下列各组溶液中,仅用组内物质就能鉴别出来,且均为无色溶液的是( ) A.NaOH 酚酞 Na2CO3 KClB.KCl Ca(OH)2 HCl NaNO3C.FeCl3 NaOH
在完全显性条件下,基因型AaBbcc与aaBbCC的两亲本进行杂交(这三对等位基因是独立遗传的),其子代中表现型不同于双亲的个体占全部子代的 A.0
去年国庆节期间,家住陕西的中学生小明随父母去北戴河旅游,他第一次见到了大海。海风吹过,海面上涌起滚滚的波涛。面对此情此景,小明不禁想
选词填空;阅读短文, 从方框中选择适当的单词填空(每词限用一次)。 My grandpa is over 70 years old. I like (1)________ with him. He used to live in a mountain village wh
已知在热的碱性溶液中,NaClO发生如下反应:3NaClO2NaCl+NaClO3。在相同条件下NaClO2也能发生类似的反应,其最终产物是( ) A.NaCl、NaClO
20.“品”是我国古代官吏的级别,分一到九品。在隋唐时期六部最高长官是正三品,到了明代提升为正二品。这主要是因为明代( ) A.官员晋升相对容易
She is very dear to us. We have been prepared to do it takes to save her life. A.whichever B.however C.whatever D.whoever