Предмет: Химия, автор: KimHad

Дополните предложения:
(а) Замерзание воды в стакане это явление___________________, потому что ______________________________________________________________
(б) Взаимодействие медного купороса с щелочью это____________ явление , потому что___​

Ответы

Автор ответа: ChristineVI
2

Ответ:

(а) Замерзание воды в стакане это явление физическое, потому что меняется физич.свойство вещества (агрегатное состояние).

(б) Взаимодействие медного купороса с щелочью это химическое явление , потому что при этом происходит образование нового вещества (выпадает голубой осадок).

Объяснение:

Физическими явлениями называют те, при которых не происходит превращение одних веществ в другие.

Пример - испарение воды или замерзание, плавление стекла, засахаривание варенья, запах духов.

Т.е мы можем сделать вывод, что при физических явлениях могут изменяться физич. св-ва вещества: температура, агрегатное состояние, плотность и т.п

Химическими явлениями называют те, при которых происходит превращение одних веществ в другие (образование нового вещества/двух веществ)

Пример - горение древесины, гниение листьев, коррозия металлов (ржавление) и т.п

Т.е мы можем сделать вывод, что при химических явлениях происходит изменение состава и строения веществ.

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UNDER THE HIGH TREES
It was six o’clock when Ben Smith, dreadfully tired, arrived home from the school where he was a teacher. He had had a lot of work and trouble that day. He dreamed of a quiet evening at home. June, his wife, met him at the door similing radiantly. She asked Ben to be quick with his supper and change clothes after that. She said she had got everything arranged and they would go to the theatre.
Only then did Ben remember it was the very night that had been settled for their going out. So June was realizing her dream. He envied his daughter Penny, a sixteen-year old girl, who said she would stay indoors and watch television. But suddenly he was sorry for June who got too little entertainment even at week-end.It was already past seven when they started for the theatre. The weather was unusually nasty. Ben's nose and feet were cold. After 20 minutes a number 64 bus stopped.
They got on, but the seats were full. Unfortunately the bus conductor told Ben to get off as only seven people could stand in the bus. Ben did so forgetting that his wife had got the tickets.

It was pouring now. The road was wet and there was a hole in his shoe. Luckily he got on the next number 64 bus soon enough and found a seat. Ben shut his eyes. When he opened them again, the bus was past the theatre. It was still raining as he walked back to it feeling unhappy. Over the doors were the words, "Under the High Trees".
The man at the door said he could not let him in without a ticket. Ben was about to leave when a girl behind the ticket-office window said: "Are you Mr. Smith? Your wife left your ticket with me."
Ben squeezed to his seat in the dark, stepping on people's feet. He asked June what the play was about. She whispered she could not understand much as one actor, an old man, spoke very quietly, and the other, the young man, spoke very quickly.
As soon as the play was over, they ran out. There were no buses and it was still raining. They waited and waited and their clothes got wetter and wetter. At last Ben lost his patience and shouted: "Taxi!"
A passing taxi stopped. Ben pushed his wife in. "Two pounds," said the driver when they arrived.”What?" "After ten o'clock in the evening the fare is higher."
Unwillingly Ben paid the driver. Besides all the trouble it turned out to be too expensive to them.
"Did you watch television, Penny?" Ben asked his daughter.
"Yes," she said. "You can't imagine how brilliant the play was."
"What was the name of it?" asked Ben as he picked up his cup of coffee.
"Under the High Trees" was the answer. Ben Smith put his cup of coffee on the kitchen table and went slowly upstairs to bed.
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