Question

Is this Chemistry problem even possible?

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

One atom has a mass of 1.79E-23 grams.

One mole of atoms (molar mass) is 1.79E-23 * 6.02E23 = 10.7758 grams.

We're looking for an element that has an atomic mass of 10.7758. The element closest to that is Boron (B) with a mass of 10.81. The answer is boron.

#1

its simple., really.

so. 6.022 x 10^23 atoms in a mole right? so, you multiply the mass of one atom by Avogadro's Number, and you get...... 10.7758 g/mol, which is quite close to molar mass of B, boron.

BTW, is General Chemistry a college class>?

Love,

Le Docteur

#2

Is the molar mass of the element not 1.79e-23 grams * 6.0225e23 (number of atoms in a mole)?

This should give you the unit grams/mole or molar mass.

The equation amu=grams/mole can be used to find the amu of the element.

If grams = 1.79e-23 and moles = 1/6.0225e23, the amu should equal ~10.78 amu. This is very close to the amu of the element Boron.

Is there a flaw in this answer?

#3