ACT science practice test 76

Directions: Each passage is followed by several questions. After reading a passage, choose the best answer to each question and fill in the corresponding oval on your answer document. You may refer to the passages as often as necessary.

You are NOT permitted to use a calculator on this test.


The main source of the world’s energy for the last century has been fossil fuels. To use fossil fuels, we must be able to locate and recover them at affordable costs, convert them to usable forms, and use them without wasting them or harming the environment.

Experiment 1

Scientists set out to determine the energy potential of various fossil fuels. They burned 1 ton of each of 5 different fuel varieties, and measured the energy produced. Table 1 shows the energy content of various fossil fuels.

Table 1

FuelEnergy Content (Btu/Ton)
Coal25,000,000
Crude oil37,000,000
Gasoline38,000,000
Natural gas47,000,000
Peat3,500,000

Experiment 2

Students completed an experiment to measure the heat energy obtained from natural gas, using water, a Fahrenheit thermometer, and a Bunsen burner (see Figure 1). They filled a beaker with enough water to

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Figure 1

weigh 1 pound (approximately 450 mL). They recorded the temperature of the water, then lit the Bunsen burner and stirred the water continuously. They took several measurements of the water’s temperature, at 5-minute intervals. The results of the experiment are displayed in Table 2.

Table 2

Time (m)Water Temperature (°F)
067°
592°
10117°
15142°

Each type of fossil fuel releases a different amount of energy. This energy is measured in a variety of units. Table 3 provides a conversion chart for energy units.

Table 3

1 Btu =.252 kilocalorie
.000293 kilowatt-hour
1 kilocalorie =3.97 Btus
.0012 kilowatt-hour
1 kilowatt-hour =3,413 Btus
860 kilocalories
1 barrel of oil =5,600,000 Btus
1,410,579 kilocalories
1,640.8 kilowatt-hours

1. According to the results of Experiment 1, which of the following ranks the different types of fossil fuels in order of energy potential, from the most Btus/ton to the least?

F. Peat, coal, crude oil, gasoline, natural gas
G. Natural gas, gasoline, crude oil, coal, peat
H. Gasoline, crude oil, peat, coal, natural gas
J. Natural gas, crude oil, peat, gasoline, coal

2. If 1 Btu is the amount of heat needed to raise the temperature of 1 pound of water 1° Fahrenheit, then how many Btus of natural gas were used during the first 5 minutes of Experiment 2?

A. 92
B. 67
C. 50
D. 25

3. The main purpose of Experiment 2 was to:

F. determine the amount of energy natural gas creates.
G. compare various fossil fuels to see which one produces the most energy.
H. see how long it would take to heat water to 100° F.
J. calculate how much water is necessary to burn 25 Btus of natural gas.

4. If Experiment 2 had been repeated using gasoline to heat the water instead of natural gas, the temperature of the water after 10 minutes would most likely have been closest to which of the following?

A. 40° F
B. 99° F
C. 117° F
D. 180° F

5. According to the data in Table 3, which unit of energy is equivalent to the most Btus?

F. 1 kilowatt-hour
G. 1 kilocalorie
H. 1 barrel of oil
J. 10,000 Btus

6. Based on the results of Experiment 2, if temperature had continued to be measured for 5 more minutes, what would the temperature of the water have most likely been at the next measurement?

A. 85° F
B. 142° F
C. 167° F
D. 200° F

The growth of tumor cells in a culture depends on the amount of nutrients in the culture. Cell production can be determined by counting the number of cells. The effects of various concentrations of glucose and calcium on the growth of three different cell types were tested. Each culture dish began the test with 0.5 million cells, to which was added a solution containing known concentrations of either glucose or calcium. The results after three days are shown in Figures 1 and 2.

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Figure 1

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Figure 2

7. Which of the following variables is represented by the y-axis of the graphs?

F. The number of cells per culture dish after three days
G. The concentration of glucose or calcium present in the solution after three days
H. The number of cells added to each culture dish on the first day
J. The concentration of glucose or calcium present in the solution on the first day

8. According to Figure 1, which cell type(s) produced the largest number of cells with a glucose concentration of 0.4 mg/ml?

A. Cell type A
B. Cell type B
C. Both cell types A and C
D. Both cell types A and B

9. Based on the trends in Figure 2, which of the following statements about cell behavior could you predict if 25 uM of calcium were introduced?

F. Cell type B would produce around 4 million cells.
G. Cell type A would produce around 2 million cells.
H. Cell type C would produce around 2.5 million cells.
J. Cell type C would produce around 0 million cells.

10. Based on the information in Figures 1 and 2, one would predict that the growth of cell type A would be greater than that of cell type C in solutions containing all of the following EXCEPT:

A. 0.2 mg/ml of glucose and 20 uM of calcium.
B. 0.2 mg/ml of glucose and 15 uM of calcium.
C. 0.4 mg/ml of glucose and 20 uM of calcium.
D. 0.6 mg/ml of glucose and 20 uM of calcium.

11. Based on the data in Figures 1 and 2, what can be concluded about the effectiveness of using glucose versus calcium to stimulate cell growth?

F. In all cell types, calcium is more effective than glucose at stimulating cell growth.
G. In all cell types, glucose is more effective than calcium at stimulating cell growth.
H. Calcium is more effective than glucose at stimulating cell growth in cell type B.
J. Glucose is more effective than calcium at stimulating cell growth in cell types A and C.