Converting mass and capacity
Grams and kilograms measure mass. Millilitres and litres measure capacity. In both pairs, the big unit is 1 000 of the small one.
A worked example
Change 1.75 kg to grams. A gram is smaller, so multiply: 1.75 × 1 000 = 1 750 g. Change 2 500 mL to litres. A litre is bigger, so divide: 2 500 ÷ 1 000 = 2.5 L. Recap: kilo means 1 000 and milli means one thousandth, so every step is × 1 000 or ÷ 1 000.
The mistake people actually make
Mass and capacity measure different things. You cannot change grams to litres unless you know what the material is. Move the decimal point three places, not two.