# chemistry

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it says "how many joules of energy would be required to heat 29.8 grams of carbon from 25.5 C to 79.3 C. (s= .71 Joules / grams times carbon) & the formula is Q= M x C x delta T .

• chemistry -

What's your problem? You have the formula and the numbers. Plug and chug.

• chemistry -

How?

• chemistry -

q = ?
m = mass = 29.8 grams
c = specific heat = .71 J/g*C
delta T = 79.3-25.5 = 53.8

q = 29.8 x 0.71 x 53.8 = ? joules.

It would be helpful if you told me why you couldn't do that, please.

• chemistry -

So the answer would be 1233.5 joules?

• chemistry -

Not according to my calculator. Did you punch in the right numbers?

• chemistry -

Yeah. What did you get?

• chemistry -

1138.3004?

• chemistry -

You couldn't have.
29.8 x 0.71 x 53.8 = 1138.3 J. If you typed the problem in right and that's 0.71 the answer should be rounded to 2 s.f. which is 1.1E3 J. If that was really 0.710 then the answer should be rounded to 1.14E3 J.
It still would be helpful to know the real problem here. I hope this isn't a case of just not doing the work and getting someone on line to do it for you.

• chemistry -

1138.3004 is right. Now round it to either two or three s.f. depending upon how many you have in that 0.710 number.