Предмет: Химия, автор: 03MaryBarry03

1) Ca(NO3)2
W(N)-?
2) m(MgO)=40г
m(Mg)-?
Очень Срочно!!!!!!!!!

Ответы

Автор ответа: 3060XLXO
1

Здравствуй 03MaryBarry03!

Не буду много писать, а сразу приступлю к делу:

1)Дано:

Ca(NO3)2

W(N)-?

Решение:

1. Вычислим относительную молекулярную массу нитрата кальция:

Mr (Ca(NO3)2) = 40 + 14 * 2 + 3 * 2 * 16 = 164

2. рассчитаем массовую долю азота (N) в соединении:

w (N) = 2 * Ar (N) : Mr (Ca(NO3)2) = 28 : 164 = 0,1707 или 17,07%;

2) Дано:

m(MgO)=40г

m(Mg)-?

Решение:

1. m= M*n

Чтобы найти m, нам для начала нужно найти М, и затем n

M (MgO) = 24+16 = 40

2. n= m/M = 40/40= 1

3. m= M*n = 40*1=40

Надеюсь что я решил все верно, хотя есть сомнения насчет 2 задачи, удачи в последующих решениях!

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