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3 years ago

PLEASE HELP!

Chemistry

2 answers:

grandymaker [24]3 years ago

4 0

Answer:6,985.008

Explanation:

so the hear formula is mass times specific heat times change in temperature (kelvin) so what i did was got the change in temperature (41.4 K) and multiplied that times 2.22 J/(g•K)and multiplied that by 76 grams of Octane to get the Answer (not in scientific notation)

pogonyaev3 years ago

3 0

Answer:

Q = 2.60 • $10^{3}$ J

Explanation:

Our specific heat capacity equation is:

Q = mC∆T

Q is the energy in joules.

m is the mass of the substance.

∆T is the temperature chance.

Let's plug in what we know.

We have 76.0 g of octane
The specific heat capacity of octane is 2.22 J/(g•K)
The temperature increases from 10.6º to 26.0º (a 15.4º increase)

Q = 76.0(2.22)(15.4)

Multiply.

Q = 2598.288

We want three significant figures.

Q = 2.60 • $10^{3}$

Q = 2590 J

Hope this helps!

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