Question 1

Which of the following best describes the difference between a reactant and a product in a chemical reaction?

Accepted Answer

A reactant is a substance present at the start of a reaction, while a product is a substance formed as a result of the reaction.

Question 2

What is the volume occupied by 1 mole of an ideal gas at standard temperature and pressure (STP)?

Accepted Answer

$$22.4\ 	ext{L}$$

Question 3

Balance the following chemical equation: $$\mathrm{Cr} + \mathrm{O}_2 \rightarrow \mathrm{Cr}_2\mathrm{O}_3$$

Accepted Answer

$$4\mathrm{Cr} + 3\mathrm{O}_2 \rightarrow 2\mathrm{Cr}_2\mathrm{O}_3$$

Question 4

Which of the following is the correct balanced equation for photosynthesis?

Accepted Answer

$$6\mathrm{CO}_2 + 6\mathrm{H}_2\mathrm{O} \rightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2$$

Question 5

Given the reaction $$2\mathrm{NO} + \mathrm{O}_2 \rightarrow 2\mathrm{NO}_2$$, what is the molar ratio of $$\mathrm{NO} to$$ $$\mathrm{NO}_2$$?

Accepted Answer

$$1:1$$

Question 6

If 0.105 mol of propane ($$\mathrm{C}_3\mathrm{H}_8) is $$burned in excess oxygen, how many moles of oxygen are consumed? ($$\mathrm{C}_3\mathrm{H}_8 + 5\mathrm{O}_2 \rightarrow 3\mathrm{CO}_2 + 4\mathrm{H}_2\mathrm{O})$$

Accepted Answer

$$0.525\ 	ext{mol}$$

Question 7

Calculate the mass of $$\mathrm{O}_2$$ needed to react with $$5.00\ \mathrm{g} of $$carbon to form $$\mathrm{CO}_2$$. ($$\mathrm{C} + \mathrm{O}_2 \rightarrow \mathrm{CO}_2)$$

Accepted Answer

$$13.3\ \mathrm{g}$$

Question 8

Which of the following best defines a solution in chemistry?

Accepted Answer

A homogeneous mixture where the major component is the solvent and the minor component(s) are solutes.

Question 9

What is the molarity (M) of a solution containing $$0.30\ 	ext{mol} of $$solute in $$0.60\ 	ext{L} of $$solution?

Accepted Answer

$$0.50\ 	ext{M}$$

Question 10

How many grams of NaCl are required to prepare $$0.750\ 	ext{L} of a$$ $$0.15\ 	ext{M}$$ NaCl solution? ($$	ext{Molar mass of NaCl} = 58.44\ 	ext{g/mol})$$

Accepted Answer

$$6.6\ 	ext{g}$$

Question 11

A pint of beer (500 mL) contains 25 mL alcohol. What is the percent alcohol by volume (ABV)?

Accepted Answer

$$5\%$$

Question 12

What is the percent sugar by mass in a hummingbird food mixture containing $$20\ 	ext{g}$$ sugar and $$80\ 	ext{g}$$ water?

Accepted Answer

$$20\%$$

Question 13

Which of the following is the correct sequence of steps for a stoichiometric calculation?

Accepted Answer

Write and balance the equation, determine molar masses, convert moles of given to moles of desired, convert moles to grams.

Question 14

Which of the following statements about molarity is correct?

Accepted Answer

Molarity is defined as moles of solute per liter of solution.

Question 15

You are asked to prepare 430 g of an aqueous solution that is 4.85% by mass NaNO$$_3. $$How many grams of NaNO$$_3$$ are needed?

Accepted Answer

$$20.9\ 	ext{g}$$

Question 16

Which of the following best explains why water is often called the 'universal solvent'?

Accepted Answer

Water can dissolve a wide variety of substances due to its polarity.

Question 17

A solution is described as 'dilute.' What does this mean about the solution?

Accepted Answer

It contains a relatively small amount of solute compared to solvent.

Question 18

Which of the following is a correct statement about balancing chemical equations?

Accepted Answer

The number of atoms of each element must be the same on both sides of the equation.

Lecture 14

Guida di studio - Domande di pratica

Study guide - Flashcard