1375 J of heat energy are added to a 50.0 g sample of copper, which increases temperature from 22.8 C to 94.2 C. Calculate the specific heat of copper.

0.385 J/G ° C

Explanation:

Q = mcΔT

Q = 1375 J

m = 50.0 g

c = Unknown

ΔT = 94.2 C - 22.8 C = 71.4 C

1375 J = (50.0 g)(x)(71.4 C)

1375 J = (3570 g/C)(x)

0.385154062 J/G ° C = x

Recall your answer must have 3 significant figures

x = 0.385 J/G ° C

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.