Calculate change in enthalpy when 39 g acetylene is completely burnt with oxygen and enthalpy of combustion of acetylene is $$-$$1300 kJ/mol.
(At. mass C = 12, H = 1)
An ideal gas on isothermal reversible compression from 10L to 5L performs 1730J of work at 300 K. Calculate number of moles of gas involved in compression? (R = 8.314 J K$$^{-1}$$ mol$$^{-1}$$)
A sample of gas absorbs $$4000 \mathrm{~kJ}$$ of heat and surrounding does $$2000 \mathrm{~J}$$ of work on sample. What is the value of $$\Delta U$$ ?
If $$38.55 \mathrm{~kJ}$$ of heat is absorbed, when 6.0 of $$\mathrm{O}_2$$ react $$\mathrm{CIF}$$ according to reaction.
$$2 \mathrm{CIF}(g)+\mathrm{O}_2(g) \longrightarrow \mathrm{Cl}_2(g)+\mathrm{OF}_2(g)$$
What is the standard enthalpy of reaction?