题目内容

【题目】下列物质溶于水时，溶液温度明显降低的是（ ）

A．氯化钠

B．硝酸铵

C．浓硫酸

D．氢氧化钠

【答案】B

【解析】A项，氯化钠溶于水时吸收的热量和放出的热量相当，溶液温度基本保持不变．B项，硝酸铵溶于水时吸收的热量多，溶液温度明显降低．C项，浓硫酸稀释时放出的热量多，溶液温度明显升高．D项，氢氧化钠溶于水时放出的热量多，溶液温度明显升高．

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相关题目

【题目】写出下列溶液中溶质的化学式。

溶液

溶质

可用制取氢气的稀硫酸溶液

用于医疗消毒的过氧化氢溶液(俗称双氧水)

医疗消毒用的高锰酸钾溶液(俗称紫药水)

医疗用的0.9%的氯化钠注射液(生理盐水)

澄清的石灰水

【题目】I want __________ to the supermarket with my sister this afternoon.

A. go B. to go C. going D. goes

【题目】B

Winter Sale!

Winter is coming. So we are having a big and endofautumn sale. Look at the prices!

A blouse：$5

A coat：$20

A silk(丝绸) skirt：$28

A pair of trainers：$30

A pair of jeans：$30

Will you come to Reborn Fashion Shop on the 2nd floor of New Century Shopping Mall between Friday and Sunday?

Cash Back!

Spend twenty dollars in our shop, and we will give you five dollars back. Spend 40 dollars, and you will get 10 dollars back.

Remember：only at weekends

You are welcome to Happy Times Doll Shop on the first floor of New Century Shopping Mall.

Closing Down Sale!

Come to our shop next Monday. There is a discount(打折) on every kind of chocolate. And we will give you a big box of sweets for free(免费的) if you spend more than 20 dollars in our shop. So come to Sweetheart Chocolate Shop on the first floor of New Century Shopping Mall.

【1】 How many shops are there in this advertisement(广告)?

A. Six. B. Four. C. Three. D. Two.

【2】 What is the price of a silk skirt in Reborn Fashion Shop?

A. $ 5. B. $ 20. C. $ 28. D. $ 30.

【3】If(如果) you spend 20 dollars in Happy Times Doll Shop, how much will you get back?

A. 5 dollars. B. 15 dollars.

C. 20 dollars. D. 40 dollars.

【4】If you want to buy clothes at a lower price, where should you go?

A. Happy Times Doll Shop.

B. Reborn Fashion Shop.

C. Sweetheart Chocolate Shop.

D. The first floor of New Century Shopping Mall.

【5】What does the underlined word mean in Chinese?

A. 商品 B. 发票 C. 赠品 D. 现金

【题目】为预防自行车生锈，下列做法中不合理的是（ ）

A．车架表面喷涂油漆

B．钢圈表面镀防护金属

C．链条表面涂机油

D．露天放置，日晒雨淋

【题目】各种洗涤剂广泛进入人们的生活中，下列洗涤中所用洗涤剂具有乳化功能的是（ ）

A．用汽油除去衣服上的油污

B．用洗洁精清洗餐具上的油污

C．用水洗去盘子中的水果渣

D．用醋洗去水壶中的水垢

【题目】 Eddie eats __________ food every day. Hobo thinks he needs some __________.

A. too much; exercises B. too many; exercises

C. too many; exercise D. too much; exercise

【题目】书面表达(15分)

你每天的家庭作业都是什么时间完成的？需要父母的帮忙吗？请你结合上面文章的内容，写一篇短文。内容包括：

1. 每天大概花多少时间做作业？

2. 能不能自觉独立地完成自己的作业？

3. 你怎样看待家庭作业？

要求：

1. 不能照抄原文；不得在作文中出现学校的真实名称和学生的真实姓名。

2. 语句连贯，词数在80个左右。作文的开头和结尾已经给出，不计入总词数。

I often spend nearly two hours to do my homework every day. ______________________________________

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

If so, we will feel tired and don’t want to do it carefully.

【题目】很多化学反应都在溶液中进行的原因是（ ）

A、易于操作 B、反应速率快 C、不需加热 D、设备简单

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