Question

Which has more atoms: a 1-g sample of carbon-12 or a 1-g sample of carbon-13? explain?

Answer 1

From the Avogadro's constant  1 mole = 6.022 × 10^23 atoms
1g of Carbon-12 contains = 1/12 = 0.083 moles
Therefore; 0.083 moles × 6.022×10^23 
                 = 4.9983 × 10^22 atoms
1g of Carbon-13 contains = 1/13 = 0.077 moles 
                 = 4.6370 × 10^22 atoms
Therefore; Carbon-12 has more atoms than Carbon-13

Answer 2

Answer:

Carbon-12

Explanation:

Let's consider Avogadro's number: 1 mole of atoms has 6.02 × 10²³ atoms.

The molar mass of the isotope carbon-12 is 12 g/mol. The atoms contained in 1 g of ¹²C are:

$1g^{12}C.\frac{1mol^{12}C}{12g^{12}C} .\frac{6.02 \times 10^{23}atom ^{12}C}{1mol^{12}C} =5.0 \times 10^{22}atom ^{12}C$

The molar mass of the isotope carbon-13 is around 13 g/mol. The atoms contained in 1 g of ¹³C are:

$1g^{13}C.\frac{1mol^{13}C}{13g^{13}C} .\frac{6.02 \times 10^{23}atom ^{13}C}{1mol^{13}C} =4.6 \times 10^{22}atom ^{13}C$

There are more atoms in a 1-g sample of ¹²C than in a 1-g sample of ¹³C.