turning kg into joules do you use the units kilograms when working out an equation or would you convert them into g before using the equation

erm, you can't turn kg into joules, that's like turning lemons into bricks.

With equations, they are designed to take SI units, the SI unit for mass is kg, not g.

1J=1 kg \left({\frac {m} {s}}\right)^2

and the SI unit for joules is J so when both these terms are in the same equation I should leave Kg alone and not turn them into g sorry I should have phrased the question better, could you by any chance have a look at my other physics questions please

The SI unit for ENERGY is J. Yes you should leave it as kg :)

Nice one