ACT Science

Test Taking Tips

ACT Science Section: 3 formats

• Data Representation (30-40%) (*This is what we will look at today!)

• Research Summaries (45-55%)• Conflicting Viewpoints (15-20%)

Data Representation (30-40%)

Uses Tables & Graphs.

Measures skills such as:• graph reading• interpretation of scatterplots• interpretation of information presented in

tables.

Data Representation

• Tip #1 - Look at the correct table or graph!

• Tip #2 – Read all of the labels & identify the info that you need.

Data representation

• Tip #3 – Pay attention to “increase” & “decrease”. Sometimes the table will show an increase but the question will ask for the interval of decrease.

• Tip #4 – Watch out for unit changes.

REFER to ACT Science Passage III handout to answer the following 4

questions…

OR

go to http://www.actstudent.org/sampletest/science/

AND click on Passage 3

• In general, the results of Study 1 suggest that peony seeds that are placed in a petri dish containing damp paper are most likely to germinate when they are maintained at which of the following temperatures?

A. 13°CB. 18°CC. 23°CD. 28°C

ANSWER B.

• B is the best answer. In Study 1 more seeds germinated when they were maintained at a germination temperature of 18°C than when they were maintained at any of the other 3 germination temperatures. So the seeds are more likely to germinate when they are maintained at 18°C than when they are maintained at 13°C, 23°C, or 28°C.

In Study 2, at the storage temperature of 5°C, as germination temperature increased from 13°C to 28°C, the number of seeds that germinated:

• 1. A. decreased only.• 2. B. increased only.• 3. C. decreased, then increased.• 4. D. increased, then decreased

ANSWER D.

• D is the best answer. In Study 2, 4 germination temperatures were used: 13°C, 18°C, 23°C, and 28°C. The numbers of seeds that germinated at these 4 temperatures were 16, 23, 21, and 1, respectively. So, as germination temperature increased from 13°C to 28°C, the number of seeds that germinated initially increased (from 16 to 23) and then decreased (from 23 to 21 and from 21 to 1).

A student stored 100 peony seeds at a constant temperature for 10 weeks. The student then divided the seeds into 4 sets and maintained them as described in Study 2. The results were as follows:

These seeds most likely had a storage temperature of: • A. 0°C. B. 5°C.• C. 10°C. D. 15°C.

ANSWER C.

• C is the best answer. Look at the results from Study 2, at a storage temperature of 10°C and a germination temperature of 13°C, 0 seeds germinated. In Study 2, at a storage temperature of 10°C and a germination temperature of 18°C, 6 seeds germinated. In Study 2, at a storage temperature of 10°C and a germination temperature of 23°C, 4 seeds germinated. In Study 2, at a storage temperature of 10°C and a germination temperature of 28°C, 0 seeds germinated. These results closely match the results given in the question.

The experimental designs of Study 2 and Study 1 differed in that in Study 2: F. storage temperature was held constant.G. storage time was held constant.H. germination temperature was varied.J. germination time was varied.

ANSWER G.

• G is the best answer. In Study 1, 5 storages periods were used: 0, 4, 6, 8, and 10 weeks. In Study 2, 1 storage period was used: 10 weeks. So, in Study 2, storage time was held constant. In Study 1, storage time was varied.

REFER to ACT Science Passage IV handout to answer the following

questions…

OR

go to http://www.actstudent.org/sampletest/science/

AND click on Passage 4

• According to Study 2, the thermal conductivity of rock salt measured at a temperature of 500°C would be closest to which of the following values? – A. 1.0 W/m°C– B. 2.0 W/m°C– C. 3.5 W/m°C– D. 4.0 W/m°C

ANSWER is B.

• B is the best answer. In Study 2, as temperature increased from 0°C to 400°C, thermal conductivity of rock salt decreased from about 6.1 W/m°C to about 2.2 W/m°C. In addition, the rate of the decrease slowed as temperature increased. For example, as temperature increased from 300°C to 400°C, thermal conductivity decreased by about 0.4 W/m°C (from about 2.6 W/m°C to about 2.2 W/m°C). Based on this trend, thermal conductivity at 500°C would be about 0.2 W/m°C less than the thermal conductivity at 400°C (2.2 W/m°C). So, the best estimate is 2.0 W/m°C.

• Welded tuff (another rock type) has a thermal conductivity of 1.8 W/m°C at 25°C. If measurements of the temperature of this rock type adjacent to SF canisters were taken as in Study 1, the recorded temperature would be closest to: – A. 100°C.– B. 110°C.– C. 120°C.– D. 130°C.

ANSWER D.

• D is the best answer. Table 1 shows how the recorded rock temperature varied with thermal conductivity. Granite has a thermal conductivity of 2.80 W/m°C and it had a temperature of 121°C. Shale has a thermal conductivity of 1.57 W/m°C and it had a temperature of 146°C. Since welded tuff has a thermal conductivity (1.8 W/m°C) between the thermal conductivities of granite and shale, welded tuff will have a temperature between the temperatures observed for granite and shale: 121°C and 146°C. 130°C falls between these 2 values.

• According to the results of Study 1, which of the following best describes the relationship between thermal conductivity and rock temperature? As thermal conductivity increases, the rock temperature recorded adjacent to buried SF canisters: – F. decreases only.– G. increases only.– H. increases, then decreases.– J. remains the same.

ANSWER is F.

• F is the best answer. Table 1 shows how the recorded rock temperature varied with thermal conductivity. Higher thermal conductivities are associated with lower rock temperatures. For example, the rock type with the lowest thermal conductivity (basalt) had the highest rock temperature, and the rock type with the highest thermal conductivity (rock salt) had the lowest rock temperature. So as thermal conductivity increases, rock temperature decreases only.

• Which of the following procedures, in addition to Studies 1, 2, and 3, would best test whether the amount of heat generated by SF is related to the mass of the SF ? F. Following the design of Study 1 but using concrete canisters containing 0.4 metric tons of SFG. Following the design of Study 1 but using stainless steel canisters containing 0.8 metric tons of SFH. Following the design of Study 2 but determining the thermal conductivities of twice as much of each rock typeJ. Following the design of Study 3 but determining the rock temperatures 0.5 km from the sites of SF burial

ANSWER is G.

• G is the best answer. To determine whether the amount of heat generated by SF is related to the mass of the SF, the amount of heat generated by SF should be determined as the mass of the SF is varied. To do this, Study 1 should be repeated with a different mass of SF. In Study 1, 0.4 metric tons of SF were tested, so using 0.8 metric tons of SF would provide a comparison to determine how the mass of the SF affects the amount of heat generated by the SF.

• SOURCE: http://www.actstudent.org/sampletest/science/

• Go to this website for more practice!!!!