1.

Question

(01.01 LC)

What is true about a scientific idea? (4 points)

It is biased in its results.

It asks about an opinion.

It asks about a moral value.

It can be observed and tested.
2.
(01.01 LC)

What is a scientific method? (4 points)

A method that is biased

A method based on moral beliefs

A system which constitutes a single step

A system for conducting a scientific investigation
3.
(01.01 LC)

Which of the following is usually done first in the scientific method of investigation? (4 points)

Do research on a particular topic

Ask a question based on an observation

Construct a hypothesis to be tested

Test with an experiment
4.
(01.01 MC)

Melanie wants to observe the effect of two new fertilizers on the growth of plants. Three identical plants having a height of 15 cm were used for the experiment. No fertilizer was added to the first plant, 100 g of Fertilizer A was added to the second plant, and 100 g of Fertilizer B was added to the third plant. All other growing conditions of the plants were kept constant. Which step of the scientific method did Melanie do here? (4 points)

Drawing a conclusion

Testing with an experiment

Doing background research

Analyzing experimental data
5.
(01.02 LC)

What does the mass of an object depend on? (4 points)

Force of gravity

Temperature of the object

Time taken for an event to occur

Amount of matter that makes up the object
6.
(01.02 MC)

Two descriptions about physical quantities are given below:

Quantity A: It is unaffected by the location of an object in space.
Quantity B: It can be measured in kilograms.

What quantities are these most likely describing? (4 points)

Both Quantity A and Quantity B are mass.

Both Quantity A and Quantity B are weight.

Quantity A is weight and Quantity B is mass.

Quantity A is mass and Quantity B is weight.
7.
(01.02 MC)

The gravitational strength on Earth is greater than the gravitational strength on Mars. Which statement is correct? (4 points)

The weight of an object will be greater on Earth than Mars.

The weight of an object will be greater on Mars than Earth.

The mass of an object will be greater on Earth than Mars.

The mass of an object will be greater on Mars than Earth.
8.
(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 your questions:

1. What is true about a scientific idea?

   • It can be observed and tested.

2. What is a scientific method?

   • A system for conducting a scientific investigation.

3. Which of the following is usually done first in the scientific method of investigation?

   • Ask a question based on an observation.

4. Which step of the scientific method did Melanie do here?

   • Testing with an experiment.

5. What does the mass of an object depend on?

   • Amount of matter that makes up the object.

6. What quantities are these most likely describing?

   • Quantity A is mass and Quantity B is weight.

7. Which statement is correct?

   • The weight of an object will be greater on Earth than Mars.

8. How is density calculated given mass and volume?

   • Mass divided by volume.

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

   • Liters.

10. Which object has a greater volume and by how much?

    • Object A, by 1.6 cubic centimeters. (Volume of Object A = Mass/Density = 12g / 3g/cm³ = 4 cm³; Volume of Object B = 12g / 5g/cm³ = 2.4 cm³; 4 cm³ - 2.4 cm³ = 1.6 cm³.)

11. What is the mass of the cube?

    • 160 g. (Volume = \( \text{Length}^3 = 2cm \times 2cm \times 2cm = 8cm³ \); Mass = Density x Volume = 40g/cm³ x 8cm³ = 320g.)

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

    • Melting point.

13. Which of the following is an intensive property?

    • Magnetism.

14. Which substances have high thermal conductivity?

    • Iron and Aluminum.

15. Why is Sue's table incorrect?

    • Air is a good conductor of heat. (The statement is misleading; air is generally a poor conductor, but wax, if present, acts as an insulator in the context of heat transfer in this experimental setup.)

16. What was the independent variable in this experiment?

    • Type of wire used.

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

    • The value of Q is greater than the value of P. Part 2: Explain your answer for Part 1.
    • Since density is calculated as mass divided by volume (Density = Mass/Volume), and mass is constant for both substances (200 g), if iron has a higher density than silver (7.8 g/cm³ for iron versus 19.3 g/cm³ for silver), then the volume occupied by 200 g of silver (which is less dense) will be less than that occupied by iron. Thus, Q, representing the density of silver at 200 g, must be less than P, which is the density of iron at the same mass.

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

    • Substance A has a higher solubility. Part 2: Explain your answer for Part 1.
    • Substance A shows a significant decrease in the amount of undissolved substance as the temperature increases (from 12 g at 20 °C to 8 g at 80 °C), indicating that it dissolves more readily in water as temperature increases. In contrast, Substance B, while it does show a decrease in undissolved mass, still leaves a higher amount undissolved compared to Substance A across all temperatures measured, demonstrating that Substance A has a higher overall solubility.