1. For which properties can a student design an investigation of the electrostatic forces between molecules in a substance? (1 point)

Question

A. boiling point, but not melting point, surface tension, or vapor pressure
B. melting point, boiling point, surface tension, and vapor pressure ***
C. melting point and boiling point, but not surface tension and vapor pressure
D. surface tension and vapor pressure, but not melting point and boiling point

2. A student decides to conduct an investigation to determine the boiling points of water and ethanol. The student will heat samples of water and ethanol, and measure the temperature at which the samples boil. The student will conduct the investigation three times. Which aspect is missing from the experimental design? (1 point)

A. determining what data to collect
B. deciding on the number of trials to perform
C. determining the procedure
D. deciding on the appropriate equipment ***

3. To determine the melting point of ice, which procedure would best help measure the melting point temperature? (1 point)

A. Mix ice with water until equilibrium is reached but some ice remains that is still melting. ***
B. Mix ice with water until equilibrium is reached but some ice remains that is no longer melting.
C. Mix ice with water until just before equilibrium is reached but some ice remains that is still melting.
D. Mix ice with water until just before equilibrium is reached but some ice remains that is no longer melting.

4. Why is it important to conduct multiple trials of an investigation to determine the melting point of ice? (1 point)

A. It helps decrease human error.
B. It ensures that results are accurate. ***
C. It reduces the materials needed for the investigation.
D. It lets scientists manipulate data to meet their needs.

5. A student performs four trials of an investigation to determine the boiling point of water. How should the student handle the results? (1 point)

A. The student should take the average of the results from all four trials. ***
B. The student should take the average of the minimum and maximum value of the results.
C. The student should use the maximum value of the results.
D. The student should use the value that is closest to 100ºC.

I'd really appreciate some conformation on my answers. Thank you in advance!