选择符号“>、=、<”填入下列空格: (1)理想气体恒温膨胀:W_____0,Q_____0,△U_____0,△H_____0; (2)理想气体恒压膨胀:W_____0,Q_____0,△U_____0,△H_____0; (3)理想气体节流膨胀:W_____0,Q_____0,△U_____0,△H_____0; (4)实际气体绝热自由膨胀:W_____0,Q_____0,△U_____0,△T_____0; (5)实际气体恒温自由膨胀:W_____0,Q_____0,△U_____0,△H_____0; (6)实际气体节流膨胀:W_____0,Q_____0,△U_____0,△H_____0; (7)在273.15K、pθ下,冰融化成水,以冰和水为体系:Q_____0,W_____0,△U_____0,△H_____0; (8)在一绝热的刚壁容器中发生一化学反应,若体系的压力升高了,则体系:Q_____0,W_____0,△U_____0,△H_____0;