Предмет: Химия, автор: kurowll

Помогите! Обчислити відносну густину за повітрям газів з такими формулами:SO3, C2H6, SiH4

Ответы

Автор ответа: unezhewaoxnw6u

3

Объяснение:

D= M(SO3)/M(повітря)=(32+3•16)/29 = 80/29 = 2.76

D= M(C2H6)/M(повітря)=(2•12+6•1)/29 =30/29 = 1.03

D= M(SiH4)/M(повітря)=(28+4•1)/29 = 32/29 = 1.10

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Предмет: Английский язык, автор: melonforschool20

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Complete the sentences with the correct form of
the adjectives given.
1 A mouse is …………………………..…... (small) than an
elephant.
2 Science is …………………………..…... (easy) than history.
3 Your car was …………………………..…... (expensive) than
hers.
4 His house is …………………………..…... (near) than mine.
5 Fruit is generally …………………………..…... (healthy) than
chocolate.

/ 5
2 Complete the sentences with the correct form of
the adjectives given.
1 The Blue Planet is …………………………..…... (interesting)
nature programme I’ve ever seen.
2 Ali is…………………………..…... (heavy) person in our family!
3 George is …………………………..…... (strong) person I know.
4 I think Messi is …………………………..…... (good) footballer in
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5 I think people are …………………………..…... (dangerous)
animals in the world.

3 Complete the sentences with the present perfect
form of these verbs. There are two extra verbs.
climb • go • help • meet
not visit • see • wear

1 …………………………..…... you ever …………………………..…... a
mountain?
2 She …………………………..…... lots of famous people.
3 They …………………………..…... never …………………………..…...
me with my homework.
4 …………………………..…... he …………………………..…... the new
James Bond film?
5 I …………………………..…... the Eiffel Tower.

6 Choose the correct alternatives to complete the
text.
Cows are big animals with four (1) legs/horns. They don’t
have toes on their (2) heads/feet – they have hard
‘hooves’. Sometimes they have two (3) wings/horns on
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Total / 15

Use of English
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