Question

How many moles of atoms are in 7.00 g of 13c? express your answer numerically in moles?

Answer 1

There are 0.538 moles of ¹³C atoms in the given 7.00 g sample.

Further Explanation

This is a simple mole conversion problem.  It requires the molar mass, or the mass of one mole of a substance, of carbon - 13, an isotope of carbon. An isotope is like a different version of a specific atom. In this case, carbon - 13 is a version of a carbon atom that has one more neutron than the normal carbon atom. It is a little heavier than the normal carbon atom because of its extra neutron.

Converting Mass to Moles

To convert from grams of sample to moles of sample, the general equation is:

$moles \ of \ sample = \frac{given \ mass}{molar \ mass}$

To convert 7.00 g of ¹³C, the equation is:

$mole \ of \ ^{13}C \ = \frac{7.00 \ g}{13.00 \ \frac{g}{mol}} \\\boxed {mole \ of \ ^{13}C \ = 0.53846 \ mol}$

Since there is only 3 significant figures in the given, the final answer must also have 3 significant figures. Therefore,

$\boxed {\boxed {mole \ of \ ^{13}C \ = 0.538 \ mol \ or \ 5.38 \times 10^{-1} \ mol}}$

This answer is logical since one mole of ¹³C will have a mass of 13.00 g. The given sample (7.00 g) is less than 13.00 g so the mole equivalent of that should be less than one mole.

Learn More

1. mole conversion  brainly.com/question/12980009
2. stoichiometry brainly.com/question/10513747

Keywords: moles, molar mass

Answer 2

Molar mass of 13c = 13 grams
number of moles = mass / molar mass
therefore,
number of moles = 7 / 13
To know the number of atoms in 7/13 moles, we simply multiply the number of moles by Avogadro's number as follows:
number of atoms = (7/13) x 6.022 x 10^23 = 3.2426 x 10^23 atoms