下列说法正确的是
A.测定硫酸铜晶体中结晶水含量时,应先用称量纸称量一定质量的硫酸铜晶体,再将其转入到坩埚中加热 |
B.NH4+、Ag+、PO43-、Cl-能在溶液中大量共存 |
C.1 L 1 mol·L-1的碳酸钠溶液吸收SO2的量大于1 L 1mol·L-1硫化钠溶液吸收SO2的量 |
D.相同条件下,2 mol氢原子所具有的能量大于1 mol氢分子所具有的能量 |
The children loved their day trip, and they enjoyed the horse ride ______.
A.most | B.more | C.less | D.little |
Progress______ so far very good and we are sure that the work will be finished on time.
A.was | B.had been | C.has been | D.will be |
Charles was alone at home, with_______ looking after him.
A.someone | B.anyone | C.not one | D.no one |
It is often ______ that human beings are naturally equipped to speak.
A.said | B.to say | C.saying | D.being said |
I can’t leave. She told me that I ______ stay here until she comes back.
A.can | B.must | C.will | D.may |