One molecule of bromine and two molecule of potassium chloride combine in a reaction. How many atoms are in the products?

Question

1. two
2. six
3. four
4. Three

Answer 1

The balanced chemical equation for the reaction of one molecule of bromine (Br₂) and two molecules of potassium chloride (2KCl) is:

Br₂ + 2KCl → 2KBr + Cl₂

In the products, we have 2 moles of potassium bromide (2 KBr) and 1 mole of chlorine gas (Cl₂).

To find the number of atoms in the products, we need to multiply the number of moles by Avogadro's number, which is approximately 6.022 × 10²³.

For 2 moles of potassium bromide, we have:
2 moles KBr × 6.022 × 10²³ atoms/mole = 12.044 × 10²³ atoms

For 1 mole of chlorine gas, we have:
1 mole Cl₂ × 6.022 × 10²³ atoms/mole = 6.022 × 10²³ atoms

Adding these two quantities together:
12.044 × 10²³ + 6.022 × 10²³ = 18.066 × 10²³

Therefore, there are approximately 18.066 × 10²³ atoms in the products.

So the correct answer is 18.066 × 10²³ atoms, which is closest to option 4. Three.