$$3.4 \times 10$$^{-4}$$\ \mathrm{m}$$

$$\text{Density} = \dfrac{\text{mass}}{\text{volume}}$$

Question 1

Which of the following best describes the change occurring in the first image (boiling water on a stove)?

Accepted Answer

A physical change, because the chemical composition of water remains the same.

Question 2

In the second image (dissolving a solid in water), what type of change is occurring and why?

Accepted Answer

A physical change, because the solid can be recovered by evaporation.

Question 3

Which of the following best describes the process shown in the third image (chopping vegetables)?

Accepted Answer

A physical change, because only the size and shape are changed.

Question 4

The fourth image shows sugar and an enzyme producing alcohol and carbon dioxide. What type of change is this?

Accepted Answer

A chemical change, because new substances are formed.

Question 5

Which of the following best describes the mixture shown in the tenth image (oil and water in a beaker)?

Accepted Answer

A heterogeneous mixture, because there are distinct layers.

Question 6

Which of the following is the correct scientific notation for the number shown in the eleventh image (215 = $$2.15 × 10^2$$)?

Accepted Answer

$$2.15 	imes 10^2$

Question 7

Which of the following statements about significant figures is correct?

Accepted Answer

Zeroes at the end of a number and after the decimal point are significant.

Question 8

A sample of water has a mass of 18.0 g and a volume of 18.0 mL. What is its density?

Accepted Answer

$$1.00\ \mathrm{g/mL}$$

Question 9

Convert 0.00034 meters to scientific notation.

Accepted Answer

$$3.4 	imes 10$$^{-4}$$\ \mathrm{m}$$

Question 10

Which of the following is a derived SI unit?

Accepted Answer

Gram per cubic centimeter $$(g/cm^3)$$

Question 11

A patient’s temperature is 104°F. What is this temperature in Celsius? (Use $$^\circ C = (F-32)/1.8)$$

Accepted Answer

$$40^\circ C$$

Question 12

Which of the following is an example of a homogeneous mixture?

Accepted Answer

Salt dissolved in water

Question 13

Which of the following is a compound?

Accepted Answer

Sodium chloride (NaCl)

Question 14

How many significant figures are in the measurement 0.00450 mL?

Accepted Answer

3

Question 15

Which of the following is the correct conversion factor for converting from deciliters (dL) to milliliters (mL)?

Accepted Answer

$$1\ \mathrm{dL} = 100\ \mathrm{mL}$$

Question 16

A child is 21.5 inches long at birth. How long is this in centimeters? (1 inch = 2.54 cm)

Accepted Answer

$$54.6\ \mathrm{cm}$$

Question 17

Which of the following is the correct formula for density?

Accepted Answer

$$	ext{Density} = \dfrac{	ext{mass}}{	ext{volume}}$$

Question 18

Which of the following is NOT a physical quantity?

Accepted Answer

Color

Question 19

Which of the following is the correct SI unit for temperature?

Accepted Answer

Kelvin (K)

Question 20

A solution contains 0.0026 g of phosphorus. Express this value in milligrams using scientific notation.

Accepted Answer

$$2.6 	imes 10$$^{-1}$$\ \mathrm{mg}$$

Chapter 1: Chemistry, Matter, and Measurement – Structured Study Notes

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