下列物质① 食盐 ② 酒精 ③ 金刚石 ④ 稀硫酸 ⑤ 氧气 ⑥ 碳酸钠在生产生活中有广泛用途。请按以下要求填空。（填序号）
（1）炼钢时，将生铁中所含的过量的碳变为气体而除去，使用的是 。
（2）装在钻探机的钻头上，用来钻凿坚硬岩层的是 。
（3）可将碘溶于 中，制成医用消毒剂。
（4） 可用于调味和腌渍蔬菜。
（5） 可用来除去铁器表面的铁锈。
（6）家庭里蒸馒头或洗涤衣物，有时用到 。
（1）⑤
（2）③
（3）②
（4）①
（5）④
（6）⑥
| 阅读短文，把方框中的选项还原到短文中，使短文完整、通顺，然后为第5题选择正确选项。 | |
| Fire can help people in many ways. But it can also be very harmful. Fire can heat water, warm your houses, give light, and cook food. 1. It can burn trees, houses, animals, or people. Sometimes big fires can burn forests. Nobody knows for sure (确实) how people began to use fire. But there are many interesting old stories about the first time a man or woman started a fire. One story from Australia tells about a man very, very long time ago. 2. Today people know how to make a fire with matches. Children sometimes like to play with them. But matches can be very dangerous. One match can burn a piece of paper, 3. A small fire can become a big fire very fast. Fires kill many people every year. So you must be careful with matches. 4. Fires need oxygen. Without oxygen they die. There is oxygen in the air. Cover a fire with water, sand, or in an emergency (紧急情况), with your coat or something else. This keeps the air away from a fire and kills it.
| |
| 5. Which of the following is NOT talked about in the passage? | |
[ ] | |
| A. Fire can be used to heat water. B. Fire can be used to warm our houses. C. Fire can be used to cook food. D. Fire can be used to dry our clothes. |