What amount of pure acid must be added to 600 mL of a 40% acid solution to produce a 60% acid solution?

You need to add 300mL of a pure acid to produce a 60% acid solution.

Explanation:

Pure acid is a 100% acid. If you suppose X is the volume addition of the pure acid it is possible to write:

100%X + 600×40% = (600+X)60% (M₁V₁=M₂V₂)

100X + 24000 = 36000 + 60x

40X = 12000

X = 300

That means you need to add 300mL of a pure acid to produce a 60% acid solution.

I hope it helps!

the electronic configuration of an atom with eight electrons is 1s²2s²2p⁴. the orbital diagrams are shown in the figure.

as per the hunds rule:

1. electrons tend to avoid being in the same orbital as per as practicable.

2. electrons in different orbitals of the same energy will have their spin parallel.

this can be illustrated from the multiplicity of the orbitals of the atom. as there are four electrons in the p orbital and p orbital has 3 sub-shells. the electrons can be fed in different ways as shown in the figure but the correct orbital diagram will be as per the hunds rule.