8.

Question

(01.03 LC)

How is density calculated given mass and volume? (4 points)

Mass divided by volume

Mass multiplied by volume

Sum of volume and mass

Difference of volume and mass
9.
(01.03 LC)

Which of the following is a unit of volume of liquids? (4 points)

Gram

Liters

Liters per cubic gram

Gram per cubic centimeter
10.
(01.03 MC)

Object A has a mass of 12 g and a density of 3 g/cm3. Object B has a mass of 12 g and a density of 5 g/cm3. Which object has a greater volume and by how much? (4 points)

Object A, by 2.6 cubic centimeters

Object A, by 1.6 cubic centimeters

Object B, by 2.6 cubic centimeters

Object B, by 1.6 cubic centimeters
11.
(01.03 MC)

The properties of a cube are listed below:

Density = 40 g/cm3
Length of side = 2 cm

What is the mass of the cube? (4 points)

80 g

160 g

180 g

320 g
12.
(01.04 LC)

What best describes the temperature at which a solid turns into a liquid? (4 points)

Melting point

Boiling point

Electrical conductivity

Thermal conductivity
13.
(01.04 LC)

Which of the following is an intensive property? (4 points)

Mass

Magnetism

Shape

Volume
14.
(01.04 MC)

Read the list of substances.

Wood, Iron, Glass, Aluminum, Paper

Which substances have high thermal conductivity? (4 points)

Iron and Aluminum

Iron and Paper

Wood and Glass

Wood and Paper
15.
(01.04 MC)

Sue classified some substances as shown in the table.

Sue's Table
Good Conductors of Heat Bad Conductors of Heat
Silver Cotton
Copper Wool
Cork Air

Why is Sue's table incorrect? (4 points)

Air is a good conductor of heat.

Wool is a good conductor of heat.

Cork is a bad conductor of heat.

Copper is a bad conductor of heat.
16.
(01.05 MC)

A group of students is investigating whether copper is a better thermal conductor than aluminum. The students take a copper wire and an aluminum wire of the same length and diameter. They put equal lengths of wax on one end of each wire and dip the other ends into a beaker of hot water. The length of wax left on the wires after 10 minutes is shown.

Experimental Observations
Copper Aluminum
Original length of wax 2 cm 2 cm
Length of wax after 10 minutes 0.7 cm 1.2 cm

What was the independent variable in this experiment? (4 points)

Final length of wax

Type of wire used

Original length of wires

Thermal conductivity of wire
17.
(01.04 HC)

The table shows the mass and density of some substances.

Density of Substances
Mass
(g) Density of Iron
(g/cm3) Density of Silver
(g/cm3)
100 7.8 19.3
200 P Q

Part 1: Is the value of Q less than, greater than, or equal to the value of P?
Part 2: Explain your answer for Part 1. (8 points)

18.
(01.05 HC)

Sasha did an experiment to study the solubility of two substances. She poured 100 mL of water at 20 °C into each of two beakers labeled A and B. She put 50 g of Substance A in the beaker labeled A and 50 g of Substance B in the beaker labeled B. The solution in both beakers was stirred for 1 minute. The amount of substance left undissolved in the beakers was weighed. The experiment was repeated for different temperatures of water and the observations were recorded as shown.

Experimental Observations
Substance Mass of Undissolved Substance at Different Temperatures (gram)
20 °C 40 °C 60 °C 80 °C
A 12 11 9 8
B 45 40 34 31

Part 1: Which substance has a higher solubility?
Part 2: Explain your answer for Part 1. (8 points)

Answer 1

Here are the answers to the questions provided:

8. How is density calculated given mass and volume?

• Answer: Mass divided by volume

9. Which of the following is a unit of volume of liquids?

• Answer: Liters

10. Object A has a mass of 12 g and a density of 3 g/cm³. Object B has a mass of 12 g and a density of 5 g/cm³. Which object has a greater volume and by how much?

• Calculation:
  • Volume of Object A = Mass / Density = 12 g / 3 g/cm³ = 4 cm³
  • Volume of Object B = Mass / Density = 12 g / 5 g/cm³ = 2.4 cm³
• Answer: Object A, by 1.6 cubic centimeters

11. The properties of a cube are listed below: Density = 40 g/cm³, Length of side = 2 cm. What is the mass of the cube?

• Calculation:
  • Volume of the cube = side³ = 2 cm × 2 cm × 2 cm = 8 cm³
  • Mass = Density × Volume = 40 g/cm³ × 8 cm³ = 320 g
• Answer: 320 g

12. What best describes the temperature at which a solid turns into a liquid?

• Answer: Melting point

13. Which of the following is an intensive property?

• Answer: Magnetism

14. Which substances have high thermal conductivity?

• Answer: Iron and Aluminum

15. Why is Sue's table incorrect?

• Answer: Cork is a bad conductor of heat.

16. What was the independent variable in this experiment?

• Answer: Type of wire used

17. Part 1: Is the value of Q less than, greater than, or equal to the value of P?

• Answer: Q is less than P.

Part 2: Explain your answer for Part 1.

• Explanation: The density of silver (19.3 g/cm³) is greater than that of iron (7.8 g/cm³). Since mass is given for both substances, the density of a substance is defined as mass per unit volume. A greater density (like that of silver) implies that for the same mass, the volume must be smaller. Therefore, for 200 g of both substances, the volume of silver (which represents Q) would be less than the volume of iron (which represents P).

18. Part 1: Which substance has a higher solubility?

• Answer: Substance A

Part 2: Explain your answer for Part 1.

• Explanation: Higher solubility is indicated by a smaller amount of undissolved substance remaining after mixing with water at different temperatures. In the observations, Substance A shows decreasing undissolved mass from 12 g at 20 °C to 8 g at 80 °C, while Substance B shows a much larger amount of undissolved substance ranging from 45 g at 20 °C to 31 g at 80 °C. Since Substance A has less undissolved mass at every temperature, it has a higher solubility compared to Substance B.