Question

How do I solve this problem? What steps do I need to do to solve this question? It asked on paper, "You place a piece of paper on a balance and find that its mass is 0.63 g. You add a lump of NaOH to the paper and get a mass of 22.21 g. How Much NaOH do you have on the balance, in grams, milligrams, micrograms and kilograms?"
How do I solve milligrams, micro and kilogram using 22.21 grams and 0.63? do I subtract??

Answer 1

Seriously do i just subtract or what? what am i suppose to do?
someone answer grams but it wasn't explain how they got the answer

Answer 2

Yes, subtract
22.21 g = mass paper + mass NaOH
- 0.63 g = mass paper
-----------------------------------
21.58 g = mass NaOH
(You will note that 22.21-0.62 is the 21.58 g. When you subtract mass paper from mass paper you get nothing. When you subtract mass NaOH - zero you get mass NaOH. So the next lined reads 21.58 g = mass NaOH.
Now convert 21.58 g to the other units. I'll do one for you; i.e., from grams
to kg. In your text or notes you will find that there are 1000 g in 1 kg so
21.58 g x (1 kg/1000 g) = 0.02158 kg
I shall be happy to check your other calculations. This is not rocket science so don't be discouraged.