在标准状况下H2和Cl2的混合气体a L，经光照后完全反应，所得气体恰好能使b mol的NaOH完全转化为盐，则a、b的关系不可能是下列的（ ）
A．b=
B．b>
C．b≥
D．b<
答案：C
所发生的反应有：H2+Cl2
2HCl HCl+NaOH====NaCl+H2O
若Cl2过量还有：2NaOH+Cl2====NaCl+NaClO+H2O
由以上反应可知：n(NaOH)=2n(Cl2),故可用极值法求解。
若a L全为H2时，耗NaOH的物质的量为0,若a L全为Cl2时，消耗NaOH量最大：
×2 mol=
mol,故对二者混合气体耗NaOH量应介于0与mol之间。
SUNNY SCHOOL We are a bilingual(双语) school for children (From 6 to 15). We want a cook, a library assistant, a sports coach(教练) and a language teacher.
A. Lily, 4 years old. B. Tom, 11 years old. C. Nancy, 15 years old. 小题2:Who is not wanted by Sunny School? A. A math teacher. B. An English teacher. C. A library assistant 小题3:We know ______ don`t need to speak English in Sunny School. A. the sports coach B. the cook C. the library assistant 小题4:The Sunny School wants a teacher ________. A. aged between 25 and 40 B. who can cook Western food C. who can speak English and Chinese 小题5:The Sunny School wants a sports coach who majors in ________. A. English B.P.E. C.Chinese |