Advertisements
Advertisements
Question
A compound of lead has following percentage composition, Pb = 90.66%, O = 9.34%. Calculate empirical formula of a compound. [Pb = 207, O = 16]
Advertisements
Solution
Empirical formula of a compound:
| Element | Atomic mass |
Percentage | Relative number of | Simplest mole ratio | Whole number ratio |
| Pb | 207 | 90.66 | 90.66/207 = 0.44 | 0.44/0.44 = 1 | 1 x 3 = 3 |
| O | 16 | 9.34 | 9.34/16 = 0.58 | 0.58/0.44 = 1.32 | 1.32 x 3 = 3.96 = 4 |
Since the mole ratio for oxygen is fractional so we multiply the whole ratio by 3 to make i t a whole number.
So, the empirical formula of the compound is Pb3O4.
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 gaseous hydrocarbon contains 82.76% of carbon. Given that its vapor density is 29, find its molecular formula. [C = 12, H = 11]
Consider the following reaction and based on the reaction answer the questions that follow:
Calculate:
1) the quantity in moles of (NH4)2Cr2O7 if 63gm of(NH4)2Cr2O7 is heated.
2) the quantity in moles of nitrogen formed.
3) the volume in liters or dm3 of N2 evolved at S.T.P.
4) the mass in grams of Cr2O3 formed at the same time
(Atomic masses: H=1, Cr= 52, N=14]
Give the appropriate term defined by the statements given below :
The formula that represents the simplest ratio of the various elements present in one molecule of the compound.
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]
Explain the terms empirical formula and molecular formula.
Give example of compound whose:
Empirical formula is the same as the molecular 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.
Pratik heated 11.2 grams of element ‘M’ (atomic weight 56) with 4.8 grams of element 'N' (atomic weight 16) to form a compound. Find the empirical formula of the compound obtained by Pratik.
