MCQ

Percentage Composition

By Sakshi Goel | 19 May'20 | 1 K Views

MCQ

Problem:
Percentage of Se in peroxidase enzyme is 0.5% by weight (Se = 78.4). Then the minimum molecular weight of peroxidase enzyme is
(a) 3.13 x 10⁴
(b) 15.68
(c) 1.568 x 10³
(d) 1.568 x 10⁴

Solution:

Percentage of Se = 0.5% by weight
Atomic mass of Se = 78.4
If molecular weight of enzyme = x g/mol
Even if only one atom of Se is present in enzyme, then,
0.5% of x = 78.4
$\frac{0.5}{100} Ã— x = 78.4$
$x = 78.4 Ã— \frac{100}{0.5}$ = 15680 = 1.568 x 10⁴
Correct option is (d).

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