Question

Calculate: The number of atoms in 11.5g of sodium.​

Answer 1

Answer: 3.011 * 10^23 atoms

Step-by-step explanation:

Molar mass of Na=23g/mol

no. of moles = weight/molar mass

n = 11.5/23

no. of moles = 0.5

no. of moles = no. of atoms/avogadro’s number

0.5 = no. of atoms/6.022*10^23

0.5*6.022*10^23 atoms = no. of atoms

3.011*10^23 atoms.

So there are 3.011*10^23 atoms present in 11.5g of sodium sample.

Hope this helps!!! :)

Answer 2

The number of atoms in 11.5 g of sodium is 0.501 x 6.022 x 10^23 atoms/mol = 3.015 x 10^23 atoms.

Step-by-step explanation:

To calculate the number of atoms in a given mass of a substance, you first need to know the atomic mass of the element in question. The atomic mass of sodium is 22.99 g/mol. This means that 11.5 g of sodium contains 11.5 / 22.99 = 0.501 mol of sodium atoms.

Since the atomic mass of sodium is known, we can now use the formula for the number of atoms, which is given by Avogadro's number. Avogadro's number is a constant that represents the number of atoms in one mole of a substance, and it has a value of 6.022 x 10^23 atoms/mol.

Therefore, the number of atoms in 11.5 g of sodium is 0.501 x 6.022 x 10^23 atoms/mol = 3.015 x 10^23 atoms.