# thermochemistry

posted by
**crystine cole** on
.

what is the mass of a lead block that if heated to 100.0 dgrs C and placed in a container with 50.0g of ice at 0.00dgrs C produces a final water sample of 15.0dgrs C? Sh of Pb= 0.128J/g dgrsC step by step solution and answer

q1 for Pb block = mass x sp.h. x (Tf - Ti).

mass Pb = X

sp.h. Pb = listed

Tf = 15.0

Ti = 100.0

q2 for ice at zero degrees to melt to water at zero degrees is mass x delta H fusion. Be sure to use J/g for the unit.

mass = 50.0 g

delta H = ?? J/g.

q3 for water at zero to be heated to 15.0 degrees = mass x sp.h. x (Tf - Ti)

mass H2O = 50 g.

sp.h. water = ?? J/g*C.

Tf = 15.0

Ti = 0.0

q1+q2+q3 = 0

solve for X.

The sum of the heats gained is zero (some lose heat).

Heat gained lead+ heatgainedice=0

m*Cpb*(100-Tf)+ 50*Heatfusionice + 50*cwater*(Tf-0)=0

you are given Tf, solve for m.