Answer:
0.307 mol
Explanation:
From the given question above, we are trying to obtain the number of mole.
The data obtained from the question include:
Molarity (M) = 0.768 M = 0.768mol/L
Volume (V) = 0.400 L
Number of mole =?
Molarity is simply the mole of solute per unit litre of the solution. It is represented mathematically as:
Molarity(M) = number of mole (n)/Volume(V)
M = n/V
If make n the suject of the formula by cross multiplying, we'll have n to be:
n = MV
Now, imputing the values of M and V from the question, we obtained:
n = 0.768mol/L x 0.400 L
Notice how the unit will cancel out i.e 'L' will cancel out 'L' leaving 'mol' as the standing unit
n = 0.307 mol