Question

Lithium stearate (octadecanoate) is made by neutralising stearic acid (octadecanoic

acid) with lithium hydroxide.
CH,(CH₂) 16COO Li* + H₂O
LiOH + CH,(CH₂) 16COOH
It is used as a component of low melting point greases that can be used down to
-60°C. In an experiment, 0-048 mole of stearic acid was neutralised by a lithium
hydroxide solution of concentration 0-64 mol dm
Calculate the volume of this lithium hydroxide solution needed to neutralise the
0-048 mole of stearic acid.
[2]
0.048 mole of
Stearic acid
Conc of LOH = 0.64 moi dm
-3
R = 1:1
:: 0.048 =
(1
clu
0.048
0.64
LOH Mole
=
0.075 dm-3
0.075

Answer 1

Step-by-step explanation:

Yes, that is correct. The formula weight of a compound is the sum of the atomic weights of all the atoms in the compound's chemical formula. To determine the percentage by mass of an element in a compound, you can use the molar mass of that element and divide it by the formula weight of the compound, then multiply by 100. In the case of a hydrated compound, the mass of the water molecules will dilute the percentage of the other elements, resulting in a lower percentage for the element of interest.