal quantum number)

Question 2

Which of the following elements has the highest ionization energy?

Accepted Answer

Chlorine (Cl)

Question 3

A compound contains 40.0 g of carbon and 6.7 g of hydrogen. What is the percent composition of hydrogen in the compound?

Accepted Answer

$$\frac{6.7}{40.0 + 6.7} 	imes 100 = 14.3\%$$

Question 4

Which molecular geometry is expected for a molecule with 4 bonding pairs and 1 lone pair on the central atom?

Accepted Answer

Seesaw

Question 5

Which of the following statements about strong acids is correct?

Accepted Answer

Strong acids completely dissociate in water

Question 6

A sample of gas at STP occupies 22.4 L. How many moles of gas are present?

Accepted Answer

1 mole

Question 7

Which of the following is the correct expression for the equilibrium constant $$K$$ for the reaction $$aA + bB \rightleftharpoons cC + dD$$?

Accepted Answer

$$K = \frac{[C]^c [D]^d}{[A]^a [B]^b}$$

Question 8

Which of the following best describes the role of a catalyst in a chemical reaction?

Accepted Answer

It lowers the activation energy ($$E_a)$$

Question 9

Which of the following is always soluble in water according to the solubility rules?

Accepted Answer

Potassium nitrate (KNO$$_3)$$

Question 10

A reaction has $$\Delta H \u003c 0. $$What does this indicate about the reaction?

Accepted Answer

The reaction is exothermic and releases heat

Question 11

Which of the following is the correct formula for calculating the pH of a solution?

Accepted Answer

$$	ext{pH} = -\log[H^+]$$

Question 12

Which statement correctly describes oxidation in electrochemistry?

Accepted Answer

Oxidation is the loss of electrons

Question 13

If the rate law for a reaction is $$	ext{Rate} = k[A]^2[B]$$, what is the overall order of the reaction?

Accepted Answer

Third order

Question 14

Which of the following is a property of ionic compounds?

Accepted Answer

They are formed between metals and nonmetals

Question 15

Which of the following is the correct relationship between pH and pOH in aqueous solution?

Accepted Answer

$$	ext{pH} + 	ext{pOH} = 14$$

Question 16

A solution is prepared by dissolving 0.5 mol of NaCl in enough water to make 1.0 L of solution. What is the molarity (M) of the solution?

Accepted Answer

$$0.5\ 	ext{M}$$

Question 17

Which of the following best describes a double replacement reaction?

Accepted Answer

Two compounds exchange ions to form two new compounds

Question 18

What is the cell potential ($$E^\circ_{	ext{cell}}) $$for a galvanic cell if $$E^\circ_{	ext{cathode}} = 0.80\ 	ext{V}$$ and $$E^\circ_{	ext{anode}} = -0.76\ 	ext{V}$$?

Accepted Answer

$$E^\circ_{	ext{cell}} = 0.80 - (-0.76) = 1.56\ 	ext{V}$$

Question 19

Which of the following best explains why atomic radius decreases across a period?

Accepted Answer

Effective nuclear charge increases, pulling electrons closer

Question 20

A balloon contains 2.0 L of gas at 1.0 atm. If the pressure increases to 2.0 atm at constant temperature, what will be the new volume?

Accepted Answer

$$1.0\ 	ext{L}$$

General Chemistry: Comprehensive Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard