下列实验能达到预期目的是
选项 |
实验内容 |
实验目的 |
A. |
测同温同浓度下的Na2CO3和Na2SO3水溶液的pH |
确定碳和硫两元素非金属性强弱 |
B. |
取一定质量的铝片,与过量的NaOH溶液充分反应,溢出的气体通过硅胶后,测其体积 |
确定铝片中氧化铝的含量 |
C. |
取久置的Na2SO3溶于水,加硝酸酸化的BaCl2溶液 |
证明Na2SO3部分被氧化 |
D. |
向CH2=CHCH2OH中滴加酸性KMnO4溶液 |
证明CH2=CHCH2OH中含有碳碳双键 |
I’m sure that your letter will get______ attention. They know you’re waiting for the reply.
A.continued | B.immediate | C.careful | D.general |
All the dishes in this menu, ______ otherwise stated, will serve two to three people.
A.as | B.if | C.though | D.unless |
The children loved their day trip, and they enjoyed the horse ride ______.
A.most | B.more | C.less | D.little |
I can’t leave. She told me that I ______ stay here until she comes back.
A.can | B.must | C.will | D.may |
—— Do you mind my opening the window? It’s a bit hot in here. —— ______ , as a matter of fact
A.Go ahead | B.Yes, my pleasure![]() |
C.Yes, I do | D.Come on |