Question 1

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more different kinds of elements in a fixed ratio.

Question 2

Which of the following is an example of an intensive property?

Accepted Answer

Density

Question 3

A student separates a mixture of sand and salt by adding water, filtering, and then evaporating the water. Which separation techniques are used in this process?

Accepted Answer

Filtration and evaporation

Question 4

Which of the following equations correctly converts a temperature of 25 °C to Kelvin?

Accepted Answer

$$K = 25 + 273.15$$

Question 5

A sample of ethanol has a mass of 46.0 g and a volume of 58.0 mL. What is its density?

Accepted Answer

$$D = \frac{46.0}{58.0} = 0.793 \ \mathrm{g/mL}$$

Question 6

Which of the following is a chemical property?

Accepted Answer

Flammability

Question 7

Which of the following best describes a heterogeneous mixture?

Accepted Answer

A mixture with variable composition throughout

Question 8

A measurement is recorded as 0.00450 g. How many significant figures does this value have?

Accepted Answer

3

Question 9

Which of the following is the correct SI base unit for the amount of substance?

Accepted Answer

Mole (mol)

Question 10

A student measures the boiling point of water three times and gets 101.2°C, 101.3°C, and 101.1°C. The accepted value is 100.0°C. Which statement is correct?

Accepted Answer

The measurements are precise but not accurate.

Question 11

Which of the following is a derived SI unit?

Accepted Answer

Liter (L)

Question 12

Which of the following is the correct conversion factor to change centimeters to inches?

Accepted Answer

$$\frac{1\ \mathrm{in}}{2.54\ \mathrm{cm}}$$

Question 13

A solution is prepared by dissolving 10.0 g of NaCl in 90.0 g of water. Which term best describes this mixture?

Accepted Answer

Homogeneous mixture (solution)

Question 14

Which of the following is an example of a physical change?

Accepted Answer

Melting of ice

Question 15

Which prefix represents $$10^{-6} in $$the metric system?

Accepted Answer

Micro-

Question 16

A graduated cylinder contains 25.0 mL of water. A metal object is added, and the water level rises to 32.5 mL. If the mass of the object is 60.0 g, what is its density?

Accepted Answer

$$D = \frac{60.0}{7.5} = 8.00\ \mathrm{g/mL}$$

Question 17

Which of the following statements about the law of constant composition is correct?

Accepted Answer

The relative number of atoms of each element in a compound is always the same.

Question 18

Which of the following is NOT a base SI unit?

Accepted Answer

Liter (L)

Question 19

A sample is described as having a mass of 10.0 g, a volume of 5.0 mL, and a boiling point of 78.4°C. Which of these is an extensive property?

Accepted Answer

Mass

Question 20

Which of the following best describes the process of distillation?

Accepted Answer

Separation based on differences in boiling points

Introduction to Chemistry: Matter and Measurement

Guida di studio - Domande di pratica

Study guide - Flashcard