Question

A sample of propane(c3h8)has 3.84x10^24 H atoms.

a) how many carbon atoms does the sample contain?
b) what is the total mass of the sample?​

Answer 1

A) 14. 25 × 10²³ Carbon atoms

B) 34.72 grams

Step-by-step explanation:

1 molecule of Propane has 3 atoms of Carbon and 8 atoms of Hydrogen.

The sample has 3.84 × 10²⁴ H atoms.

If 8 atoms of Hydrogrn are present in 1 molecule of propane.

3.84 × 10²⁴ H atoms are present in

`\mathfrak{ (3.8 )/(8) * 10 ^(24)}`

= 4.75 × 10²³ molecules of Propane.

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No. of Carbon atoms in 1 molecule of propane = 3

=> C atoms in 4.75× 10²³ molecules of Propane = 3 × 4.75 × 10²³

= 14.25 × 10²³

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Gram Molecular Mass of Propane(C3H8)

= 3 × 12 + 8 × 1

= 36 + 8

= 44 g

1 mole of propane weighs 44g and has 6.02× 10²³ molecules of Propane.

=> 6.02 × 10²³ molecules of Propane weigh = 44 g

=> 4. 75 × 10²³ molecules of Propane weigh =

`\mathsf{ \frac{44 }{6.02 * {10}^(23) } * 4.75 * {10}^(23) }`

`\mathsf{ = \frac{44 }{6.02 * \cancel{{10}^(23) }} * 4.75 * \cancel{ {10}^(23)} }`

`\mathsf{ = (44 )/(6.02 ) * 4.75 }`

= 34.72 g