Please see the attached file for the fully formatted problem(s).
An insulated tank, open to the atmosphere, contains 1,500 (lbm) of 40-wt-% sulfuric acid at 60oF. It is heated to 180oF by injection of live saturated steam at 1 atm, which fully condenses in the process. How much steam is required, and what is the final concentration of H2SO4 in the tank?
From steam tables the enthalpy of saturated steam at 1 atm is 1150.5 Btu/lb.
For acid at 40% and 60 F H_acid=-98 Btu/lb.
Use the first law for open systems:
sum(m_in H_in)=sum(m_out H_out)
m_steam *H_steam(sat, 1 atm) + m_acid* H_acid(40%, 60 F) = (m_steam+m_acid)*H_acid(x%, 180 F).
take the ratio ...
The amount of steam and the final concentration of H2SO4 are calculated.