下列说法正确的是（ ）
A．书写热化学方程式时，只要在化学方程式的右端写上热量的符号和数值即可
B．凡是在加热或点燃条件下进行的反应都是吸热反应
C．表明反应所放出或吸收热量的化学方程式叫做热化学方程式
D．氢气在氧气中燃烧的热化学方程式是：2H2（g）+O2（g）═2H2O（l）；△H=-483.6kJ
A．书写热化学方程式时，要在化学方程式的右端写上热量的符号和数值，还要注明各物质的状态，故A错误；
B．有的放热反应也需要加热，所以在加热或点燃条件下进行的反应不一定是吸热反应，故B错误；
C．热化学方程式的概念：表明反应所放出或吸收热量的化学方程式叫做热化学方程式，故C正确；
D．反应热的单位错误，所以氢气在氧气中燃烧的热化学方程式是：2H2（g）+O2（g）═2H2O（l）；△H=-483.6 kJ/mol，故 D 错误；
故选C．
A. It's not far away from all the other cities in China.
B. You have to travel long by land from Guangdong to Beijing.
C. It's not far away from us all.
D. It's not far away from Guangdong.
3. From the passage, we know ______ has the longest way to Guangdong except Beijing. [ ]
A. Wuhan
B. Changsha
C. Shanghai
D. Kunming
4. Which one is WRONG? [ ]
A. Wuhan is very hot in summer.
B. It's as warm in winter in Kunming as Beijing.(as...as 和...一样)
C. It's 1084 kilometers from Wuhan to Guangdong.
D. It's warm in winter in Guangdong.
5. It takes more than 30 hours to arrive in Beijing from ______ by train.[ ]
A. Guangdong
B. Kunming
C. Changsha
D. Shanghai