【題目】下列變化中，屬于化學變化的是( )。

A．金剛石加工成鉆石 B．金剛石切割大理石

C．白磷燃燒 D．冰變成水

【答案】C

【解析】

試題分析：白磷燃燒時會與氧氣反應生成五氧化二磷。反應中有新物質生成，為化學變化。

練習冊系列答案
相關習題

科目：初中地理 來源： 題型：

【題目】The boy likes eggs, but he____________ rice.

A. doesn’t likes B. don’t like

C. likes D. doesn’t like

查看答案和解析>>

科目：初中地理 來源： 題型：

【題目】空氣的主要成分①氧氣、②氮氣、③稀有氣體、④二氧化碳及其他氣體雜質，按體積分數(shù)由大到小的順序排列正確的是(　　)。

A. ①②③④ B. ②①③④

C. ①②④③ D. ②①④③

查看答案和解析>>

科目：初中地理 來源： 題型：

【題目】A

Lost & Found

Lost: Found: Schoolbag

My school ID card Is this your schoolbag?

Its number is 2007712 It’s black and white.

My name is Mary Brown. My name is Tony Green.

Please call 6956385. Phone: 2360731

Cindy,

Your red notebook is in the lost and found box.

Mike

【1】Mary’s school ID card number is __________.

A. 236-0731 B. 695-6385

C. 2007712 D. 695-8635

【2】 The schoolbag is __________.

A. green B. white

C. red D. black and white

【3】Mary’s phone number is __________.

A. 695-6385 B. 2007712 C. 236-0731 D. 659-6385

【4】 Tony’s last name is __________.

A. Brown B. Green C. Mike D. Cindy

【5】 Cindy’s __________ is in the lost and found box.

A. school ID card B. schoolbag

C. notebook D. baseball

查看答案和解析>>

科目：初中地理 來源： 題型：

【題目】下列現(xiàn)象能證明分子在化學變化中可分的是( )。

A．100 mL水和100 mL酒精混合后總體積小于200 mL

B．打開盛裝濃鹽酸的瓶蓋，濃鹽酸逐漸減少

C．氣態(tài)氧在加壓降溫時變?yōu)榈{色的液態(tài)氧

D．加熱氧化汞得到銀白色的汞和氧氣

查看答案和解析>>

科目：初中地理 來源： 題型：

【題目】飛機失事率小，生還率高。2014年3月8日馬航MH370“終結”于印度洋，無人幸存。2003年2月1日美國“哥倫比亞”號航天飛機失事，有關專家分析認為，其原因可能是航天飛機外部的石墨在空中脫落，擊中機翼。航天飛機表面覆蓋石墨可以起隔熱和保護作用，這主要是因為石墨( )。

A．能導電

B．密度小

C．熔點高、耐高溫、化學性質穩(wěn)定

D．硬度小，有潤滑作用

查看答案和解析>>

科目：初中地理 來源： 題型：

【題目】—Mom, I must go now. Peter is waiting for me at the cinema.

—OK! __________.

A. Good idea B. Good luck

C. Have a good time D. Best wishes

查看答案和解析>>

科目：初中地理 來源： 題型：

【題目】C

It is Sunday afternoon. Mary goes to do the shopping with her mother. Her mother wants to buy some food for supper. Mary wants to buy a new skirt and some school things. They come to a shop.

＂What does your shop sell?＂ Mary asks. ＂A lot of things.＂ The girl in the shop says. ＂You can buy food, drinks, clothes in our shop and school things, too.＂

Mary and her mother go in. There are many people in the shop. Mary finds a nice white skirt.

＂How much is the skirt?＂ Mary asks the girl in the shop.

＂It’s eighty yuan.＂

＂That’s too dear. Can I find a cheap one?＂

＂What about the green one? It looks nice. And it’s only thirty yuan.＂

＂OK, thanks a lot.＂

＂You are welcome.＂

After that, Mary buys some school things, too. Here mother buys a lot of food, like bread, cakes, meat and fish. They get home very late.

【1】Mary wants to buy a new skirt and _________.

A. some food B. some drinks

C. some clothes D. some school things

【2】Mary goes to do the shopping with her mother on ________.

A. Saturday afternoon B. Saturday morning

C. Sunday morning D. Sunday afternoon

【3】Mary buys a _________ skirt.

A. white B. green C. red D. dear

【4】The white skirt is __________.

A. ￥30 B. ￥110 C. ￥80 D. ￥100

【5】 The green skirt is ___________.

A. nice but dear B. nice and cheap

not nice but cheap D. not nice or cheap

查看答案和解析>>

科目：初中地理 來源： 題型：

【題目】下列防銹措施合理的是（ ）

A．經(jīng)常用水沖洗自行車鏈條

B．在鐵制暖氣片上刷“銀粉”

C．用“鋼絲球”打磨鋁鍋表面

D．用過的菜刀及時用鹽水清洗

查看答案和解析>>

同步練習冊答案