ACT Science Practice Test

Topic 4.1 · Data analysis

As light intensity increased from 100 to 300 µmol/m²/s, the mean height of the plants:

Topic 4.1 · Data analysis

Based on the table, plants grown at 250 µmol/m²/s would most likely have a mean height closest to:

Topic 4.1 · Data analysis

Which light intensity produced plants with a mean of 7 leaves?

Topic 4.1 · Data analysis

Between which two consecutive light intensities did the mean height change the least?

Topic 4.2 · Experiment

What was the independent variable in this experiment?

Topic 4.2 · Experiment

Which of the following was kept the same for all groups?

Topic 4.3 · Experiment

A student claims that raising the light intensity above 400 µmol/m²/s greatly increases plant height. Do the data support this claim?

Topic 4.1 · Data analysis

Passage 2: Students timed 10 complete swings of a pendulum, always released from the same angle.

Experiment 1: The mass was 100 g. The string length was changed.
Length 0.25 m: 10.0 s · Length 0.50 m: 14.2 s · Length 1.00 m: 20.1 s · Length 2.00 m: 28.4 s

Experiment 2: The string length was 1.00 m. The mass was changed.
Mass 50 g: 20.1 s · Mass 100 g: 20.0 s · Mass 200 g: 20.1 s · Mass 400 g: 20.1 s

In Experiment 1, as the length of the string increased, the time for 10 swings:

Topic 4.1 · Data analysis

Passage 2: Students timed 10 complete swings of a pendulum, always released from the same angle.

Experiment 1: The mass was 100 g. The string length was changed.
Length 0.25 m: 10.0 s · Length 0.50 m: 14.2 s · Length 1.00 m: 20.1 s · Length 2.00 m: 28.4 s

Experiment 2: The string length was 1.00 m. The mass was changed.
Mass 50 g: 20.1 s · Mass 100 g: 20.0 s · Mass 200 g: 20.1 s · Mass 400 g: 20.1 s

Based on Experiment 2, the mass of the pendulum has what effect on the time for 10 swings?

Topic 4.1 · Data analysis

Passage 2: Students timed 10 complete swings of a pendulum, always released from the same angle.

Experiment 1: The mass was 100 g. The string length was changed.
Length 0.25 m: 10.0 s · Length 0.50 m: 14.2 s · Length 1.00 m: 20.1 s · Length 2.00 m: 28.4 s

Experiment 2: The string length was 1.00 m. The mass was changed.
Mass 50 g: 20.1 s · Mass 100 g: 20.0 s · Mass 200 g: 20.1 s · Mass 400 g: 20.1 s

In Experiment 1, the time for 10 swings doubled when the length was made 4 times longer (0.25 m to 1.00 m, and 0.50 m to 2.00 m). Based on this pattern, what would the time for 10 swings most likely be for a length of 4.00 m?

Topic 4.2 · Experiment

Passage 2: Students timed 10 complete swings of a pendulum, always released from the same angle.

Experiment 1: The mass was 100 g. The string length was changed.
Length 0.25 m: 10.0 s · Length 0.50 m: 14.2 s · Length 1.00 m: 20.1 s · Length 2.00 m: 28.4 s

Experiment 2: The string length was 1.00 m. The mass was changed.
Mass 50 g: 20.1 s · Mass 100 g: 20.0 s · Mass 200 g: 20.1 s · Mass 400 g: 20.1 s

The students most likely timed 10 swings, rather than 1 swing, in order to:

Topic 4.2 · Experiment

Passage 2: Students timed 10 complete swings of a pendulum, always released from the same angle.

Experiment 1: The mass was 100 g. The string length was changed.
Length 0.25 m: 10.0 s · Length 0.50 m: 14.2 s · Length 1.00 m: 20.1 s · Length 2.00 m: 28.4 s

Experiment 2: The string length was 1.00 m. The mass was changed.
Mass 50 g: 20.1 s · Mass 100 g: 20.0 s · Mass 200 g: 20.1 s · Mass 400 g: 20.1 s

In Experiment 1, which variable was kept constant?

Topic 4.2 · Experiment

Passage 2: Students timed 10 complete swings of a pendulum, always released from the same angle.

Experiment 1: The mass was 100 g. The string length was changed.
Length 0.25 m: 10.0 s · Length 0.50 m: 14.2 s · Length 1.00 m: 20.1 s · Length 2.00 m: 28.4 s

Experiment 2: The string length was 1.00 m. The mass was changed.
Mass 50 g: 20.1 s · Mass 100 g: 20.0 s · Mass 200 g: 20.1 s · Mass 400 g: 20.1 s

The students want to find out whether the release angle affects the time for 10 swings. Which new experiment would best test this?

Topic 4.3 · Experiment

Passage 2: Students timed 10 complete swings of a pendulum, always released from the same angle.

Experiment 1: The mass was 100 g. The string length was changed.
Length 0.25 m: 10.0 s · Length 0.50 m: 14.2 s · Length 1.00 m: 20.1 s · Length 2.00 m: 28.4 s

Experiment 2: The string length was 1.00 m. The mass was changed.
Mass 50 g: 20.1 s · Mass 100 g: 20.0 s · Mass 200 g: 20.1 s · Mass 400 g: 20.1 s

A student predicted that heavier pendulums would swing faster. Do the results of Experiment 2 support this prediction?

Topic 4.1 · Data analysis

According to the table, what is the maximum mass of potassium nitrate that dissolves in 100 g of water at 40°C?

Topic 4.1 · Data analysis

Between which two temperatures in the table does the maximum mass dissolved double?

Topic 4.1 · Data analysis

If 50 g of potassium nitrate is added to 100 g of water at 40°C and stirred, what will happen?

Topic 4.1 · Data analysis

A student dissolves the maximum possible mass of potassium nitrate in 100 g of water at 60°C, then cools the solution to 20°C. About how much solid will form as the solution cools?

Topic 4.2 · Experiment

Which procedure would best find the maximum mass of potassium nitrate that dissolves in 100 g of water at 50°C?

Topic 4.3 · Experiment

Which claim is best supported by the data in the table?

Topic 4.3 · Experiment

Passage 4: A metal spoon and a wooden spoon have been in the same drawer at room temperature (21°C) for several hours. When a student touches them, the metal spoon feels colder. Two students explain why.

Student 1: The metal spoon is actually at a lower temperature than the wooden spoon. Metals are naturally cold materials, and they stay colder than their surroundings.

Student 2: Both spoons are at the same temperature, 21°C. Skin is warmer, about 33°C, so heat flows from the skin into both spoons. Metal conducts heat much better than wood, so it carries heat away from the skin much faster. Losing heat faster is what makes the metal feel colder.

If a thermometer were placed against each spoon, Student 2 would predict that the readings would be:

Topic 4.3 · Experiment

Passage 4: A metal spoon and a wooden spoon have been in the same drawer at room temperature (21°C) for several hours. When a student touches them, the metal spoon feels colder. Two students explain why.

Student 1: The metal spoon is actually at a lower temperature than the wooden spoon. Metals are naturally cold materials, and they stay colder than their surroundings.

Student 2: Both spoons are at the same temperature, 21°C. Skin is warmer, about 33°C, so heat flows from the skin into both spoons. Metal conducts heat much better than wood, so it carries heat away from the skin much faster. Losing heat faster is what makes the metal feel colder.

Which finding would most weaken Student 1's explanation?

Topic 4.3 · Experiment

Passage 4: A metal spoon and a wooden spoon have been in the same drawer at room temperature (21°C) for several hours. When a student touches them, the metal spoon feels colder. Two students explain why.

Student 1: The metal spoon is actually at a lower temperature than the wooden spoon. Metals are naturally cold materials, and they stay colder than their surroundings.

Student 2: Both spoons are at the same temperature, 21°C. Skin is warmer, about 33°C, so heat flows from the skin into both spoons. Metal conducts heat much better than wood, so it carries heat away from the skin much faster. Losing heat faster is what makes the metal feel colder.

Both students agree that:

Topic 4.3 · Experiment

Passage 4: A metal spoon and a wooden spoon have been in the same drawer at room temperature (21°C) for several hours. When a student touches them, the metal spoon feels colder. Two students explain why.

Student 1: The metal spoon is actually at a lower temperature than the wooden spoon. Metals are naturally cold materials, and they stay colder than their surroundings.

Student 2: Both spoons are at the same temperature, 21°C. Skin is warmer, about 33°C, so heat flows from the skin into both spoons. Metal conducts heat much better than wood, so it carries heat away from the skin much faster. Losing heat faster is what makes the metal feel colder.

According to Student 2, when the student touches the spoons, heat flows:

Topic 4.3 · Experiment

Passage 4: A metal spoon and a wooden spoon have been in the same drawer at room temperature (21°C) for several hours. When a student touches them, the metal spoon feels colder. Two students explain why.

Student 1: The metal spoon is actually at a lower temperature than the wooden spoon. Metals are naturally cold materials, and they stay colder than their surroundings.

Student 2: Both spoons are at the same temperature, 21°C. Skin is warmer, about 33°C, so heat flows from the skin into both spoons. Metal conducts heat much better than wood, so it carries heat away from the skin much faster. Losing heat faster is what makes the metal feel colder.

On a very hot day, both spoons are left in the sun until they are at 45°C, warmer than skin. Based on Student 2's explanation, when touched, the metal spoon would most likely feel:

Topic 4.3 · Experiment

Passage 4: A metal spoon and a wooden spoon have been in the same drawer at room temperature (21°C) for several hours. When a student touches them, the metal spoon feels colder. Two students explain why.

Student 1: The metal spoon is actually at a lower temperature than the wooden spoon. Metals are naturally cold materials, and they stay colder than their surroundings.

Student 2: Both spoons are at the same temperature, 21°C. Skin is warmer, about 33°C, so heat flows from the skin into both spoons. Metal conducts heat much better than wood, so it carries heat away from the skin much faster. Losing heat faster is what makes the metal feel colder.

A third material, X, conducts heat even better than the metal. If a spoon made of X were in the same drawer, Student 2 would predict that at room temperature it would feel:

Topic 4.1 · Data analysis

Passage 4: A metal spoon and a wooden spoon have been in the same drawer at room temperature (21°C) for several hours. When a student touches them, the metal spoon feels colder. Two students explain why.

Student 1: The metal spoon is actually at a lower temperature than the wooden spoon. Metals are naturally cold materials, and they stay colder than their surroundings.

Student 2: Both spoons are at the same temperature, 21°C. Skin is warmer, about 33°C, so heat flows from the skin into both spoons. Metal conducts heat much better than wood, so it carries heat away from the skin much faster. Losing heat faster is what makes the metal feel colder.

According to the passage, the temperature of skin is about:

Topic 4.1 · Data analysis

Passage 5 (hypothetical data): A student measured how fast an enzyme broke down hydrogen peroxide by measuring the volume of oxygen gas produced per minute.

Table 1 (all trials at pH 7): Temperature → oxygen produced
15°C: 4 mL/min · 25°C: 9 mL/min · 35°C: 15 mL/min · 45°C: 11 mL/min · 55°C: 3 mL/min

Table 2 (all trials at 35°C): pH → oxygen produced
pH 3: 2 mL/min · pH 5: 9 mL/min · pH 7: 15 mL/min · pH 9: 8 mL/min · pH 11: 1 mL/min

According to Table 1, at which temperature did the enzyme produce oxygen fastest?

Topic 4.1 · Data analysis

Passage 5 (hypothetical data): A student measured how fast an enzyme broke down hydrogen peroxide by measuring the volume of oxygen gas produced per minute.

Table 1 (all trials at pH 7): Temperature → oxygen produced
15°C: 4 mL/min · 25°C: 9 mL/min · 35°C: 15 mL/min · 45°C: 11 mL/min · 55°C: 3 mL/min

Table 2 (all trials at 35°C): pH → oxygen produced
pH 3: 2 mL/min · pH 5: 9 mL/min · pH 7: 15 mL/min · pH 9: 8 mL/min · pH 11: 1 mL/min

According to Table 1, as the temperature increased from 35°C to 55°C, the rate of oxygen production:

Topic 4.1 · Data analysis

Passage 5 (hypothetical data): A student measured how fast an enzyme broke down hydrogen peroxide by measuring the volume of oxygen gas produced per minute.

Table 1 (all trials at pH 7): Temperature → oxygen produced
15°C: 4 mL/min · 25°C: 9 mL/min · 35°C: 15 mL/min · 45°C: 11 mL/min · 55°C: 3 mL/min

Table 2 (all trials at 35°C): pH → oxygen produced
pH 3: 2 mL/min · pH 5: 9 mL/min · pH 7: 15 mL/min · pH 9: 8 mL/min · pH 11: 1 mL/min

The rate at pH 5 (Table 2) was the same as the rate at which temperature in Table 1?

Topic 4.2 · Experiment

Passage 5 (hypothetical data): A student measured how fast an enzyme broke down hydrogen peroxide by measuring the volume of oxygen gas produced per minute.

Table 1 (all trials at pH 7): Temperature → oxygen produced
15°C: 4 mL/min · 25°C: 9 mL/min · 35°C: 15 mL/min · 45°C: 11 mL/min · 55°C: 3 mL/min

Table 2 (all trials at 35°C): pH → oxygen produced
pH 3: 2 mL/min · pH 5: 9 mL/min · pH 7: 15 mL/min · pH 9: 8 mL/min · pH 11: 1 mL/min

In the trials in Table 2, which variable was held constant?

Topic 4.2 · Experiment

Passage 5 (hypothetical data): A student measured how fast an enzyme broke down hydrogen peroxide by measuring the volume of oxygen gas produced per minute.

Table 1 (all trials at pH 7): Temperature → oxygen produced
15°C: 4 mL/min · 25°C: 9 mL/min · 35°C: 15 mL/min · 45°C: 11 mL/min · 55°C: 3 mL/min

Table 2 (all trials at 35°C): pH → oxygen produced
pH 3: 2 mL/min · pH 5: 9 mL/min · pH 7: 15 mL/min · pH 9: 8 mL/min · pH 11: 1 mL/min

What did the student measure to find how fast the enzyme worked?

Topic 4.3 · Experiment

Passage 5 (hypothetical data): A student measured how fast an enzyme broke down hydrogen peroxide by measuring the volume of oxygen gas produced per minute.

Table 1 (all trials at pH 7): Temperature → oxygen produced
15°C: 4 mL/min · 25°C: 9 mL/min · 35°C: 15 mL/min · 45°C: 11 mL/min · 55°C: 3 mL/min

Table 2 (all trials at 35°C): pH → oxygen produced
pH 3: 2 mL/min · pH 5: 9 mL/min · pH 7: 15 mL/min · pH 9: 8 mL/min · pH 11: 1 mL/min

Which conclusion is best supported by both tables?

Topic 4.3 · Experiment

Passage 5 (hypothetical data): A student measured how fast an enzyme broke down hydrogen peroxide by measuring the volume of oxygen gas produced per minute.

Table 1 (all trials at pH 7): Temperature → oxygen produced
15°C: 4 mL/min · 25°C: 9 mL/min · 35°C: 15 mL/min · 45°C: 11 mL/min · 55°C: 3 mL/min

Table 2 (all trials at 35°C): pH → oxygen produced
pH 3: 2 mL/min · pH 5: 9 mL/min · pH 7: 15 mL/min · pH 9: 8 mL/min · pH 11: 1 mL/min

A student claims the enzyme is completely inactive at 15°C. Do the data support this claim?

Topic 4.1 · Data analysis

At what depth was the dissolved oxygen level 4.5 mg/L?

Topic 4.1 · Data analysis

As depth increased, the dissolved oxygen level:

Topic 4.1 · Data analysis

Between which two consecutive depths did the water temperature drop the most?

Topic 4.2 · Experiment

The scientists want to know whether this pattern changes with the seasons. What should they do?

Topic 4.2 · Experiment

In this study, what was the independent variable?

Topic 4.3 · Experiment

A species of fish needs at least 5 mg/L of dissolved oxygen. Based on the data, about how deep could the fish live in this lake on the day measured?