【題目】下列關(guān)于硅的說法中,不正確的是( )

A.硅是非金屬元素,它的晶體單質(zhì)是灰黑色有金屬光澤的固體

B.硅的導(dǎo)電性能介于導(dǎo)體和絕緣體之間,是良好的半導(dǎo)體材料

C.硅的化學(xué)性質(zhì)不活潑,常溫下不與任何物質(zhì)反應(yīng)

D.加熱到一定溫度時,硅能與氯氣、氧氣等非金屬反應(yīng)

【答案】C

【解析】硅雖然外形像金屬(有金屬光澤),但實(shí)際上屬于非金屬;硅既有金屬性,又有非金屬性,其導(dǎo)電性也介于導(dǎo)體和絕緣體之間,是良好的半導(dǎo)體材料。硅的化學(xué)性質(zhì)不活潑(尤其是在常溫下),但常溫下仍能與氟氣、氫氟酸和NaOH溶液等發(fā)生反應(yīng),加熱至一定溫度時,硅能與氯氣、氧氣等非金屬發(fā)生反應(yīng)。

練習(xí)冊系列答案
相關(guān)習(xí)題

科目:高中地理 來源: 題型:

【題目】假定英語課上老師要求同桌之間交換修改作文,請你修改你同桌寫的以下作文。文中共有10處語言錯誤,每句中最多有兩處。每處錯誤僅涉及一個單詞的增加、刪除或修改。

增加:在缺詞處加一個漏字符號(∧),并在其下面寫出該加的詞。

刪除:把多余的詞用斜線(﹨)劃掉。

修改:在錯的詞下劃一橫線,并在該詞下面寫出修改后的詞。

注意:1.每處錯誤及其修改均僅限一詞;

Agony Aunt,

I’m quite annoyed these days. It started from the last Wednesday. I lost a 100-yuan note in the classroom this morning. I asked my deskmate causally if he had seen it. To my great surprise, he burst into angry. “What do you mean by that?” asked him. “I am poor, so I’m never a thief!” I immediately explained, but he simply doesn’t listen. I knew he was too angry at the moment, so I decided to wait a day and two till he cooled down. But he didn’t give me time: the next day, he went to the teacher and asked never be my deakmate no more. Help me, Agony Aunt. How should I do?

Yours,

Li Hua

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】短文改錯(共10小題;每小題l分,滿分10分)

假定英語課上老師要求同桌之間交換修改作文,請你修改你同桌寫的以下作文。文中共有10處語言錯誤,每句中最多有兩處。每處錯誤僅涉及一個單詞的增加、刪除或修改。

增加:在缺詞處加一個漏字符號(),并在其下面寫出該加的詞。

刪除:把多余的詞用斜線(\)劃掉。

修改:在錯的詞下畫一橫線,并在該詞下面寫出修改后的詞。

注意:

1. 每處錯誤及其修改均僅限一詞;

2. 只允許修改10處,多者(從第11處起)不計分。

An old scientist recently made several tests with different animals to find out which was clever than other animals. In one test the old scientist put a monkey in the room where there was several boxes. Some boxes were inside other boxes. One small box have some food in it. The scientist wanted to watch the monkey and to find out how long it will take the monkey to find the food. The scientist left the room. He waited for a few minutes outside the door. Then he got down his knees and put his eyes to the keyhole. What did he see? To her surprise, he found himself looking at the eye of the monkey. The monkey was on the other side of the door and looks at the scientist through the keyhole.

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】短文改錯

假定英語課上老師要求同桌之間交換修改作文,請你修改你同桌寫的以下作文。文中共有10處語言錯誤,每句中最多有兩處,每處錯誤僅涉及一個單詞的增加、刪除或修改。

增加:在缺詞處加一個漏字符號(),并在其下面寫出該加的詞。

刪除:把多余的詞用斜線(\)劃掉。

修改:在錯的詞下畫一橫線,并在該詞下面寫出修改后的詞。

注意:

1. 每處錯誤及其修改均僅限一詞;

2. 只允許修改10處,多者(從第11處起)不計分。

Dear Diary,

Here I am in the middle of a city,350 miles far away from our farmhouse. Do you want to know why we move last week? Dad lost her job, and as Mom explained, "He is lucky to find other one." His new job meant I had to say goodbye to my classmate, my school and just everything else I love in the world. To make things bad, now I have to share a room to my younger sister, Maggie. Tomorrow is first day of school. I am very tiring, but I know I’ll never fall asleep. Good night, or remember, you is my only souvenir(紀(jì)念品) of my past life and my only friend.

Yours,

Rosemary

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】地處干旱區(qū)的寧夏銀川市,其周邊地區(qū)曾廣布湖泊,明清時有七十二連湖的說法。20世紀(jì)80年代銀川周邊湖泊所剩無幾。1999年開始,銀川實(shí)施恢復(fù)濕地的計劃。下圖示意銀川周圍目前的湖泊分布;卮鹣铝袉栴}。

120世紀(jì)80年代銀川周邊湖泊所剩無幾的主要原因是( )

A.泥沙淤積 B.氣候變暖 C.排水造田 D.黃河來水量減少

【2】疏浚、恢復(fù)湖泊濕地,對銀川環(huán)境的直接影響是( )

增強(qiáng)城市排污能力 增加城市空氣濕度 美化城市環(huán)境 增大城市氣溫年較差[m]

A.①② B.②③ C.③④ D.①④

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】 If you try to learn too many things at a time, you may easily get ______.

A. ashamed B. annoyed

C. confused D. embarrassed

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】After the deadly stampede(踩踏) in Shanghai, we can’t______ the importance of safety in public places too

much, particularly during holidays.

A. stress B. press

C. impress D. possess

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】Scientists are convinced ________ the positive effect of laughter ________ physical and mental health.

A. of; at B. of; on

C. by; in D. on; at

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】下圖為某日部分地區(qū)晝夜示意圖,陰影部分表示黑夜,其余部分表示白晝。讀圖回答問題。

1)按東、西半球劃分,圖上陰影部分主要位于____半球,此時甲地地方時是_______時。

2)按南、北半球劃分,此時太陽直射點(diǎn)位于_____半球,太陽直射點(diǎn)的經(jīng)度是________

3)該日乙地的白晝時間長約________小時。

4)如果這一天是農(nóng)歷十五,上海地區(qū)人們還需要等待約_______小時才能看到東邊天際升起的一輪圓月。

5)如果晨昏線與甲地所在經(jīng)線的夾角為10°,則該日正午時分上海(31°N)世博園場館的太陽能電池板與建筑物外墻面(墻面與地面垂直)之間最合適的夾角約為________

查看答案和解析>>

同步練習(xí)冊答案