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Given: Solution:

H 2SO 4 Equivalent mass of sulfate
Al(OH) 3
acid: E acid =
Al 2(SO 4) 3
Its molar mass is equal
to determine:
М (H 2SO 4) = 2·1 + 32 + 4·16 = 98 g/molе
Е (H 2SO 4) – ?
Then:
Е (Al(OH) 3) – ?

Е (Al 2(SO 4) 3) – ?

E (H 2SO 4) = 98/2 = 49 g/mol equivalents.

Equivalent mass of aluminum hydroxide:

E bases =

The molar mass of Al(OH) 3 is:

M (Al(OH) 3) = 27 + 3 (16 + 1) = 78 g/mol. Then: E (Al(OH) 3) = 78/3 = 26
g/mol-eq.

To calculate the equivalent mass of aluminum sulfate, use the

formula: E salt =

The molar mass of Al 2(SO 4) 3 is:

M (Al 2(SO 4) 3) = 2 • 27 + 3 (32 + 4 • 16) = 342 g/mol.

Then: E (Al 2(SO 4) 3) = 342/2 • 3 = 57 g/mol-eq.

Answer:

E (H 2SO 4)= 49 g/mol-eq.,

E (Al(OH) 3) = 26 g/mol-eq.

Е (Al 2(SO 4) 3) = 57 g/mol-eq.

3
Example 5 How much mole is contained in 0.56 m of chlorine under normal
conditions?

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