Question: In \[C{{H}_{3}}C{{H}_{2}}Br,\]% of Br is A 80 B 75 C 70 D 7...

Question

In $C{{H}_{3}}C{{H}_{2}}Br,$ % of Br is
A 80
B 75
C 70
D 7

Answer 1

Solution

Bromoethane, often known as ethyl bromide, is a haloalkanes group chemical compound. Chemists use the abbreviation EtBr to refer to it. The odour of this volatile chemical is similar to that of ether. Bromoethane is a cheap gas that is seldom made in a laboratory. Ethanol is combined with a combination of hydrobromic and sulfuric acids in a laboratory synthesis. An alternative method includes refluxing ethanol with phosphorus and bromine, resulting in the formation of phosphorus tribromide in situ.

Complete answer:
Chemical compounds' atomic composition can be expressed in several ways, including molecular formula and percent composition.
The molecular formula is used to compute the percent composition of a compound: divide the mass of each element contained in one mole of the compound by the total molar mass of the compound.
The % composition of a compound may be determined experimentally, and these numbers can be used to derive a compound's empirical formula.
The ratio of each element's amount to the total amount of individual components contained in the compound multiplied by 100 is the percentage composition of a compound. The amount is expressed in grammes of the various components present.
Any compound's percent composition reflects its makeup in terms of all of the components present. As a result, it aids in the chemical examination of a particular substance.
The Percentage Composition Formula
The following formula is used to calculate the percentage composition of a particular element:
Mass of $C{{H}_{3}}C{{H}_{2}}Br,$ is
2 C = 2 X 12 = 24
5 H = 5 X 1 = 5
1 Br = 1 X 79 = 79
Mass of $C{{H}_{3}}C{{H}_{2}}Br,$ = 109 amu
$\%$ of $\mathrm{Br}=\dfrac{\mathrm{M} \text {ass of } \mathrm{Br}}{\text { Mass of organic compound }} \times 100$
$=\dfrac{80}{109} \times 100=73.39 \%$ or approx. $75 \%$

Hence option b is correct.

Note:
We need to know how much of a specific element is present in a combination for a variety of scientific and practical reasons. This is required by chemists in order to determine the empirical formula of numerous substances.

This formula may be used to calculate the lowest whole number of moles and the relative number of atoms in a compound. Chemists can also compute the real molecular formula using the empirical formula. The number of atoms in the chemical is shown in this formula.