问题
选择题
—I'm going to buy some _______.What about you?
— I'm going to buy some _______. [ ]
A. tomatoes, potatoes
B. tomatoes, potatoes
C. tomatoes, potatoes
D. tomatoes, potatoes
答案
答案:A
—I'm going to buy some _______.What about you?
— I'm going to buy some _______. [ ]
A. tomatoes, potatoes
B. tomatoes, potatoes
C. tomatoes, potatoes
D. tomatoes, potatoes
答案:A
室温下,下列叙述正确的是( )(溶液体积变化忽略不计)
① | ② | ③ | ④ | |
溶液 | 氨水 | 氢氧化钠溶液 | 醋酸 | 盐酸 |
pH | 11 | 11 | 3 | 3 |
A.分别将等体积的③和④加水稀释100倍,所得溶液的pH:③<④
B.在①、②中分别加入氯化铵固体,两溶液的pH均增大
C.①、④两溶液等体积混合,所得溶液中c(Cl-)>c(NH4+)>c(OH-)>c(H+)
D.②、③两溶液混合,若所得溶液的pH=7,则c(CH3COO-)>c(Na+)