5．以下操作会使结果偏高的是：

　 A．在转移液体前容量瓶中有少量蒸馏水；

B．定容摇匀后，液面已低于容量瓶刻度线，此时再加水；

C．转移时有少许液体沿容量瓶外壁流到实验桌上；

D．定容时俯视液面。

4．下列各项中在容量瓶上必须表明的是：

①容量　 ②刻度线　 ③温度　 ④压强　 ⑤物质的量浓度　 ⑥用于配制酸溶液或碱溶液

A．①②③　　　 　 B．①③⑤　 　 C．②④⑥　　　 　 D．①②③⑤⑥

3．实验室需用480mL 0.100 mol/L的CuSO₄溶液，下列配置方法正确的是：

　A．称取7.68g　CuSO₄固体，加入　480mL水　 B．称取12.0g　胆矾配制成　480mL溶液　

C．　称取8.0g　CuSO₄固体，加入　500mL水　 　D．称取12.5 g　胆矾配制成　500mL溶液

2．下表中物质的分类组合完全正确的是：

1．许多国家十分重视海水资源的综合利用。不需要化学变化就能够从海水中获得的物质是：A．氯、溴、碘　　　　　 B．钠、镁、铝　　　　　 C．烧碱、氢气　　　　　　 D．食盐、淡水

4．短文的第一句已给出，不计人句子总数。

　　 A healthy diet and regular exercise may help to prevent obesity among children．

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[答案]

　　 　A healthy diet and regular exercise may help to prevent obesity among children.

　　　 Nowadays, most children get into the habit of eating too much junk food and snacks. Besides, they spend a lot of time lying on the sofa, watching TV, playing computer games but do little exercise.　 As a result, they put on so much weight that sometimes they may find it difficult to climb the stairs.

　　　 It is time for children to change the unhealthy life style. Only when they begin to have a balanced diet and also take part in various sports activities such as swimming, skating, running and playing basketball can they become as fit as before

3．可适当增加细节，使用必要的连接词。

2．将5个句子组织成连贯的一篇短文。

3．只有平衡的饮食和参加锻炼才能使人健康。

(写作要求)

2．当代儿童大多数有吃垃圾食品和快餐的习惯又懒于锻炼，看电视或玩电脑游戏时间太长。