Answer:
0.677 moles
Explanation:
Take the atomic mass of K = 39.1, O =16.0, P = 31.0
no. of moles = mass / molar mass
no. of moles of K3PO4 used = 4.79 / (39.1x3 + 31 + 16x4)
= 0.02256 mol
From the equation, the mole ratio of KOH : K3PO4 = 3 :1,
meaning every 3 moles of KOH used, produces 1 mole of K3PO4.
So, using this ratio, let the no. of moles of KOH required to be y.
y = 0.02256 x3
y = 0.0677 mol
If you don't find exactly 0.677 moles as one of the options, go for the closest one. A very slight error may occur because of taking different significant figures of atomic masses when calculating.
Explanation:
According to the law of the conservation of mass, 'mass is conserved in a chemical reaction. The mass cannot be created nor be destroyed in a chemical process'.
This law holds true for the burning of wood also. Although the wood burns to produce ash which weighs less than wood but also, it produces some soot and other gases and the sum of the masses of all these is equal to the sum of the masses of wood and oxygen that reacted with it.
<span>The two techniques for separating an insoluble solid from a liquid are filtration and centrifuging. Filtration relies on the fact that the solid particles are smaller than the filter paper pores which allow the tiny molecules of liquid to pass through. With solids which dissolve in a liquid solvent, evaporation is commonly used to recover the solid and distillation is used to recover the solvent.</span>
1- Molar solutions: based on number of moles of chemical in 1 litre of solution
2- Weight % solution: the weight of chemical divided by the total weight of the solution (chemical + water) and multiplied by 100.
