Q: Which of the following is an exact number?

$$12\ \text{in} = 1\ \text{ft}$$

Q: Which of the following is the correct formula for density?

$$\text{Density} = \dfrac{\text{Mass}}{\text{Volume}}$$

Q: A proton has a radius of $$1.0 \times 10$$^{-13}$$ cm and a mass of 1.7$$ \times $$10^{-24} g. $$What is its density? (Volume of a sphere: $$V = \dfrac{4}{3}\pi r^3$)

$$4.1 \times 10$$^{12}$$\ \text{g/cm}^3$$

Q: Convert 1898 mg to kg. ($$1\ \text{g} = 1000\ \text{mg}$$, $$1\ \text{kg} = 1000\ \text{g})$$

$$1.898 \times 10$$^{-3}$$\ \text{kg}$$

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

$$\text{Given unit} \times \dfrac{\text{desired unit}}{\text{given unit}} = \text{desired unit}$$

Question 1

Which of the following best describes a chemical property?

Accepted Answer

Iron rusts when exposed to oxygen.

Question 2

A sample of copper is heated from room temperature to 95°C. What happens to its density?

Accepted Answer

The sample expands.

Question 3

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

Accepted Answer

Wet sand

Question 4

Which of the following is an exact number?

Accepted Answer

$$12\ 	ext{in} = 1\ 	ext{ft}$$

Question 5

A European car gets 17 km/L. What is its gas mileage in miles per gallon? ($$1\ 	ext{km} = 0.6214\ 	ext{mi}$$, $$1\ 	ext{gal} = 3.785\ 	ext{L})$$

Accepted Answer

28.0 mi/gal

Question 6

Which of the following statements about energy is TRUE?

Accepted Answer

Energy is always conserved in a physical or chemical change.

Question 7

Which of the following is the correct formula for density?

Accepted Answer

$$	ext{Density} = \dfrac{	ext{Mass}}{	ext{Volume}}$$

Question 8

A measurement is recorded as 0.004560 g. How many significant figures does this value have?

Accepted Answer

4

Question 9

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

Accepted Answer

Accuracy is how close a measurement is to the true value; precision is how reproducible measurements are.

Question 10

Which of the following is a physical change?

Accepted Answer

Boiling water to produce steam

Question 11

A proton has a radius of $$1.0 	imes 10$$^{-13}$$ cm and a mass of 1.7$$ 	imes $$10^{-24} g. $$What is its density? (Volume of a sphere: $$V = \dfrac{4}{3}\pi r^3$)

Accepted Answer

$$4.1 	imes 10$$^{12}$$\ 	ext{g/cm}^3$$

Question 12

Which of the following is a derived SI unit?

Accepted Answer

Joule (J)

Question 13

Which separation technique would be best to separate a mixture of sand and water?

Accepted Answer

Filtration

Question 14

Which of the following is an intensive property?

Accepted Answer

Density

Question 15

Convert 1898 mg to kg. ($$1\ 	ext{g} = 1000\ 	ext{mg}$$, $$1\ 	ext{kg} = 1000\ 	ext{g})$$

Accepted Answer

$$1.898 	imes 10$$^{-3}$$\ 	ext{kg}$$

Question 16

Which of the following is a pure substance?

Accepted Answer

Helium

Question 17

Which temperature scale has the same degree size as the Kelvin scale?

Accepted Answer

Celsius

Question 18

A student adds $$1239.3 + 9.73 + 3.42. $$What is the answer rounded to the correct number of significant figures?

Accepted Answer

$$1252.5$$

Question 19

Which of the following best explains why ice floats on water?

Accepted Answer

Ice is less dense than liquid water.

Question 20

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

Accepted Answer

$$	ext{Given unit} 	imes \dfrac{	ext{desired unit}}{	ext{given unit}} = 	ext{desired unit}$$

CHEM 131 Chapter 1: Matter, Measurement, and Problem Solving

Guida di studio - Domande di pratica

Study guide - Flashcard