Questions

Q:

What is the oxidation number of carbon in NaHCO3?

A) -4 B) -3
C) +4 D) +2
 
Answer & Explanation Answer: C) +4

Explanation:

The given compound is NaHCO3 Sodium bicarbonate which is commonly known as Baking soda.

Oxidation numbers are the charges on ions. When a neutral atom loses electrons it becomes positively charged. When a neutral atom gains electrons it becomes negatively charged.

 

Here the C represents the oxidation state of carbon in this compound. Compounds are electrically neutral, which is why we set the sum of the oxidation states equal to zero.

Sodium has a +1 oxidation state. Hydrogen has a +1 oxidation state. Oxygen has a -2 oxidation state. There are three oxygen atoms, which means the total oxidation state provided by both oxygen ions is -6. Adding up these oxidation states we get:

1 + 1 + (-6) + C = 0

-4 + C = 0

=> C = 4


This means the oxidation state of carbon in this compound is +4.

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Filed Under: Chemistry
Exam Prep: AIEEE , Bank Exams , GATE
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Q:

I have keys but no locks, I have space but no room. You can enter but can't go outside. What am I?

keys1531119373.jpg image

Answer

I am Keyboard.


A Keyboard has keys of letters, space button and enter button.

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Subject: Logic Puzzles Exam Prep: AIEEE , Bank Exams , CAT , GATE , GRE
Job Role: Analyst , Bank Clerk , Bank PO , IT Trainer

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Q:

Which of the following Asian language are UN official language

A) Chinese & Japanese B) Chinese & Hindi
C) Japanese & Arabic D) Chinese & Arrabic
 
Answer & Explanation Answer: D) Chinese & Arrabic

Explanation:
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Filed Under: World Organisations

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Q:

Neutron was discovered by

A) J.J.Thomson B) Chadwick
C) Rrutherford D) Priestley
 
Answer & Explanation Answer: B) Chadwick

Explanation:
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Filed Under: Chemistry

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Q:

Which of the following is not a good polling technique?

 

A) using a large sample B) asking clear questions
C) using a random sample D) using a push poll
 
Answer & Explanation Answer: D) using a push poll

Explanation:
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Filed Under: Indian Politics
Exam Prep: Bank Exams

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Q:

Match the characteristics with their market structure:

(a) Differentiated products, but close substitutes for consumers so their demand curves are elastic.
(b) Firm will tend to set output so that it earns maximum profits.

A) (a) Pure competition, (b) Pure Monopoly B) (a) Monopolistic competition, (b) Oligopoly
C) (a) Oligopoly, (b) Pure Monopoly D) (a) Monopolistic competition, (b) Pure Monopoly
 
Answer & Explanation Answer: D) (a) Monopolistic competition, (b) Pure Monopoly

Explanation:
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Filed Under: Indian Economy
Exam Prep: Bank Exams

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Q:

Select the correct statement (s).

A) When energy is transferred to the system from the surrounding as work, the surrounding do work on the system and the value of work (W) positive. B) When energy is transferred from the system to the surrounding as work, work is done on the surrounding and the value of W is negative.
C) Both (A) and (B) D) None of the above
 
Answer & Explanation Answer: C) Both (A) and (B)

Explanation:
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Filed Under: Chemistry
Exam Prep: AIEEE

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Q:

Deficiency of 'Thiamine'

A) Beri-Beri B) Pellagra
C) Anaemia D) Rickets
 
Answer & Explanation Answer: A) Beri-Beri

Explanation:
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Filed Under: Biology

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