A student finishes an experiment and is left with three empty beakers that held liquids during the experiment. The best lab practice is to —
leave the beakers exactly as they are for the next student
turn the beakers upside down to drain in the sink
wash the beakers and air-dry them on a rack
take the beakers directly to a rack to dry
The scale drawings above show two catfish collected from a river. What is the difference in the actual body lengths of these catfish?
3 cm
9 cm
12 cm
24 cm
An experiment is being done to determine how light affects the growth of three different types of pea plants. Peas of each type are planted in several cups, and the cups are labeled X, Y, or Z to show the type of pea planted in each. Some cups are set in each of three locations to receive different amounts of light. Which of the following best shows how the plants should be arranged for the experiment?
Which set of equipment would be used to measure the boiling point of a liquid?
Balance, thermometer, and stopwatch
Test tube, hot plate, and balance
Stopwatch, test tube, and microscope
Beaker, hot plate, and thermometer
What is the volume of the liquid in the graduated cylinder?
43 ml
50 L
40 ml
6 L
Some data about the atmosphere of Mars are shown above. What conclusion can be made about the ability of humans to breathe Martian air?
Life support will be needed because the percentage of oxygen is too low.
It will be impossible to breathe because the percentage of nitrogen is too low.
Oxygen and nitrogen will make it possible for photosynthesis to produce food.
Humans will be able to breathe the air because oxygen is present.
An engineer measured how much energy a new type of wind turbine generated in locations with different wind speeds. A graph of the results is shown above. What is the best inference about operating the wind turbine at a location with wind speeds ranging from 0 to 8 km/h?
The turbine can reduce a household’s electricity bill.
The air is too dense to turn the rotor blades of the turbine.
The wind moves too slowly to generate enough energy.
Air pollution can be eliminated by using the turbine.
A foam dart is thrown toward a dartboard. The graph represents its motion. At about what speed is the dart traveling when it hits the dartboard, 7 meters from the starting point?
6.3 m/s
6.9 m/s
7.2 m/s
7.4 m/s
The table above shows that the more carbon atoms a compound has, the higher the compound’s boiling point. Based on the data in the table, a reasonable estimate of the boiling point of the next compound, C7H16, is —
70°C
99°C
120°C
142°C
The graph shows the movement of a car over time. What is the car’s average speed?
10 kilometers per hour
15 kilometers per hour
30 kilometers per hour
60 kilometers per hour
A cosmetics company markets bottles of nail polish remover with the label shown above. A consumer group concluded that the claim that the acetone is 100% pure is false. What is the most likely reason the consumer group reached this conclusion?
The acetone has probably dissolved some of the bottle.
The group has found that other claims by the company are false.
There are ingredients other than acetone in the nail polish remover.
Pure acetone is a flammable liquid, as stated on the label.