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

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !

pv=nrt

explanation: