104型紧急阀紧急勾贝杆上紧急室稳定限制孔孔径为()。
A.0.5mm
B.1.0mm
C.1.2mm
D.1.6mm
参考答案:D
数据通信
298K时
Ca(s) + C(s,石墨)+ 3/2O2(g)= CaCO3(s) △H1=-1206.8kJ·mol-1 ①
Ca(s) + 1/2O2(g)= CaO(s) △H2=-635.1kJ·mol-1 ②
C(s,石墨)+ O2(g)= CO2(g) △H3=-393.5 kJ·mol-1 ③
计算CaCO3(s) = CaO(s) + CO2(g) △H4= ? [ ]
A.+178.2 kJ·mol-1
B.-178.2 kJ·mol-1
C.+287.2 kJ·mol-1
D.-287.4 kJ·mol-1