Prelab questions 1. If two liquids or solids have the same volume but different
ID: 862188 • Letter: P
Question
Prelab questions
1. If two liquids or solids have the same volume but different masses, which one will have the greater density? Explain.
2. In order to calculate the density of a substance, what two values do you need to know?
3. What is the approximate density of water?
4. Should you use the same digital balance for all data collection? Explain
5. Is it important to use the same volume for each trial? Why or why not?
Post Lab questions
1. Use common sense to answer this question: A student used a volumetric pipette to determine the density of distilled water. Before obtaining data, the student dried the volumetric pipette in an oven to remove any water present in the pipette. Was this necessary? Explain
2. Your goal is to determine the density of a metal ball. The mass of the bal is 15.0g. When the ball is placed in a graduated cylinder containing water, the volume of the water andthe ball is 15.0 mL. The volume of the water before the ball was added t the graduated cylinder was 10.0 mL. What is the density of the metal ball?
3. If you did not purge all the air out of the burette tip, will your density value be too high or too low?
Explanation / Answer
1-solid have more density because atomes or molecule are closer in solid than liquid.
2-to know density of substance we have to know mass, &volumeof substance.
d=m/v
3-1g/ml or1g/cm^3
4-we used different balanced for diff. data collection e.g.electronic balanced, analitical balanced,toploader balanced,for more precision micro balanced as for our need
5-yes, because we get different value of density when we used diff. volume.
lab
1-this is right way to get accurate value of volume.
2-mass of ball=15gm
volume of ball=15-10=5ml=5cm^3
d=m/v=15/5=3g/ml or5g/cm^3
3-high