Which of the following is not the same as 2.97 milligrams?
a)0.297 cg
b)0.00297 g
c) 0.297 kg

Answer : The (C) 0.0000297 kg is not the same as 2.97 mg.

Explanation :

The conversion used for mass from milligram to centigram is:

The conversion used for mass from milligram to gram is:

The conversion used for mass from milligram to kilogram is:

As we are given that the mass 2.97 mg. Now we have to determine the mass in cg, g and kg.

Mass of 'cg' :

Mass of 'g' :

Mass of 'kg' :

Hence, from this we conclude that, 0.0000297 kg is not the same as 2.97 mg.

1.solid

2.carbon dioxide

3.helium

the formula mass of a molecule or a compound is the sum of the atomic weights of the atoms in its empirical formula

(that's what i know about formula mass)