Question

a botanist conducts an experiment. one plant is given nutrients and water, while another is given only water. the botanist concludes that the nutrients help the plant grow faster.

part 1: variables in the experiment

1. what was the test (independent) variable in the botanists experiment?
2. what was the outcome (dependent) variable in the botanists experiment?

part 2: physical properties of matter practice - use the list above to help answer the questions below.

1. a spoon is placed in hot soup, and the handle quickly becomes warm. which physical property of matter is being demonstrated in this scenario?
2. a scientist heats ice until it changes into liquid water. which physical property of matter is being demonstrated in this scenario?
3. a student connects a wire to a light - bulb and battery. the bulb lights when a metal strip is added, but not when a rubber strip is used. which physical property of matter is being demonstrated in this scenario?
4. two unknown powders are tested. one sinks in oil, while the other floats. which physical property of matter is being demonstrated in this scenario?

Explanation:

1. Heat transfer from hot soup to spoon shows thermal conductivity.
2. Changing ice to water is a phase - change property.
3. Metal allowing electricity to flow while rubber not shows electrical conductivity.
4. One powder sinking and the other floating in oil shows density.

For the botanist's experiment:

• The independent variable is the presence or absence of nutrients (the botanist gives nutrients to one plant and only water to the other).
• The dependent variable is the growth rate of the plant (the botanist concludes that nutrients help the plant grow faster based on comparing the two plants).

Answer:

1. Thermal conductivity
2. Phase - change
3. Electrical conductivity
4. Density
5. The nutrients
6. The growth rate of the plant