5. Compound A has a MW of 283. 0.423g of Compound A is dissolved in 13.5mL of water and 1mL of the solution added to 5mL of water to produce “solution A”. What is the concentration of Compound A in “solution A”?

Answer 1

You should specify the units of concn. g/L, g/mL, M, etc.
If you want molarity, then
0.423/283.0 = moles.
moles/0.135L = M of the original.
M x 1mL/5mL = new M.