Question

3 grams of carbon completely combines with 8 gram of oxygen to form 11gram of CO2. In a sample of 44 gram of CO2 determine the mass of carbon and oxygen​

Answer 1

Answer:-

• Mass of Carbon = 12g

• Mass of Oxygen = 32g

Explanation:-

It is given that 3 grams of Carbon completely combines with 8 gram of Oxygen to form 11g if CO₂ .

The above statement shows that the ratio by number of atoms for CO₂ is C:O = 3:8

_________________________

[ • Atomic Mass of Carbon = 12u

• Atomic Mass of Oxygen = 16u

Hence, ratio by number of atoms :-

=> C:O = 12:16×2

=> C:O = 12:32

=> C:O = 3:8 _________________________]

Now, let the required mass of Carbon and Oxygen be 3x and 8x respectively.

=> 3x + 8x = 44

=> 11x = 44

=> x = 44/11

=> x = 4

Thus:-

→ Required mass of Carbon = 3×4 = 12g

→ Required mass of Oxygen = 8×4 = 32g

Answer 2

We got,

Ratio of mass of C and O in CO2 = 3:8

Now we have, mass of CO2 = 44 g

Let, common in the ratio here be = k

So, mass of C = 3k; mass of O = 8k.

∴ 3k + 8k = 44 g

⇒ 11k = 44 g

⇒ k = 4 g

∴ Mass of C here = 3k = 12g; mass of O here = 32 g.