how much heat in joules would be required to raise the temperature of 40 g of aluminum (CAL =.21 cal g/C) from 19. c to 31.2 c

2,220 J

Explanation:

In order to be able to determine how much heat is required to increase the temperature of your sample of water from

35.0 ∘C to 70.0 ∘C

, you need to know the value of water's specific heat.

As you know, a substance's specific heat tells you how much heat is required to increase the temperature of

1 g

of that substance by 1∘C.

Water has a specific heat of about

4.18 Jg∘C

. This tells you that in order to increase the temperature of

1 g

of water by 1∘C

, you need to provide it with 4.18 J

of heat.

Now, here's how you can think about what's going on here. in order to increase the temperature of

4.18 g

of water by 1 ∘C, you would need 4.18

times more heat than water's specific heat value.

Likewise, in order to increase the temperature of 4.18 g

of water by 4.18 ∘C, you'd need (4.18*4.18)

times more heat than water's specific heat value.

In your case, you need to increase the temperature of 15.2 g of water by

35.0 ∘C, which tells you that you're going to need (15.2 * 35)

times more heat than water's specific heat value.

Mathematically, this is expressed as

q = m ⋅ c ⋅ Δ T, where q - heat absorbed/lost m - the mass of the sample c

- the specific heat of the substance

Δ T - the change in temperature, defined as final temperature minus initial temperature

Plug in your values to get

q = 15.2 g ⋅

4.18 Jg ∘C⋅ (70.0 - 35.0) ∘ C

q = 2223.76 J

Rounded to three sig figs, the answer will be

q = 2,220 J