The tablet has a mass of 1.20 g and contains 700 mg of lithium carbonate. Calculate the percentage by mass of lithium carbonate in this tablet.

The right answer is "58.3%".

Explanation:

The given values are:

Mass of lithium carbonate,

= 700 mg

i.e.,

= 0.7 g

Mass of tablet,

= 1.20 g

Now,

The percentage of active ingredient will be:

=  

On substituting the given values, we get

=  

=  

=  %

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons