—What made her so upset?
—______the necklace ______yesterday.
A. Lost, bought
B. Lost, buying
C. Losing, having bought
D. Losing, bought
第1题:
第2题:
第3题:
下列哪一个反应的热效应等于硫酸的生成焓?()
A.SO3(g) + H2O(l ) = H2SO4(l)
B.SO3(g) + H2O(g) = H2SO4(l)
C.Na2SO4(s) + 2HCl(l) = H2SO4(l)
D.H2(g) +S(s)+2O2(g) = H2SO4(l)
第4题:
第5题: