Chemical Reactions and Properties of Air

Dr. Curie is studying the reaction rate (speed) of a new chemical compound. She records the amount of product formed over time in a line graph. If the graph shows that 2 grams of product were formed after 5 minutes, and 8 grams were formed after 15 minutes, what was the average rate of product formation in grams per minute during this time interval?

• 1.875 g/min

• 0.533 g/min

• 0.600 g/min

• 0.400 g/min

A group of students conducted the famous Elephant Toothpaste experiment with different concentrations of hydrogen peroxide. They recorded the maximum height of foam produced in a bar graph. If the graph shows that 3% hydrogen peroxide produced 30 cm of foam, 6% produced 45 cm, and 9% produced 60 cm, how much more foam did the 9% solution produce compared to the 3% solution?

• 10 cm

• 15 cm

• 30 cm

• 45 cm

In a pie chart showing the composition of air, nitrogen takes up 78% of the circle, oxygen takes up 21%, and other gasses make up the rest. What percentage do the other gasses occupy in the pie chart?

• 1%

• 22%

• 57%

• 77%

Professor Boyle is tracking the pressure of a gas as he changes its volume. He plots his results on a line graph. If the graph shows that when the volume is 2 liters, the pressure is 4 atmospheres, and when the volume is 4 liters, the pressure is 2 atmospheres. Which TWO statements are most accurate?

• The larger the volume, the greater the pressure.

• The smaller the volume, the greater the pressure.

• The slope of this change in volume and pressure is downward.

• The slope of this change in volume and pressure is upward.

A class performed the Mentos and Diet Coke experiment with different numbers of Mentos candies. They recorded the height of the soda fountain in a bar graph. The graph shows that 3 Mentos produced a 3-foot fountain, 5 Mentos produced a 5-foot fountain, and 7 Mentos produced a 7-foot fountain. Based on this pattern, how tall would you expect the fountain to be with 9 Mentos?

• 9 feet

• 12 feet

• It is impossible to predict without conducting the experiment.

• It is impossible to determine without knowing how much diet Coke was used.

Which of the following statements best describes accuracy?

• The closeness of measurements to each other

• The exactness of a measurement tool

• The closeness of a measurement to the true or accepted value

• The ability to measure a small quantity

If a set of measurements are all very close to each other but far from the true value, they are:

• Accurate but not precise

• Precise but not accurate

• Both accurate and precise

• Neither accurate nor precise

What is the key difference between weight and mass?

• Mass depends on gravity, weight does not

• Weight is a measure of inertia, mass is not

• Mass is the amount of matter in an object, weight is the force of gravity on that object

• Weight is constant, mass varies with location

Which of the following remains constant regardless of location?

• Weight

• Mass

• Both weight and mass

• Neither weight nor mass

Which of the following best describes a scientific law?

• A very detailed explanation of some aspect of the natural world

• A prediction about future events based on current knowledge

• A statement that describes a consistently observed phenomenon in nature

• An educated guess that can be tested through experiments