【单选题】-What do you think of the party, Laura? -Oh, great! Thank you for _____ the chairs _____ me. [ ]
【单选题】下列能正确表示水解的离子方程式是
A.
CH 3 COOH + H 2 O CH 3 COO - + H 3 O +
B.
NH 4 + + H 2 O NH 3 ·H 2 O + H +
C.
CO 3 2- + 2H 2 O H 2 CO 3 + 2OH -
D.
Br - + H 2 O HBr + OH -
【单选题】以色列和巴勒斯坦都把哪个城市定为首都 [ ]
【单选题】按气态氢化物稳定性递增顺序排列的一组是( )
C.
SiH 4 PH 3 H 2 O H 2 S
【单选题】CH 4 、NH 3 、H 2 O、HF分子中,共价键的极性由强到弱的顺序是( )。
【单选题】"Maggie, Barbara, I'd like to introduce our new colleague Laura." Maggie:" Hi, Laura, welcome to the office." Barbara:"Welcome, please let us know if there is anything we can do for you." Laura: "____...
B.
It's lovely to meet you both.
【单选题】以色列和巴勒斯坦都把其定为首都的城市是( )
【单选题】下列电离方程式中,正确的是( )
A.
NH 3 ?H 2 O═NH 4 + +OH -
C.
CH 2 COOH+NH 3 ?H 2 O?CH 3 COO - +NH 4 + +H 2 O
【单选题】— Do you know Laura’s address? — _____________. As a matter of fact, I don’t know any Laura, either.
【单选题】下列各组物质全部是弱电解质的是
B.
MgSO 4 CH 3 COOH CH 3 CH 2 OH
D.
H 2 O NH 3 ·H 2 O H 3 PO 4