A:海水
B:大理石
C:食醋
D:氧气
My parents want me to get further study to be ________ an engineer _______ a scientist, ________ I would like to be a famous surgeon doctor.
童年就像一幅画,色彩鲜艳,线条柔美;
童年就像____;
童年就像____。
当低倍镜换为高倍镜后( )
在含氯化钠杂质的纯碱样品12.4g中逐渐加入质量分数为7.3%稀盐酸,所加稀盐酸的质量与溶液的pH值的关系如图所示,计算: