Answer: Approximately 69.5 grams of gold (Au).
Explanation:
mol = mass / molar mass
We are already given the moles of gold, 0.353. Looking at a periodic table, we cna bserve that the approximate molar mass of gold is 196.97 (I got this from ptable.com).
Plugging this into the formula above, it will look like this:
0.353 mol Au = mass / (196.97 g/mol) (in any science class, do not forget about writing your units)
To get mass by itself, multiply both sides of the equation by 196.97 g/mol.
This yields that the mass is equal to 69.5 grams. As you can see, the units of "mol" cancel out: 0.353 mol AU * (196.97 g/mol)
The reason why I rounded my answer to 69.5 grams instead of, let's say, 69.5304, is because of a concept in science referred to as significant figures. In this case, the amount of significant figures we need to round our answer to is seen in the provided value in the problem. 0.353 has only three significant figures so I have rounded the final answer to three significant figures.
Remember, do not forget to not only unclude e units that answer should be in but some teachers also request that you write the symbol of the elemnt you are writing about, so I would write my answer as: 69.5 g Au.
I hope this helps :) have a nice day!
