If you have water and copper and both 125cm of volume, then why does the water have less mass?

Question

This is my daughter's science homework and I am completely baffled.

This is the exact question-
Why would the mass of 5cm to the 3rd power of water be less than the mass of the same volume of copper?'

yell_f!re · Accepted Answer

here's a simple answer: density. water is less dense than copper.

water has a density of 1.00 g/mL whereas copper's density is around 8.9 g/mL.

so if you have 125 cm^3 of each substance, the water, with a density of 1.00g/cm^3 <yes, cm^3 is the same as 1 mL>, will be 125 g. but copper will be (125 cm^3)(8.9g/cm^3) so about 1112.5 g.

in my books, 1112.5 grams is heavier than 125 grams....... 

how old is your daughter? when do they start teaching this in school...were you absent that day?

Technobuff · Answer

Because its density (the amount (mass) of the matter in a given volume of the copper), is greater.
If you like, the matter in copper is "packed in tighter".

If you have water and copper and both 125cm of volume, then why does the water have less mass?

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