Advertisements
Advertisements
Question
Find the empirical formula and the molecular formula of an organic compound from the data given below :
C = 75.92%, H = 6.32% and N = 17.76%
The vapour density of the compound is 39.5.
[C = 12, H = 1, N = 14]
Advertisements
Solution
| Element | % | |
| C | 75.92 | `75.92/12 = 6.32/1.26 = 5` |
| H | 6.32 | `6.32/1 = 6.32/1.26 = 5` |
| N | 17.76 | `17.76/14 = 1.26/1.26 = 1` |
Empirical formula ; - C5H5N
Molecular weight = 2 × Vapour Density
= 2 × 39.5
= 79
Empirical formula weight = C × 5 + H × 5 + N × 1
= 12 × 5 + 1 × 5 + 14 × 1
= 60 + 5 + 14
= 79
`n = "Molecular weight"/("Empirical" "formula" "weight" )`
∴ Molecular formula = Empirical formula = C5H5N
APPEARS IN
RELATED QUESTIONS
Identify the term or substance based on the descriptions given below:
The property by virtue of which the compound has the same molecular formula but different structural formulae.
A compound made up of two elements X and Y has an empirical formula X2Y. If the atomic weight of X is 10 and that of Y is 5 and the compound ha a vapor density 25, find its molecular formula.
Give the empirical formula of C2H2
A compound contains 87.5% by mass of nitrogen and 12.5% by mass of hydrogen. Determine the empirical formula of this compound.
Determine the empirical formula of the compound whose composition by mass is 42% nitrogen, 48% oxygen and 9% hydrogen.[N=14,O=16,H=1]
The percentage composition of sodium phosphate, as determined by analysis is : 42.1% Na, 18.9% P, 39% of O. Find the empirical formula of the compound.
[H =1, N =14, Na = 23, P = 31, Cl = 35.5, Pt = 195]
Explain the term empirical formula.
0.2 g atom of silicon combine with 21.3 g of chlorine. Find the empirical formula of the compound formed.
Silicon (Si = 28) forms a compound with chlorine (Cl = 35.5) in which 5.6 g of silicon combines with 21.3 g of chlorine. Calculate the empirical formula of the compound.
A compound has the following percentage composition by mass: carbon 14.4%, hydrogen 1.2% and chlorine 84.5%. By what type of reaction could this compound be obtained from ethylene?
