问题
选择题
Dad ________ a good idea to deal with the embarrassing problem. [ ]
A. got along with
B. thought over
C. came up with
D. worked on
答案
答案：C
搜题请搜索小程序“爱下问搜题”
Dad ________ a good idea to deal with the embarrassing problem. [ ]
A. got along with
B. thought over
C. came up with
D. worked on
答案：C
下表中列出了25℃、101kPa时一些物质的燃烧热数据
| 物质 | CH4 | C2H2 | H2 |
| 燃烧热／kJ/mol | 890.3 | 1299.6 | 285.8 |
已知键能：C—H键：413.4 kJ/mol、H—H键：436.0 kJ/mol。
则下列叙述正确的是
A．C≡C键能为796.0 kJ/mol
B．C—H键键长小于H—H键
C．2H2(g)+O2(g)=2H2O(g) △H=﹣571.6 kJ/mol
D．2CH4(g)=C2H2(g) +3H2(g) △H=﹣376.4 kJ/mol