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Practice MCQ Questions and answers on Chemistry-GK

Learn and practice General Knowledge questions and answers on Chemistry with very easy and understandable explanations. GK questions are very helpful different type of competitive exams. Page-10 section-10

Each section contains 100 MCQs on Chemistry .
91
The metal ion present in Vitamin B12 is
Discuss
Answer & Solution
Answer: Option B
Solution:
The structure of B12 is based on a corrin ring, which is similar to the porphyrin ring found in heme, chlorophyll, and cytochrome. It contains the biochemically rare element cobalt sitting in the center of the ring. Also called cobalamin, it is a water-soluble vitamin.
92
The metal present in vitamin B12 is
Discuss
Answer & Solution
Answer: Option B
Solution:
Vitamin B12 is also referred to as cobalamin, because it contains a metal ion (cobalt).
93
Which of the following is not present in RNA
Discuss
Answer & Solution
Answer: Option A
Solution:
Thymine base is not present in RNA. In RNA, uracil is found in place of thymine.
94
The enzyme that converts glucose to ethyl alcohol is :
Discuss
Answer & Solution
Answer: Option C
Solution:
The fermentation of sugar into ethanol is one of the earliest biotechnologies employed by humanity. Fermentation of fermentable sugars by suitable yeast produces ethanol (ethyl alcohol). Yeast is a single celled fungus containing a number of enzymes useful during fermentation. Brewers yeast and wine yeast, for example, contain zymase, an enzyme that can convert glucose to ethanol.
95
The fat of a common mussel-secretes a sticky glue that can be used to make heart implants. The unique chemical compound present in the glue is:
Discuss
Answer & Solution
Answer: Option D
Solution:
The foot of the common mussel (Mytilus edulis) produces a sticky glue due to a unique compound called mussel adhesive protein, which contains a high concentration of an amino acid, DOPA (dihydroxyphenylalanine), which can cling to wet surfaces with extraordinary strength. Besides heart implants, the compound could be used as a tooth coating to prevent dental plaque, which is caused by bacterial infection.
96
During fermentation of sugar, the compound which is always formed is :
Discuss
Answer & Solution
Answer: Option B
Solution:
Fermentation is the conversion of sugar into carbon dioxide gas (CO2) and ethyl alcohol. This process is carried out by yeast cells using a range of enzymes.
97
If a buffer solution is diluted its pH
Discuss
Answer & Solution
Answer: Option B
Solution:
Generally, dilution has no effect on the pH.
98
'Vinegar' is a commercial name of
Discuss
Answer & Solution
Answer: Option C
Solution:
Vinegar is a liquid substance consisting mainly of acetic acid (CH3CO2H) and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. It is today mainly used in the kitchen as a general cooking ingredient.
99
The apparatus used to test acidity of aqueous solution is
Discuss
Answer & Solution
Answer: Option A
Solution:
A pH meter is an electronic device used for measuring the pH (acidity or alkalinity) of a liquid. A typical pH meter consists of a special measuring probe (a glass electrode) connected to an electronic meter that measures and displays the pH reading.
100
Which one of the following organic compound is used to remove stains of iron compounds?
Discuss
Answer & Solution
Answer: Option A
Solution:
Oxalic acid is widely used as an acid rinse in laundries, where it is effective in removing rust and ink stains because it converts most insoluble iron compounds into a soluble complex ion.