$$1 \text{ mg} = 1 \times 10$$^{-3}$$ \text{ g}$$

Question 1

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture in which the composition is uniform throughout, such as air or saltwater.

Question 2

Which of the following is a compound?

Accepted Answer

Table salt (NaCl)

Question 3

Which of the following is the correct balanced chemical equation for the combustion of methane ($$\mathrm{CH_4$}) in $$oxygen?

Accepted Answer

$$\mathrm{CH_4$} + 2\mathrm{O_2$} \rightarrow \mathrm{CO_2$} + 2\mathrm{H_2O}$$

Question 4

A sample of urine has a specific gravity of 1.025 and a volume of 25 mL. What is the mass of the urine sample?

Accepted Answer

26 g

Question 5

Which of the following statements about significant figures is correct?

Accepted Answer

Zeros at the end of a number with a decimal point are significant.

Question 6

Convert 0.0040 L to microliters ($$\muL).$$

Accepted Answer

4,000 $$\muL$$

Question 7

Which of the following is a physical change?

Accepted Answer

Melting ice to form liquid water

Question 8

A doctor prescribes 7.5 mg/kg of acetaminophen for a child who weighs 42 lbs. How many mg should be given per dose? (1 kg = 2.2 lbs)

Accepted Answer

140 mg

Question 9

Which of the following is the correct formula for density?

Accepted Answer

$$d = \frac{m}{V}$$

Question 10

Which of the following is NOT a property of gases?

Accepted Answer

Definite shape

Question 11

Which of the following is a micronutrient essential for human health?

Accepted Answer

Iron

Question 12

What is the correct conversion factor to convert from milligrams (mg) to grams (g)?

Accepted Answer

$$1 	ext{ mg} = 1 	imes 10$$^{-3}$$ 	ext{ g}$$

Question 13

Which of the following best describes the difference between accuracy and precision?

Accepted Answer

Accuracy is how close measurements are to the true value; precision is how close measurements are to each other.

Question 14

Which of the following is the correct scientific notation for 0.00055?

Accepted Answer

$$5.5 	imes 10$$^{-5}$$

Question 15

A solution is prepared by dissolving 10 g of salt in 90 g of water. What is the percent by mass of salt in the solution?

Accepted Answer

11%

Question 16

Which of the following is a heterogeneous mixture?

Accepted Answer

Vegetable soup

Question 17

Convert 5 mL to deciliters (dL).

Accepted Answer

0.05 dL

Question 18

Which of the following is the correct relationship between Celsius and Kelvin?

Accepted Answer

$$K = ^\circ C + 273$$

Question 19

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

Accepted Answer

Burning charcoal

Question 20

How many significant figures are in the measurement 0.0030?

Accepted Answer

2

Chapter 1: Chemistry Basics—Matter and Measurement (GOB Chemistry Study Notes)

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