-
при взаимодействии 2,8 г оксида металического элемента второй группы с водой получилось 3,7 г гидроксида.Определите этот металический элемент.
Ответы 1
-
Формула оксидов металлов 2й группы : MeOMeO + 2H₂O ⇒Me(OH)₂ + H₂Пусть атомная масса металла будет равна x : Молярная масса (MeO) = 16 + xМолярная масса Me(OH)₂ = 34 + xnMeO = nMe(OH)₂ (исходя из уравнения реакции)nMeO = 2,8 / (16 + x)nMe(OH)₂ = 3,7 / (34+x)2,8 × (34+x) = 3,7 × (16+x)95,2 + 2,8x = 59,2 + 3,7x0,9x = 36x = 36 / 0,9x = 40Из 2 группы такую атомную массу имеет элемент кальцияОтвет : Ca
-
Автор:
atlasmtgc - 6 лет назад
-
0
-
-
Добавить свой ответ
Еще вопросы
- Два шара стальной массой 200 г и свинцовый массой 50 г подвешены на нитях в одной точке.Свинцовый шар отклоняют так,что он поднимается на высоту 20 см,и отпускают.После соударения он поднимается на высоту 10 см.Удар центральный.Определите количество энергии,перешедшее в тепло.
-
Составьте пересказ этого текста (10 предложений):
The Mad Tea Party
Alice looked around and saw the Cheshire Cat in a tree, with a big smile on its face.
“Excuse me,” she said, “can you tell me which way to go?"
“Where do you want to get to?" asked the cat.
“I don't know,” said Alice. “Where can I go?”
“A Hatter lives over there,” said the cat. He pointed one way. “And a March Hare lives over there." He pointed the other way. “You can visit either of them. They’re both mad."
“I don’t want to visit mad people," said Alice.
“Well, I’m sorry,” said the cat, "but we’re all mad here! I’m mad. You’re mad. Goodbye!"
The cat slowly disappeared, starting with its tail, until Alice could only see its smile.
“I’m going to visit the March Hare,” Alice said, and she walked through the wood until she came to the March Hare’s house.
When she saw the house, Alice knew* she was in the right place. There was fur on the roof, and the chimneys looked like long ears.
There was a long table under a tree in the March Hare's garden. The Hatter and the March Hare were at the table. There was a Dormouse between them. It was fast asleep.
Alice sat in one of the chairs. “Hello!" said the March Hare. “Have some lemonade!”
Alice looked at the table. There wasn’t any lemonade. There was only tea.
“I can’t see any lemonade," she said.
“There isn’t any,” said the March Hare.
"Then it was rude to offer it to me," said Alice.
"It was rude to sit down at my table,” said the March Hare. “I didn't invite you.”
“There are plenty of chairs." said Alice.
Nobody spoke* for a few minutes. Then the Hatter asked, "What day of the month is it?”
“It's the fourth,” said Alice.
The Hatter looked at his watch. “Two days wrong," he said to the March Hare. “I told you not to put butter in the watch.”
“It was very good butter," said the March Hare.
Alice looked at the watch. “How funny!” she said. “It tells the day of the month, but it doesn't tell the time.”
"Of course not!” said the Hatter. “Does your watch tell you what year it is?"
“No,” said Alice, "because the year stays the same for a long time.”
“Exactly!” said the Hatter. “Now, I want a clean cup! Let’s all move round the table!”
They all moved to the next seat. Now Alice had a dirty cup in front of her.
"I don’t think she said.
"Then don’t talk!" said the Hatter.
Alice was so angry that she walked away from the table. “What a stupid tea party!" she said.-
Предмет:
Английский язык -
Автор:
lolap2yx - 6 лет назад
-
Ответов:
0 -
Смотреть
-
-
Соня купила книгу за 20 €. На неё скидка 2%, потом ей дали ещё скидку 4%. Сколько она заплатит? Можно с решением)
-
Предмет:
Математика -
Автор:
morales38 - 6 лет назад
-
Ответов:
2 -
Смотреть
-
-
Расставьте запятые, пожалуйста
В первой части текста учитель пытается донесnи до детей мысль о том что если люди объединятся, они способны на многое.-
Предмет:
Русский язык -
Автор:
phoebe40 - 6 лет назад
-
Ответов:
4 -
Смотреть
-
Топ пользователей
-
Fedoseewa27
35934 -
Askold
2792 -
Pikachu
2228 -
hobbesbowers
2116 -
kaylynnbarron676
1818 -
女fei
1240 -
yulia-kaplina
1158 -
Poinntt
946 -
Bars
930 -
Queenmagic18
770
How much to ban the user?
1 hour
1 day
100 years