Q: A box has dimensions: length = 3.12 cm, width = 3.1 cm, height = 7.62 cm. What is the volume with the correct number of significant figures?

$$3.12 \times 3.1 \times 7.62 = 74 cm$^3$$

Question 1

Which of the following best describes a compound, according to the classification of matter chart?

Accepted Answer

A substance that cannot be separated by physical means but can be decomposed by chemical processes.

Question 2

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

Accepted Answer

Density

Question 3

A sample of seawater is 3.5% NaCl by mass. How many grams of NaCl can be extracted from 2.0 kg of seawater?

Accepted Answer

$$0.035 	imes 2000 = 70 g$$

Question 4

Which of the following statements about significant figures is correct?

Accepted Answer

Zeroes between nonzero digits are significant.

Question 5

A student measures the mass of a sample three times and gets values very close to each other, but far from the true value. This is an example of:

Accepted Answer

Low accuracy, high precision

Question 6

Which of the following is a chemical change?

Accepted Answer

Burning of gasoline

Question 7

What is the density of a solution if 15.0 g of isopropanol is isolated from a 25.0 mL sample, assuming the mass of the rest of the solution is negligible?

Accepted Answer

$$\frac{15.0}{25.0} = 0.60 g/mL$$

Question 8

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

Accepted Answer

Salt water

Question 9

Convert $$25 ^\circ C to $$Kelvin.

Accepted Answer

$$25 + 273.15 = 298.15 K$$

Question 10

How many significant figures are in the number 0.000500?

Accepted Answer

3

Question 11

Which of the following best describes the difference between mass and weight?

Accepted Answer

Mass is the amount of matter, weight is the force due to gravity.

Question 12

A box has dimensions: length = 3.12 cm, width = 3.1 cm, height = 7.62 cm. What is the volume with the correct number of significant figures?

Accepted Answer

$$3.12 	imes 3.1 	imes 7.62 = 74 cm$^3$$

Question 13

Which of the following is NOT a pure substance?

Accepted Answer

Air

Question 14

Which of the following is an example of a systematic error?

Accepted Answer

A balance that is not zeroed before use

Question 15

Which of the following is true about mixtures?

Accepted Answer

They can be separated by physical means.

Question 16

A student records the following measurements for the mass of a sample: 2.51 g, 2.53 g, 2.52 g. The true mass is 2.80 g. Which statement is correct?

Accepted Answer

The measurements are precise but not accurate.

Question 17

Which of the following is a molecule of an element?

Accepted Answer

O$$_2$$

Question 18

Which of the following is a correct rule for rounding off numbers?

Accepted Answer

If the digit you are rounding is greater than 5, increase the final digit by one.

Question 19

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

Accepted Answer

Granite

Question 20

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

Accepted Answer

Evaporation of alcohol

Matter: Its Properties and Measurement (Chapter 1) - General Chemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard