C. KOHNWATERFORD UNION HIGH SCHOOL

ACT – Science Reasoning

Quick Test

A triangle’s sides are doubled from 2 to 4.By how much does the total area of the

triangle increase by? A. 50% B. 100% C. 300% D. 400%

“total new area”?

Introduction

Personal Introduction Science background Educational background Why me?

This slideshow (available online)

Materials – we’ll primarily use the ACT Victory Book The others you can use at home on your own to prepare.

The test – next pages

The Test

Goals – 1. Become familiar with many of the concepts that are

tested on the official test 2. Be able to target the item-types that you are best

equipped to answer. i.e. there are always the same “kinds” of questions on the

ACT – know your strengths and your areas for improvement.

The Test

Item-TypesScience Reasoning has three categories:

1. Comprehension Making sense of a passage; understanding the “gist” of

something. 2. Analysis

Finding the trends and relationships in data & information.

3. Application Applying old information in a new way

The Test

Item type examples Comprehension: find values on a chart or table;

perform calculations with certain values; read a graph and ID the labeling; ID elements of experimental design; ID explicit arguments

Analysis: ID trends & explain data; draw conclusions from data; form hypotheses based on data; evaluate experimental methods; extrapolate data from an experiment; predict results under different conditions; analyze what would support or refute an argument.

Application: Use the results of an experiment to understand a new situation; reevaluate an experiment in light of new information; predict how an author would respond to new info

FYI, Tips, and Strategies

1. The ACT does not test scientific knowledge! It’s not what you know…it’s how you use your knowledge See pg 220 (do on your own later)

2. Do the easiest questions first. Let your subconscious do the hard stuff (really!). Skim each passage and determine what it’s asking. Every passage will emphasize either Data Representation,

Research Summaries, or Conflicting Viewpoints The subject matter of the passage will give you an idea of how

difficult it is. Determine if it’s a cakewalk or a gauntlet. Choose accordingly.

Save the hardest for last, and start with the easiest.

Strategies

3. Worry about the questions after you’ve started reading (unlike the reading portion).

4. Underline (or bracket) key words and phrases. For example, “increase in area” is very different from

“total new area”! 5. Focus only on what is there – ignore

previous experience and do not infer or assume. Pay special attention to asterisks and given facts. Do not dwell on technical or difficult material – refer to

the passage as often as necessary. Not sure what something is? It may not matter!

Strategies

6. Pay special attention to differences: indentify how each table is different from other tables. Explain how different methods are distinct from each other. Determine how viewpoints diverge.

7. Avoid assumptions: look for assumptions that are not supported by the data (i.e. it has to be this way, even though the data never referred to it).

8. Focus on trends: how does the independent variable affect the dependent variable? Directly? Inversely? Exponentially?

Strategies

9. Do not move on until you’ve finished all the questions in a passage. This will save time and eliminate personal mistakes.

10. Answer the question that is being asked. In other words, do not give the answer that they are not seeking. Pay special attention to the wording in order to avoid missing the questions you could have otherwise gotten correct.

11. Find the answer before looking at the choices. Compare your answer with those given.

Strategies

12. Take notes! Jot down ideas in the margins or summarize the author’s main points. Do not focus on subjective viewpoints – focus on the objective data, trends, and assumptions.

Strategy Summary

1. It’s not what you know…it’s how you use your knowledge.

2. Do the easiest questions first.3. Worry about the questions after you’ve started reading

(?). 4. Underline (or bracket) key words and phrases. 5. Focus only on what is there.6. Pay special attention to differences.7. Avoid assumptions.8. Focus on trends.9. Do not move on until you’ve finished all the questions in

a passage.10. Answer the question that is being asked. 11. Find the answer before looking at the choices.12. Take notes.

Passage I (p. 327)

The kinetic energy of an object with mass m (measured in grams) after a fall from height h (measured in centimeters) was recorded for different heights. A graph was made representing the kinetic energy vs. height.

Passage I, Question 1.

1. If the kinetic energy is given in units of g * cm2 / s2 , what units must the slope have?A. g * cm/sB. g * cm/s2

C. g * cm/gD. s2 / (g * cm)

Passage I, Question 2.

2. It is discovered that if we redo the experiment with an object with twice the mass, the kinetic energy obtained for every height is doubled. The slope of the new set of experiments can be obtained by doing what to the old slope?

A. Multiplying by 2B. Dividing by 2C. SquaringD. Taking the square

root.

Passage I, Question 3.

3. What would be the kinetic energy in g * cm2 / s2

of an object of mass m if t were dropped from a height of 4.5 cm?

A. 4.5B. 9.0C. 45D. 90

Passage I, Question 1.

1. If the kinetic energy is given in units of g * cm2 / s2 , what units must the slope have?A. g * cm/sB. g * cm/s2

C. g * cm/gD. s2 / (g * cm)

What is the formula for slope? Rise over Run (y/x). Determine the units for rise (y axis) and divide them by the run (x axis).

Passage I, Question 2.

2. It is discovered that if we redo the experiment with an object with twice the mass, the kinetic energy obtained for every height is doubled. The slope of the new set of experiments can be obtained by doing what to the old slope?

F. Multiplying by 2G. Dividing by 2H. SquaringI. Taking the square

root.

Think about the phrases:- “kinetic energy is doubled” = y axis-Height is not mentioned; x axis does not change- slope = rise/run, or y/x

Passage I, Question 3.

3. What would be the kinetic energy in g * cm2 / s2

of an object of mass m if t were dropped from a height of 4.5 cm?

A. 4.5B. 9.0C. 45D. 90

At 1 cm, our KE was 10. At 2 cm, our KE was 20. Seems like a 1:10 correlation, and that our x is directly proportional to our y (not exponential or inversely related) So, if at 1 cm we have

a y value of 10, and at 2 cm, we have a y value of 20, our 10x = y. If x =4.5, then y = 45.So, it should be C.

THINK: Why might they choose 90 as the other alternative? Reviewing the other answers may reveal the pitfalls.

Data Representation Strategies

Graphs will always be to scaleYou can save considerable time by reviewing

the graphs and charts visually without necessarily reading the actual numbers E.g. in most cases, a taller column will correspond to a

greater amount than a shorter column. This may be all you need to know!

Graph Reading Strategies

1. Summarize the main point of the graph or chart – read the main title or description.

2. Preview the graph or chart – read the description of the axes and note the units used (as well as their scale!)

3. Quickly summarize and preview – the items will lead back to the actual relevant information.

Tables (see p. 328)

Questions about tables may refer to specific rows or columns, and they may ask about the general trends or applications of all the material in a table.

The first step of understanding a table is to understand the nature of the experiment, how it is set up, and how the data is arranged (p. 328) Notice that this deals primarily with sexual maturity The variables are temperature and food, and temp is kept

constant for three trials of different food intakes. You should realize that we could compare food intake at

two different temps to determine their individual result while also considering the table as a whole

The second step is to recognize trends (next slide)

Trends

Typical questions ask for predictions of what will happen if particular variables are changed in the experiment or for comparison of the results of two or more trials. Notice on p. 328 that an increase in temp and an

increase in food cause a decrease in birthing age. Automatically, you should begin to ask why. Better nutrition means more energy for sexual

maturation We don’t know that this is the cause, but based on the

data, it could make sense. Be careful not to make unsupported assumptions, however!

Drawing Conclusions

The third step is to draw conclusions.Avoid conclusions that are not supported by the

data!For #9 on p.328, the only things that we know

are what impacts temperature and food intake have on birthing age. THAT’S IT! We know nothing about the offspring It might be reasonable to assume that an infant will

benefit from extra nutrition, but we have no evidence of this!

This leaves C and D; C best correlates to the data.

Examples of Data Representation on the ACT

Select a conclusion that can be supported by fig 1Determine what the slope of a given line represents in

fig 2Predict the results given an assumption or a new

situation.Select a statement that is best supported by the data

represented in graph 1Determine the results based on the difference of time

or location. Determine the relationship between two variables.Determine which conclusion is NOT consistent with the

information given in graph 2Select an explanation for a given outcomeIdentify the LEAST significant assumption made when

determining a particular outcome.

For Next Time

Do page 328-330Take it as if you’re taking the ACT – do NOT

lie to yourself! Getting some wrong now will help to correct your

thinking for when you take the test for real.

Data Representation

P. 329 shows an inverse relationship between two variables in the top half.

As the average blood pressure decreases the distance from the left ventricle of the heart increases.

The bottom half shows a direct relationship between two variables.

As the Total Surface Area increases, the distance from the left ventricle increases.

Data Rep, p. 606

Notice that the * indicates that pulse is the difference between Systole and Diastole. If it is starred, it will most likely be asked in the questions. We can only see this difference between the aorta and the

capillaries.** indicates that blood velocity is the lowest in the

capillaries. A glimpse at the graph shows that the surface area is greatest in the capillaries. Scientific minds would automatically consider the possibility that these two concepts are related.

It is also clear that blood pressure is not related to surface area or velocity. Blood pressure seems to be a function of distance from the left ventricle.

Research Summary Review and Strategies

Research summary items Understanding Design of Experiment items require an

understanding of the information about the design and implementation of the various experiments and results. E.g. a typical item might ask what the metal hoop

represents (the supporting bone for the eardrum). Predicting Results: these ask for conjectures based on

data. It is important not only to understand the experiment but also any special results.

Evaluating Data – analysis of data to support or refute hypotheses.

Research Summary Item Examples

ID the difference in the experimental design of the two experiments

Predict an outcome based on the results of experiment 2

Predict the outcome of experiment 1 when one of the variables is altered.

ID an assumption of Exp’t 2 based on the results.ID a conclusion supported by the given results of

Exp’t 1. Select an experiment that should be conducted in

order to test another hypothesis.ID a hypothesis that was investigated in Exp’t 1.

Research Summary Strategies

1. ID the controls and the variables. For a given experiment, the controls are always

constant – only the tested factor varies. Always keep in mind the purpose of a control!

2. Anticipate how to alter experimental variables to support alternative hypotheses. Predict the results of these new experiments

3. For depicted data trends, determine any proportional or inverse relationships between the experimental factors and the results.

Strategies

4. If an assumption is faulty because it is not supported by given information, the experiment may fail to prove the hypothesis and conclusions based on the assumption may be invalid. Question the validity of ALL assumptions.

Research Summary, p. 331

Items to note – The passage states that if agar is cloudy, the bacteria have

reproduced successfully. It is then likely that if the agar is not cloudy, the bacteria did not successfully reproduce.

The water-soaked paper are the controls. If the paper inhibits growth as well as the antibiotics, the antibiotics were not the cause of the growth inhibition.

In this case, the water did not prevent the growth at all, since Plate C was entirely cloudy.

Due to the results of Exp’t B, we can reasonably determine that concentration of antibiotic matters, given when it was doubled, Plate B had a clear area around the disk.

p. 232

20. We know that if the agar is cloudy, bacteria is reproducing. It would then make sense that if the agar is clear, there was no bacterial growth.

21. Water-soaked paper disks are the control. A clear 2” circle around the paper disk would indicate that inhibition of the growth was not due to antibiotics.

22. The antibiotic treatments prevented growth, due to the clear agar, but the water disks did not. Dry disks were not mentioned. Concentration was not mentioned.

Passage VI

23. Effectiveness depends on concentration – B worked at double the concentration but not at the normal concentration for 22o tests.

24. Since the clear area never extends beyond 2”, the diffusion of the antibiotics is limited.

25. This is tricky because it wants you to think that A is more effective than B given the results of Exp’ts 2-3. However, at body temp (37 C), they were equally effective. Therefore, it would not matter which was prescribed if both were equal in price.

P. 333

31. In all three experiments, the sides with the plants had the smaller ruts.

32. Light winds did have an impact in Sandbox 133. They are comparing the rate at which rain

falls, not the total amount. Therefore, changing the time from 15 to 5 min with the same amount of rain would simulate a cloudburst

34. By keeping the soil the same, the investigator would know that the results were caused by the factor in consideration (water, slope, etc.) and not the soil.

Passage VII

35. Changing the slope increases the impact of gravity.

36. Obviously all three would increase the rate of erosions.

Conflicting Viewpoints

Items in CV:1. Predicting Results: requires you to make

predictions of results based on one of the presented viewpoints.

2. Spotting the Assumptions: requires you to ID assumptions regarding given data

3. Picking the Best Argument: requires you to ID the argument that supports or undermines the hypothesis.

Typical Items

Predict the results based on Scientist 1’s argument

Select a generalization that is most accurate given that Scientist 1’s argument is correct

Select the findings upon which Scientist 1 and Scientist 2 would NOT agree

Predict which observations support Scientist 1’s argument.

Select the weakest link in one of the arguments.Select the findings that support the

interpretations of both scientists.

CV Strategies

1. Be prepared to predict results based on each of the presented viewpoints – both should be considered possible/credible unless otherwise stated.

2. Watch for assumptions about viewpoints – they may NOT be justified.

3. Be prepared to ID which argument best addresses the issue. Pay attention to assumptions as they are often the weakest

part of an arugment.

4. ID the viewpoint’s main points and logical value – pay close attention to their differences.

Strategies

5. Read the viewpoints, but do NOT dwell on the details. You can always go back if you need to.

6. Read the answer choices carefully. Try to pick out the ‘distracters’ of each question These will often comprise 2-3 of 5 options They are related to the topic and are meant to look

valid; however they ignore the logic of the argument.

Nutshell – ID the main points and look for differences

p. 335

37. Theory 1 was the Octet Rule – that atoms want 8 electrons in their outer shell, except for hydrogen and helium with 2 electrons.

38. Theory 2 explains that according to Theory 1, Xe as a noble gas with 8 electrons already would not react.

39. BF3 has six valence electrons, which violates Theory 1 and cancels out A & B as options. Theory 2 also states that the compound shapes work to keep electrons as far apart as possible – hence D

Passage VIII

40. This question is merely asking for justification for Theory 2. H is misleading, as it implies that an atom w/o bonding can change its electrons. G is actually correct

41. Theory 2 states that valence electrons could go as high as 12. If XeF4 has 12 valence electrons, XeF5 would violate this 12 electron maximum