Practice question

**Specific heat capacity** c = Q/(m ΔT) (J/kg·K), molar C = Q/(n ΔT), heat required to raise temperature, Q = m c ΔT, for water c=4186 J/kg·K, latent heat L = Q/m for phase change at constant temperature, fusion L_f and vaporization L_v, Q = m L, e.g., ice melting L_f=3.34×10⁵ J/kg, water vaporization 2.26×10⁶ J/kg. First Law: Δ Q = Δ U + Δ W . Δ Q = 830 , Δ W = -290 (work on system). 830 = Δ U - 290 ⇒ Δ U = 830 + 290 = 1120 J . Using first law ΔU = Q - W, W