Q: Which of the following is a correct application of dimensional analysis?

$$\text{Given unit} \times \frac{\text{Find unit}}{\text{Given unit}} = \text{Find unit}$$

Question 1

Which of the following statements best describes a chemical property?

Accepted Answer

Copper reacts with oxygen to form copper oxide.

Question 2

A student measures the mass of a leaf as 0.45 g. Which SI base unit is most appropriate for this measurement?

Accepted Answer

g

Question 3

Which of the following changes is a chemical change?

Accepted Answer

Iron rusting when exposed to air.

Question 4

Express the number 54095 in scientific notation with the correct number of significant figures.

Accepted Answer

$$5.4095 	imes 10^4$

Question 5

A graduated cylinder contains 19.9 mL of water. After adding a piece of galena, the volume increases to 24.5 mL. What is the volume of the galena in liters?

Accepted Answer

$$4.6 	imes 10$$^{-3}$$ L

Question 6

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

Accepted Answer

Mass

Question 7

Convert 21.1°C to Kelvin.

Accepted Answer

$$294.25 K$$

Question 8

A chemist determines the density of a liquid by measuring 30.5 g for a 38.0 mL sample. Which substance is it most likely to be?

Accepted Answer

Ethylene glycol

Question 9

Which of the following is the correct conversion factor to change 15 miles to kilometers, given 1 mile = 1.609 km?

Accepted Answer

$$15 	imes 1.609 km$$

Question 10

A tennis ball with a mass of 58.0 g is served at 128.6 mph ($$57.5 m/s). $$What is its kinetic energy in joules? (Use $$KE = \frac{1}{2}mv^2$ and 1$ kg = 1000$ g)

Accepted Answer

$$95.6 J$$

Question 11

Which of the following statements about significant figures is correct?

Accepted Answer

Zeros after a decimal point and after a nonzero digit are always significant.

Question 12

A pediatrician prescribes 75 mg of amoxicillin per kg of body mass per day, divided into two doses. The child weighs 28 lbs. How many mL of a 125 mg/mL solution should be given per dose? ($$1 kg$$ $$= 2.205$$ lbs)

Accepted Answer

$$3.8 mL$$

Question 13

Which of the following is a correct statement of the law of conservation of mass?

Accepted Answer

The total mass of substances before and after a chemical change is always the same.

Question 14

Which temperature scale is based on the average kinetic energy of particles?

Accepted Answer

Kelvin

Question 15

Which of the following is an example of a quantitative observation?

Accepted Answer

The temperature of the water is $$25.0^{\circ}C.$$

Question 16

A piece of aluminum foil, 22.8 cm on each side, weighs 2.56 g. If the density of aluminum is 2.70 g/mL, what is the thickness of the foil in millimeters?

Accepted Answer

$$0.018 mm$$

Question 17

Which of the following is the correct scientific notation for the speed of light, $$299,792,458 m/s$$, with the correct number of significant figures?

Accepted Answer

$$2.998 	imes 10^8$ m/s

Question 18

Which of the following is a correct application of dimensional analysis?

Accepted Answer

$$	ext{Given unit} 	imes \frac{	ext{Find unit}}{	ext{Given unit}} = 	ext{Find unit}$$

Question 19

Which of the following is a correct rule for rounding significant figures in multiplication and division?

Accepted Answer

The result should have the same number of significant figures as the factor with the fewest significant figures.

Chapter 1: Units of Measurement, Physical and Chemical Change – A Molecular Approach

Guida di studio - Domande di pratica

Study guide - Flashcard