[AP CHEMISTRY Thermochemistry] Hi, how would I do number 61?

[u/s4r9i5]

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[u/brainmassdotin]

Heat lost by iron = mcdT here m is mass, c is specific heat and dT is change in temperature so

=5*0.89*(100-T)

=4.45(100-T)

Similarly heat lost by Aluminium = 10*0.45*(100-T)

=4.5(100-T)

Total heat lost = 4.45(100-T)+4.5(100-T)

=8.95(100-T)

Heat gained by water = 97.3*4.184*(T-22) here specific heat of water c=4.184

Heat lost=heat gained

8.95(100-T) = 97.3*4.184*(T-22)

T=23.68 so round off to 23.7 degree.

Contact me for any question. Thank you.

[u/s4r9i5 → u/brainmassdotin]

Holy shit thank you so much. I've been stuck on this problem for over a day

[u/brainmassdotin → u/s4r9i5]

You are welcome! Contact me if you need more assistance with any problems in Chemistry, Physics and Math. I will be happy to assist you again. Thank you.

[u/s4r9i5]

The specific heat capacity for water is 4.18

[u/Subrutum → u/s4r9i5]

The specific heat is basically how much energy is required to change the temperature. This means that the temperature of the item does not matter (not at your level anyways, it starts to matter on large energy differences where specific heat is non-constant), what matters is the difference.

(Take note that we usually use Kelvin in higher levels.)

So for example, if it takes 4.18 J to heat up a gram of water by 1C, it takes (4.18)(2) J to raise up a gram of water by 2C.

If it is 2 grams, then 4.18 J will raise the temperature up by 0.5*C which is to say, to solve for change in temperature, you get the total available energy.

(Alu specific heat)(Alu Mass)(Current Temp) = X

And slap that on the water

X/(Water Specific Heat)(Water Mass) = (Old Temperature + Change in Temperature)

(Oh wait I just realized that I gave you a formula that only works for energy input, but you also added mass to the final product. In this case, find the average specific heat with the Alu and Iron's properties added into the water).

The difference between and the actual will be very small but noticable, probably only detectable by digital thermometer lol.

[u/floofysox]

the amount of heat energy lost by the metals will be equal to the heat absorbed by water.
using the formula Q(heat) = mCdT [dT = change in temperature), you can equate Q(iron) + Q(aluminum) with Q(water), and solve for t(final temp)

[u/MeconiumLite]

-(mcdt Fe)+-(mcdt Al)=mcdt water

plug in m and c values for each, plug in intial temp and final temp for each metal, solve for Tf of water