Question

PLEASE HELP!
The specific heat of octane, C8H18(l), is 2.22 J/(g⋅K).
How much heat is needed to raise the temperature of 76.0 g of octane from 10.6 ∘C to 26.0 ∘C?
Express your answer in joules to three significant figures.

Answer 1

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 • $10^{3}$

or

Q = 2590 J

Hope this helps!

Answer 2

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)