Question

an unknown compound was found to contain 34.24%sodium,18%carban,47.76%oxygen the molar mass of compound is 134gmol.find out its empirical formula and molecular formula​

Answer 1

hope it helps..........

Answer 2

Given info : an unknown compound was found to contain 34.24% sodium, 18%carban ,47.76% oxygen the molar mass of compound is 134gmol.

To find : the emperical formula and molecular formula.

Solution : find percentage/atomic mass ratio of each element.

For sodium ⇒34.24/23 ≈ 1.5

For carbon ⇒18/12 = 1.5

For oxygen ⇒47.76/16 ≈ 3

Find simple ratio of all gotten (percentage/atomic mass ratio) terms.

Na : C : O = 1.5 : 1.5 : 3 = 1 : 1 : 2

Therefore the emperical formula is NaCO₂

Weight of compound for emperical formula = 23 + 12 + 16 × 2 = 23 + 12 + 32 = 67g

Using formula , molecular weight = n × emperical weight

⇒134 = n × 67

⇒n = 2

Therefore molecular formula is 2(NaCO₂) = Na₂C₂O₄