A:将固体加入容量瓶中溶解并稀释至刻度线,配制成一定物质的量浓度的溶液
B:向盛有NaOH的烧杯中加蒸馏水使其溶解,并立即转入容量瓶中
C:用托盘天平称取10.60 g的Na2CO3固体,溶于1 L的水可配成0.1 mol/L的溶液
D:检查容量瓶是否漏水的方法是:往容量瓶中加水,塞好瓶塞,将容量瓶倒过来,若不漏水,将瓶塞旋转180°,再倒过来,看是否漏水
选词填空 根据短文内容,从方框中选择恰当的单词完成句子并填写在答题卡对应的横线上。部分单词在填入前需进行词形转换,每个单词只能用一次,每空只能写一词。
problem less important healthy recycle
It is very ____ to deal with the rubbish in cities. This is because rubbish not only pollutes the environment but also does harm to people's ____ . We are trying to find some ways of dealing with the rubbish. First, the rubbish can be divided into different kinds. Newspaper and glass can be ____ . Used tins can be made into beautiful handicrafts(手工艺品). Polluted water is a big ____ . It must be dealt with properly before we let it flow into the river. Some harmful rubbish can be buried(埋)so that it will cause ____ pollution.