Question

How to find the molar mass of an unknown element based of mass?

Heres the question from my General Chemistry Class.

10. One atom of an unknown element (monatomic) is found to have a mass of 1.79 * 10^-23 grams, what is the molar mass (specify units) and identify the element.

I checked my lecture but I can't find any formuals to solve molar mass based off the mass alone without the element's atomic mass. Am I missing something in the question or is it impossible. Please solve if it's possible. Thanks.

Answers

Molar mass is is the amount of grams in 1 mole of the substance. 1 mole of any given substance contains 6.23 x 10^23 atoms.

So we know that 1 atom contains 1.79 x 10^23 grams, right? And we need to find out how many grams are in 1 mole, or 6.23 x 10^23 atoms.

So, to find this out, we will multiply 1.79 x 10^-23 grams by 6.23x10^23. atoms.

(1.79 x 10^-23) x (6.23 x 10^23) = 11.1517 grams

So the molar mass is 11.1517 grams.

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