How many sodium atoms are present in one mole of sodium chromate [tex](Na_2 CrO_4)[/tex]?

A. [tex]6.0 \times 10^{23}[/tex] atoms
B. [tex]4.2 \times 10^{24}[/tex] atoms
C. [tex]1.2 \times 10^{24}[/tex] atoms
D. [tex]2.4 \times 10^{24}[/tex] atoms



Answer :

To determine how many sodium atoms are present in one mole of sodium chromate (Na[tex]\(_2\)[/tex]CrO[tex]\(_4\)[/tex]), follow these steps:

1. Identify the Number of Sodium Atoms in One Molecule:
Sodium chromate has the chemical formula Na[tex]\(_2\)[/tex]CrO[tex]\(_4\)[/tex]. This means that each molecule of sodium chromate contains 2 sodium (Na) atoms.

2. Understand Avogadro's Number:
One mole of any substance contains Avogadro's number of entities (atoms, molecules, etc.), which is [tex]\(6.022 \times 10^{23}\)[/tex].

3. Calculate the Total Number of Sodium Atoms:
Since each molecule of sodium chromate contains 2 sodium atoms, the total number of sodium atoms in one mole of sodium chromate can be calculated by multiplying the number of sodium atoms per molecule by Avogadro's number:
[tex]\[ \text{Number of sodium atoms in one mole} = 2 \times 6.022 \times 10^{23} = 1.2044 \times 10^{24} \][/tex]

4. Select the Appropriate Answer:
The correct answer matches one of the given options. Thus, the number of sodium atoms in one mole of sodium chromate is:
[tex]\[ \boxed{1.2 \times 10^{24} \text{ atoms}} \][/tex]

Therefore, the correct option is:
B. [tex]\( 1.2 \times 10^{24} \)[/tex] atoms.