Question #170268

Which sample contains the same number of atoms as 24 grams of carbon? (1) 10. g Ne (2) 24g Mg (3) 80. g Ar (4) 4.0 g He (Can you explain or write it out please)

Expert's answer

M(C) = 12 g mol^{-1};

M(Ne) = 20 g mol^{-1};

M(Mg) = 24 g mol^{-1};

M(Ar) = 40 g mol^{-1};

M(He) = 4 g mol^{-1}.

**Solution:**

One mole of any substance contains 6.022×10^{23} atoms/molecules (N_{a}).

Hence,

Number of atoms in 24 g of C = (24 g / 12 g mol^{-1}) × N_{a} = 2.0 × N_{a} atoms

(1): Number of atoms in 10 g of Ne = (10 g / 20 g mol^{-1}) × N_{a} = 0.5 × N_{a} atoms

(2): Number of atoms in 24 g of Mg = (24 g / 24 g mol^{-1}) × N_{a} = 1.0 × N_{a} atoms

**(3): Number of atoms in 80 g of Ar = (80 g / 40 g mol**^{-1}**) × N**_{a}** = 2.0 × N**_{a}** atoms**

(4): Number of atoms in 4 g of He = (4 g / 4 g mol^{-1}) × N_{a} = 1.0 × N_{a} atoms

Hence, **(3)** (80 grams of argon) contains same number of atoms (2N_{a} atoms) as in 24 grams of carbon.

**Answer: 80 grams of argon (Ar) contains same number of atoms (2.0 × N**_{a}** atoms) as in 24 grams of carbon (C).**

Learn more about our help with Assignments: Chemistry

## Comments

## Leave a comment