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

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

give me abc and i will get it for u.