$$D = \frac{50.0\,\text{g}}{25.0\,\text{mL}} = 2.00\,\text{g/mL}$$

$$\frac{2.54\,\text{cm}}{1\,\text{in}}$$

Question 1

Which of the following best describes a compound?

Accepted Answer

A substance that can be decomposed into simpler substances because it contains more than one element.

Question 2

Which physical property is considered intensive?

Accepted Answer

Density

Question 3

A sample of brass is shown in the image. Brass is best classified as:

Accepted Answer

A homogeneous mixture

Question 4

Which of the following is a chemical change?

Accepted Answer

Burning wood

Question 5

According to the Law of Constant Composition, which statement is true about water ($$\mathrm{H_2O}$$)?

Accepted Answer

Every sample of water contains exactly two hydrogen atoms for every one oxygen atom.

Question 6

Which method would best separate a mixture of sand and salt water?

Accepted Answer

Filtration

Question 7

A glass of milk tea is best classified as:

Accepted Answer

A homogeneous mixture

Question 8

Which of the following is NOT a base unit in the SI system?

Accepted Answer

Liter

Question 9

Convert 25°C to Kelvin using the correct formula.

Accepted Answer

$$K = 25 + 273.15 = 298.15$$

Question 10

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

Accepted Answer

Oil and vinegar salad dressing

Question 11

What is the density of a substance if a 50.0 g sample occupies 25.0 mL?

Accepted Answer

$$D = \frac{50.0\,	ext{g}}{25.0\,	ext{mL}} = 2.00\,	ext{g/mL}$$

Question 12

Which of the following is a physical property?

Accepted Answer

Boiling point

Question 13

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

Accepted Answer

Micro

Question 14

A student measures the mass of a sample as 1.0300 × $$10^4 g. $$How many significant figures are in this measurement?

Accepted Answer

Five

Question 15

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 16

Which separation technique would be most appropriate for separating the components of ink?

Accepted Answer

Chromatography

Question 17

Which equation correctly expresses the relationship between kinetic energy, mass, and velocity?

Accepted Answer

$$KE = \frac{1}{2}mv^2$

Question 18

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

Accepted Answer

Toxicity

Question 19

A student needs to convert 5.0 inches to centimeters. Which conversion factor should they use?

Accepted Answer

$$\frac{2.54\,	ext{cm}}{1\,	ext{in}}$$

Question 20

Which of the following statements about molecules and compounds is correct?

Accepted Answer

All compounds are molecules, but not all molecules are compounds.

Chapter 1: Matter, Energy, and Measurement – GOB Chemistry Study Notes

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