2nd Case 21 Benchmark Study Guide Key

Which statement describes a scientific approach to their two predictions?

• A. Develop a compromise since the two students disagree.

• B. Measure the solubilities of salt, sugar, and baking soda in water.

• C. Measure the solubility of salt in water at several different temperatures.

• D. Poll a group of students to determine which prediction is the most widely accepted.

Which inference can be made from the data in the experiment?

• Heart rate is not affected by caffeine.

• Caffeine causes heart rate to increase.

• Caffeine has different effects on heart rate based on gender.

• Both sugar and caffeine cause an increase in heart rate.

Which statement from their discussion describes skepticism about the data?

• Kendall agrees with the data because it supports the data she collected.

• Faith concludes that taking showers conserves more water than taking baths. (true but not skepticism this is a conclusion)

• Neelly wonders if the dishwashing data is accurate since the range is so large.

• Hope recognizes that washing hands uses the least amount of water. (observation)

8 grams of hydrogen react completely with some oxygen to produce 72 grams of water. How many grams of oxygen are involved in the given reaction?

• 36 g

• 56 g

• 64 g

• 72 g

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

State the law of conservation of mass.

• In a chemical reaction, matter cannot be created or destroyed. The mass of the product must equal the mass of the reactants.

• Matter can be created in a chemical reaction.

• The mass of the reactants is always greater than the mass of the products.

• Energy is always conserved in a chemical reaction.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Omar is studying the periodic table and has learned the information shown. Based upon this information, which halogen forms the most stable compounds with other elements?

• astatine

• bromine

• chlorine

• fluorine

Should Darcy and Libby's classmates be skeptical of their conclusion?

• No. When litmus paper turns red, it indicates the substance is always a strong acid.

• No. All acids are strong and should be placed on the far left side of the diagram.

• Yes. They should repeat the test using pH test strips to determine the relative pH strength.

• Yes. They should repeat the litmus test at least 10 more times to make sure it still turns red.

Tags

NGSS.MS-PS1-2

What determines if an object is in motion?

• The presence of a force

• The object's speed

• The object's position

• The object's mass

Which graph represents a body moving at a constant speed?

• A. No motion

• B. Constant speed

• C. Constant speed, then stopping

• D. Speeding up

Tags

NGSS.MS-PS3-1

What is the average acceleration per second of the truck from 20 to 25 seconds?

• A. 2m/s/s

• B. 5m/s/s

• C. 10m/s/s

• D. 20m/s/s