can someone help me rewrite my science sentences to a better one and using therefore after however like those stuff conjunctions THIS IS FOR SCIENCE

Tin has ten stable isotopes. the heaviest, 124sn, makes up 5.80% of naturally occuring tin atoms. how many atoms of 124sn are present in 82.0 g of naturally occurring tin? what is the total mass of the 124sn atoms in this sample?

Write the balanced equation for a reaction between aqueous nitric acid (hno3) and solid lithium metal (this is a single replacement reaction)

What is the compound name for the formula [ru(en)2cl2]2+ and [co(en)cl2br]-