Предмет: Химия, автор: sofiya2960

Краткий очерк истории развития химии

Ответы

Автор ответа: безумнаявкедах

5

Зарождение науки о веществах можно отнести к эпохе античности. Древние греки знали семь металлов и еще несколько сплавов. Золото, серебро, медь, олово, свинец, железо и ртуть – вот вещества, которые были известны в то время. История химии началась с практических знаний. Их теоретическое осмысление было впервые предпринято различными учеными и философами – Аристотелем, Платоном и Эмпедоклом. Первый из них считал, что каждое из этих веществ может преобразовываться в другое. Он объяснял это существованием первоматерии, которая послужила началом всех начал.

Приложения:

Предыдущий вопрос

Следующий вопрос

Похожие вопросы

Предмет: Українська мова, автор: sofiamitisevska

у якому рядку всі слова дієприслівники недоконаного виду а) пишучи,намалювавши,носячи,пішов б)кажучи,сміючись,заплакавши,переходячи в)лежачи,корегуючи,тримаючи,друкуючи г)сидівши,лежачий,натрмившись,передаючи поможіть благаю

6 лет назад

Предмет: Английский язык, автор: Gulnazcom25

Дайте пожалуйста ответы на эти задания.
22 Joe’s fear of enclosed spaces __________ from a bad experience he had when he was a child.
a) stems
b) leads
c) starts
d) dreams
23 At the moment _______________ to play the guitar.
a) I’m learning
b) I learn
c) I’ll learn
d) I’d learned
24 My course finishes_____________.
a) on next week
b) next week
c) at next week
d) to next week
25 The train ________________ at 9.30.
a) leaves
b) it leaves
c) leaving
d) is leaving
26 Where ________________ those shoes?
a) you buy
b) did you buy
c) does you buy
d) do you buy
27 I’ve worked at this company ____________ two years.
a) since
b) for
c) at
d) on
28 Can you tell me what time _________________?
a) does the train leave?
b) the train leaves?
c) the train will leave?
d) the train will be leave?
29 England is not __________ big as Germany.
a) so
b) as
c) as so as
d) too
30 There was a terrible plane crash – it ________________ an hour ago.
a) happened
b) has happened
c) has been happened
d) is happening
31. Adrian is a very good friend of ____________.
a) me
b) my
c) mine
d) I

32. Helena’s not really a party animal, so I doubt whether she__________ .
a) comes
b) will come
c) will have come
d) come
33. I was wondering if you _________________ to go running with me.
a) wanted
b) had wanted
c) would want
d) will want
34. She _______ hate washing up, but now she likes it.
a) was used to
b) use to
c) used to
d) is used to

35. The noise stopped as soon as the Head Teacher ________ into the room.
a) walks
b) walked
c) was walking
d) will walk
36. How long ____________________ these pills?
a) did you take
b) are you taking
c) have you been taking
d) do you take
37. No, I ____________________ possibly do that to a friend.
a) mustn’t
b) shouldn’t
c) couldn’t
d) may not
38. Well I’m surprised it was John. I _____________ have expected better of him.
a) would
b) could
c) should
d) can
39. Don’t worry about my big brother; he ____________ be very childish at times.
a) will
b) can
c) could
d) must
40. I really ______________ eat another thing, thank you.
a) wouldn’t
b) couldn’t
c) mightn’t
d) may not
41. You ______________be serious! It’s far too dangerous!
a) couldn’t
b) can’t
c) mustn’t
d) may not
42. This little device ________________ be the answer to all your technical problems.
a) need
b) could
c) shall
d) must
43. What you’re saying ___________ well be true.
a) must
b) should
c) may
d) have to
44. Just in case you ____________ _____ it, I’ll give you my business card so you can contact me.
a) would find
b) will find
c) find
d) can find
45. Climbing in the Himalayas was a far ___________ from hill walking at home in Ireland.
a) shout
b) scream
c) cry
d) call
46. My bike isn’t what you would call fast or sporty, but it serves its ________.
a) purpose
b) aim
c) reason
d) intention
47. Rest assured that we have taken every possible safety ________________.
a) protection
b) preparation
c) precaution
d) action
48. They sell all sorts of household ______________: washing machines, dishwashers and so on.
a) machines
b) mechanisms
c) appliances
d) gadgets
49. After just ten minutes in the rain, I was______________ to the skin.
a) damp
b) wet
c) soaked
d) slopped
50. ‘Sorry Mrs. Atkins. I wasn’t _____________ attention,’ said Billy.
a) giving
b) paying
c) keeping
d) having
51. Every morning I see kids from the local school____________ football down by the river.
a) taking
b) enjoying
c) playing
d) running
52. John and Mary, come over here. Have you two met___________ before?
a) yourselves
b) each other
c) together
d) themselves

53. It’s quite expensive, but__________ the other hand it’s very good quality.
a) on
b) by
c) in
d) at

54. ____________ he is, he shouldn’t behave like that.
a) No matter
b) Whoever
c) At once
d) Who

6 лет назад

Предмет: Английский язык, автор: danaleniv09

Дам 50 балів ......

6 лет назад

Предмет: Информатика, автор: natalipolyacko

Выделите имя и расширение.Что можно сказать о типе файла.
самостоятельная работа.doc самостоятельная работа.jpg

9 лет назад

Предмет: Алгебра, автор: chizh021

Сократите дробь
ax-2a/ax

9 лет назад