Question

You have 3 moles of a substance. Which of the following statements is true?

Answer 1

Answer:

Option A is correct: You have three times the number of particles that are in 12 grams of carbon-12

Explanation:

Data given:

3 moles of substance equal to how many particles of 12 g of carbon-12.

Solution:

First we find the number of particles in 3 moles of substance

Formula used

          no. of moles = no. of particles / Avogadro's number

Rearrange the above formula

         no. of particles = no. of moles x Avogadro's number . . . . . . . . (1)

Where

Avogadro's number = 6.022 x 10²³

Put values in above equation

      no. of particles = 3 x 6.022 x 10²³ (particles/mol)

      no. of particles = 1.8066 x 10²⁴ Particles

So,

3 mole of substance have 1.8066 x 10²⁴ Particles

Now

we have to find number of particles in 12 g of carbon-12

for this first find no. of moles

formula used

       no. of moles = mass in grams/ molar mass . . . . . (2)

molar mass of carbon = 12 g/mol

Put values in equation 2

       no. of moles = 12 g / 12 (g/mol)

       no. of moles = 1 mole

So,

12 g of carbon 12 equal to 1 mole.

According to Avogadro's law 1 mole of any substance consists of 6.022 x 10²³ number of particles.

So

1 mole carbon = 6.022 x 10²³ particles

and 3 mole of substance = 1.8066 x 10²⁴ Particles

It means that we have three times number of particles that are in 12 g of carbon-2

So, Option A is correct.

A. You have three times the number of particles that are in 12 grams of carbon-12.