Предмет: Химия, автор: menakbota

Срочно!!!!химияя 20балл
m(Mg) = 20г
m(MgO) =?

Ответы

Автор ответа: Alexei78
2

дано

2Mg+O2-->2MgO

M(Mg) = 24 g/mol

n(Mg) = m/M = 20 / 24 = 0.833 mol

n(Mg) = n(MgO) = 0.833 mol

M(MgO) = 40 g/mol

m(MgO) = n*M = 0.833 * 40 = 33.32 g

ответ 33.32 г

Автор ответа: Ilya27022002
1
Составим уравнение реакции:
20 г--------------х г
2 Mg + O2 = 2 MgO
---24--------------40
m (MgO) = (20 г * 2 * 40) : (2 * 24) = 33,33 г
Ответ: 33,33 г MgO
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Read the extract from the text and identify the appropriate meaning of the underlined word. 

Our body and health in the future

A. People always knew how their children would live. Now things are changing so quickly that we don’t even know what our lives will be like in a few years.

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C. New technologies will improve our health in the future and will play an important role in that. New medicines will help people get better. Robots will help doctors and sometimes replace them. They will diagnose and carry out operations, which will minimize the risk of mistakes. Scientists will find answers to many diseases and they will be cured in a very short time.

D. There will be less need for visits to the doctor. We will all have a home healthcapsuleand get regular check-ups that will tell us what the problem is and give us treatment. So, People will live longer for 100 or 120 years. Life will be much better in the future. Let’s hope so!

Robots will diagnose and carry out operations, which will minimize the risk of mistakes.

to make it bigger in size or amount, or more.

to move from a lower to a higher place or position.

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