Answer: 50. 4g
Explanation:
First calculate number of moles of aluminium in 38.8g
Moles = 38.8g/ 26.982mol/g
= 1.44mol
By looking at the balance equation you can see that 4 moles of aluminium produce 2 moles of aluminium oxide.
4 = 2
1.4 = x
Find the value of x
x= (1.4×2)/4= 0.72 mol
0.72 moles of aluminium oxide are produced from 38.8g of aluminium
Now find the mass of aluminium produced.
Mass = moles × molar mass
= 0.72mol × 69.93 mol/g
= 50.4g
Answer:
A buffer solution is a mixture of two pair salts to maintain a stable pH.
Explanation:
This mixture is made always with a complementary pair of salts (one acid an another basic).
Example:
Acetic Acid (CH3COOH) and Sodium Acetate (NaH3COO).
So when you add a little bit more acid to this mixture, the basic part of the buffer, in this case the Sodium Acetate, will neutralize it and the pH will remain the same.
On the other hand, if the mixture receives some basic substance, the acid part of the buffer, the acetic acid, will neutralize it, so again the pH will remain the same.