Number of moles = mass of Ni /molecular mass of Ni
mass of nickel = 86.4 g
molecular mass of nickel = 58.69
number of moles of Ni in 86.4 g
=86.4/58.69
=1.472 mol
(rounded to four significant figures instead of three because the first digit of the answer starts with a 1).
The expression for the Ka for the given acid is:
Ka = [H2P2O7^2-] [H3O+] /[H3P2O7^2-]
<span>Ka is the acid dissociation constant or the acidity constant. It is a measure of the acid strength when in solution. It is an equilibrium constant for the dissociation of the acid.</span>
Because the speed of light is determined by the medium that is it in. If light is in a vacuum it goes 300 million meters per second but it is slower in air, and even slower in water because water is more dense than the previous two.
Well you know that you have to balance out the equation to 0. So if I is -1 and Ca is +2 you know that I had to equal to -2. So you can do that by having two of them. So Ca=+2 and I2=-2 so CaI2 would equal 0 meaning that would be the correct answer. Hope that I explained that correct :)
Option C: The dissociation of a polar covalent compound in water.
Sugar is made up of sucrose molecules containing polar covalent bonds. They have same type of oxygen-hydrogen covalent bonds that are present in water.
Since, sugar is not an ionic compound, option a and option b are incorrect. Also, due to same type of bonding in water and sugar molecules there will be no such force of attraction between them, this will opt out the option d.
Thus, dissolution of sugar in water is the dissociation of a polar covalent compound in water and option c is correct.