请认真阅读下面各小题，并根据提示写出正确的单词。

小题1:I have to believe that encouragement is so _____________ (强有力的) that it can change a person.

小题2: I’m g___________(感激的) to my teachers’ help.

小题3:I’ve known Lucy for years. __________(实际上)，we have been good friends since our childhood.

小题4:The people ___________(受伤) in the accident were sent to hospital without delay.

小题5: Every year, many natural ___________(灾难) happen all over the world.

小题6:Lucy! I’m sorry I didn’t r___________ you. You’ve had your hair cut.

小题7:Father is thankful to me for p____________ him to give up smoking.

小题8:Some people hold a wrong a___________ towards the disabled.

小题9:She refused to give the taxi f________ because of the delay.

小题10:He b________ into tears at the news that both of his parents died in the Yushu earthquake.

+2价金属元素M的原子中质子数比中子数少2个，2.1g的单质M与足量的盐酸反应 * * 生氢气0.05mol．试通过计算确定：

（1）该元素的摩尔质量为______g/mol，

（2）用

形式表示上题中金属元素M的原子______．