Finding the Mass of a Sheet of Plastic Using Density Equation

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The density of the plastic is 0.75 g/cm^3, and the dimensions of the sheet are 10.0 m long, 1.0 m wide, and 1 cm thick. The mass is calculated using the formula m = DV, resulting in 75,000 g or 7.5 x 10^4 g. However, the calculation should consider significant figures, leading to a rounded answer of 8 x 10^4 g due to the least accurate measurement being 1 cm. Proper notation for fractions in density equations is emphasized, with a recommendation to use a forward slash instead of a backslash.
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The density of a certain type of plastic is 0.75 g/cm^3. If a sheet of this plastic is 10.0 m long, 1.0 m wide, and 1 cm thick, what is its mass?


Density= m\V
V= l x w x h



Rearranged the equation so that M = DV

m=(.75 g/cm^3)(100,000 cm^3)

and got m=75,000 g or 7.5 x 10^4 g.

I was wondering if I did the problem correctly, also, if it is in proper units? Thank you.
 
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Yes.

Also, note you should use a forward slash for text to indicate the fraction bar, D=m/V.
You showed the backslash.
 
Im looking at the same question in my chem book right now. Just also remember sig figs. When multiplying you must take the LEAST accurate piece of data to figure out your sig figs for your answer. In this case the least accurate piece of data would be 1 cm, which is 1 sig fig. So technically your answer should be rounded up to 8 x 10^4
 

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