Question #d64a6

1 Answer
Aug 27, 2017

Answer:

#"1.2 g mL"^(-1)#

Explanation:

The idea here is that you can determine the volume of the object by looking at the difference between the water levels.

When you add the object to the water, a volume of water that is equal to the volume of the object will be displaced #-># the water level will rise in the cylinder.

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In your case, the volume of the water displaced by the object will be equal to

#"29.4 mL " - " 25.1 mL = 4.3 mL"#

This means that the volume of the object is equal to #"4.3 mL"#.

Now, in order to find its density, you must figure out the mass of exactly #1# unit of volume, i.e. of #"1m L"#, occupied by the object.

Since you know that #"4.3 mL"# have a mass of #"5.1 g"#, you can say that #"1 mL"# will have a mass of

#1 color(red)(cancel(color(black)("mL"))) * "5.1 g"/(4.3 color(red)(cancel(color(black)("mL")))) = "1.186 g"#

This means that the density of the object, i.e. its mass per unit of volume, will be equal to

#color(darkgreen)(ul(color(black)("density = 1.2 g mL"^(-1))))#

The answer is rounded to two sig figs.