Chemistry
posted by j on .
The density of gold is 19.3 g/cc (g/ml). If a gold rod has a diameter of 4.20cm and 8.0 cm long. What is the mass?
I just need to know if I did this right...
r= 2.1
3.14 x 2.1^2 x 8.0 = 110.835g
19.3 g/cc x 110.835g = 2139.12 g/ml
m = 2139.12

The digits are ok.
If your prof watches significant figures, your final answer should be rounded to 2.14 x 10^3 and you omitted the units; i.e., grams. 
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Would I just add 46.0g + 173g?
I can't remember how to do it... 
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