Question

4. A sample of ethanol
contains 3.01 x 10^23 carbon
atoms. The sample
contains?
1. 0.25 moles oxygen
atoms
2. 1.5 moles hydrogen
atoms
3. 0.5 moles ethanol
molecules

Answer 1

Explanation:

Given -

• A sample of C2H5OH contains 3.01 × 10²³ carbon atoms.

To Find -

• moles ?

Solution -

As we know that -

Number of atom = n × 6.02 × 10²³

Then,

3.01 × 10²³/6.02 × 10²³ = n

n = 1/2

n = 0.5

Hence,

3.01 × 10²³ atoms of C2H5OH contains 0.5 mole.

Therefore,

Option 3 is correct.

Some related formulas (Moles Concept) -

1. Mass = n × GAM/GMM
2. Volume = n × 22.4 (L)
3. Volume = n × 22,400 (mL)
4. Number of atoms = n × 6.02 × 10²³

Answer 2

Explanation:

Refer to this attachment