题目内容

【题目】根据元素周期表1~20号元素的性质和递变规律,回答下列问题:

1属于金属元素的有 种,其中金属性最强的元素的单质与氧气反应生成的化合物的化学式为 填两种

2最高正化合价最高的元素是 填元素符号,其最高正化合价为

3单质既能与HCl反应,又能与NaOH反应的是 ,其最高价氧化物对应的水化物具有 填“酸性”“碱性”或“两性”

4第三周期中,原子半径最大的元素是稀有气体元素除外

5比较Si、N最简单氢化物的稳定性: 用化学式表示

【答案】17;K2O、K2O2KO2也可以

2Cl;+7价

3Al;两性

4Na

5NH3>SiH4

【解析】前20号元素中,1属于金属元素的共有7种,其中金属性最强的元素是钾,钾单质与氧气反应生成的化合物有K2O、K2O2、KO2;2最高正化合价最高的元素是Cl,其最高正化合价为+7价;3既能与HCl反应又能与NaOH反应的单质是铝,其最高价氧化物对应的水化物是AlOH3,具有两性;4同一周期从左往右,原子半径逐渐减小,故第三周期中,原子半径最大的是Na;5非金属性:N>P>Si,故NH3的稳定性大于SiH4的稳定性。

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【题目】七选五

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Building Trust in a Relationship Again

Trust is a learned behavior that we gain from past experiences. ____1____ Trust is a risk. But you cant be successful when theres a lack of trust in a relationship that results from an action where the wrongdoer takes no responsibility to fix the mistake.

Unfortunately, weve all been victims of betrayal. Whether weve been stolen from, lied to, misled, or cheated on, there are different levels of losing trust. Sometimes people simply cant trust anymore. ____2____ Its understandable, but if youre willing to build trust in a relationship again, we have some steps you can take to get you there.

____3____ Having confidence in yourself will help you make better choices because you can see what the best outcome would be for your wellbeing.

____4____ If youve been betrayed, you are the victim of your circumstance. But theres a difference between being a victim and living with a victim mentality. At some point in all of our lives, well have our trust tested or violated.

You didnt lose everything. Once trust is lost, what is left? Instead of looking at the situation from this hopeless angle, look at everything you still have and be thankful for all of the good in your life. ____5____ Instead, its a healthy way to work through the experience to allow room for positive growth and forgiveness.

A. Learn to really trust yourself.

B. It is putting confidence in someone.

C. Stop regarding yourself as the victim.

D. Remember that you can expect the best in return.

E. Theyve been too badly hurt and they cant bear to let it happen again.

F. This knowledge carries over in their attitude toward their future relationships.

G. Seeing the positive side of things doesnt mean youre ignoring what happened.

【题目】七选五

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项,选项中有两项为多余选项。

Encouraging your high school student to do his/her best isnt as hard as you may think. It does take time and effort, but it should become part of a daily routine that both you and your teen can enjoy more than dread(担忧). Here are some tips that can help you.

1. 1 Know what classes he/she is taking, what your teen thinks of the teacher and/or ask if your teen feels he/she is learning anything. This is excellent dinner table conversation if you can keep it light and positive.

2. Set the expectations. 2 You would not do your teen any favors by not telling him/her what grades you will be expecting. Send a clear message to your teen about the grades you expect to see in each class. ____3____ Keep your expectations in line with what your teen feels he/she can do.

3. 4 While your teen will need to keep his/her goals in line with your expectations, he/she may have a goal that he/she feels is important too. Learning to establish goals teaches independence, one of the things your teen needs to learn to become a successful adult.

4. Have what they need at home, or a way to get it. 5 Your family should have library cards and a way to access the Internet for homework. Without these things, your teen could be at a disadvantage. It is also a good idea to set up a mobile homework center.

Finally, dont forget to praise your teen for a job well done.

A. Help him/her establish goals.

B. Talk to your teen about school.

C. Learning in a classroom is a two-way street.

D. Resources are important for high school students.

E. Teens need a clear map of what you want them to do.

F. Set a good example and show him/her your love of learning.

G. Set consequences for poor grades as well as rewards for good grades.

【题目】A

阅读下短文从每题所给的A、B、C和D四个选项中选出最佳选项。

DOGS DRIVE CAR

Auckland, New Zealand

After two months of learning, Monty, and Porter were able to drive an automobile around a racetrack. We wanted to prove how smart rescue dogs are, animal behaviorist Mark Vette says. Vette first used voice commands and treats to teach the dogs how to turn a steering wheel and how to change gear (换挡).

The dogs ride only accelerated up to 7.5 miles an hour, and trainers could stop the auto using a remote control.

GOLDEN ZEBRA

Kailua-Kona, Hawaii

Zoe the zebras markings are special. The animal has white and golden stripes. Zoes appearance resulted from a rare condition called amelanosis (黑素缺失症). Her body doesnt make enough melanin(黑色素), the substance in an animals skin and hair cells that produces color. Only 25 other golden zebras are known to exist in the world, says Ann Goody, who runs the wildlife refuge where Zoe lives. In the wild, life may be difficult for animals with amelanosis because predators (捕猎者) can easily spot them. But Zoe is protected at her refuge.

COCKATOO MAKES TOOLS

Vienna, Austria

When Figaro the cockatoo spots food lying just out of reach from his cage, he builds a tiny wooden tool to sweep the tasty prize in his way.

The bird first revealed his talent when a stone he was playing with rolled out of his cage. The cockatoo couldnt reach the stone. So he flew away and returned with a small branch, slipping it through the fence to slide the stone toward him.

Wondering if he would do it again, scientists placed a nut exactly where the stone had been. This time, Figaro pulled out a small piece of wood in his cage and dragged the nut toward him.

【1】 If Zoe the zebra is set free in the wild, she will ___________.

A. meet no natural predators

B. not get along with other zebras

C. manage to make enough melanin

D. be easily found for her appearance

【2】Whats special about Figaro the cockatoo?

A. He is particular about his food.

B. He is extremely fond of stones.

C. He is good at drawing support from outside forces.

D. He can tell the difference between stones and nuts.

【3】What is the text mainly about?

A. Amazing animals.

B. Ways to help animals.

C. Animals unique talents.

D. Tips on training animals.

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