How did he get 15 moles?

Question

What is the molarity of a 5.00 x 102 ml solution containing 2490 g of KI?

5.00*10^2ml = 500ml = .5L

KI has molar mass 166, so you have 15 moles of KI

15moles/.5L = 30moles/L = 30M

Answer 1

Given the reaction: Ni (s) + 4 CO (g)  Ni(CO)4 (g) E = –154 kJ, how many kilograms
of CO are required for this reaction to release 756 kJ of energy?

please

Answer 2

oops my bad. was gonna post new question, sorry i don't know the answer.