The only danger is that you may end up thinking that chemistry is simply a math problem - which it definitely is not. Set up each problem by writing down what you need to find with a question mark. Then set it equal to the information that you are given. The problem is solved by multiplying the given data and its units by the appropriate unit factors so that only the desired units are present at the end. You can also string many unit factors together.
Scientists generally work in metric units.
We also can use dimensional analysis for solving problems. 1 molecule of NH 3 has 3 atoms of hydrogen in it. The volume of a wooden block is 6.30 in 3 .