题干

分子是构成物质的一种微粒,分子很小,无法用肉眼直接观察.某同学通过以下实验得到的有关对分子的认识,正确的是(   )

A:蔗糖颗粒溶解在水中后不见了,说明蔗糖是由分子构成的

B:黄豆与芝麻混合,混合后的总体积小于混合前的总体积,说明分子之间有间隔

C:将红墨水小心注入热水中,过一会儿整杯水变红色,说明温度越高,分子运动越快

D:抽去玻璃板,过一会儿两瓶都变红棕色,说明分子在不断地运动

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D

同类题4

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    People often say that the Englishman's home is his castle. They mean that the home is very important and personal to him. Most people in Britain live in houses rather than flats, and many people own their homes. This means that they can make them individual(个体的): they can paint them, and change them in any way they like. Most house have a garden, even if it is a very small one, and the garden is usually loved. The house and the garden are the private(私人的) space of the individual.

    People usually like to mark their space. Are you sitting now in your home or on a train? Have you marked the space around yourself as yours? If you are on the train you may put your coat or small bag on the seat beside you. If you share a flat you may have one corner or chair which is your own.

    Once I was travelling on a train to London. I was in a section for four people and there was a table between us. The man on the space on my side of the table didn't notice me at all. I was angry. Maybe he thought that he owned the whole table. I had read a book about non-verbal communication, so I took various papers out of my bag and put them on his briefcase! When I did this he stiffened and his eyes nearly popped(瞪出) out of his head. I had invaded(侵犯) his space! A few minutes later I took my papers off his case in order to read them. He immediately moved his case to his side of the table. Of course, it is possible that he just wanted to be helpful to me!

    If you are visiting another country you may feel that you don't have any private space. Hotel rooms look much the same in every country in the world. All day long, you share public spaces with other people. You see the local people in their private spaces and you feel lonely and "outside". Local people can create their private spaces by talking about things you don't know about. And you even feel that they like you to be outside them so that they will enjoy being inside even more! This is one of the difficulties of being a traveler! But if you understand it then it helps you. Haven't you enjoyed being part of a group and "owning" a bit of space?