Q:

The oxidation number of Cr in $K_{2} {Cr}_{2} O_{7}$ is

A) +6	B) -5
C) +3	D) -4

Answer & Explanation Answer: A) +6

Explanation:

We will rewrite the formula as an equation.

2K + 2Cr + 7O = 0

The zero comes from there being no overall charge on the compound.

Each oxidation number is represented by the element's symbol.

Since this compound is not a peroxide or superoxide, the oxidation value for O is -2

K being in group 1 has a +1 charge and therefore has an oxidation number of K is +1

Now, by putting known values in we have:

2(+1) + 2(Cr) + 7(-2) = 0

2 + 2Cr -14 = 0

2Cr = +12

Cr = +6.

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Filed Under: Chemistry
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13 6913

Q:

Sound becomes hazardous noise pollution at decibels?

A) above 120 db	B) above 80 db
C) above 50 db	D) above 30 db

Answer & Explanation Answer: A) above 120 db

Explanation:

Sound intensity is measured in decibels(db). Sound pollution above 120 db becomes more hazardous and have adverse affects on human life.

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Filed Under: Physics
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11 6912

Q:

What is one benefit of lifelong physical activity?

A) high blood pressure	B) increase in healthy eating habits
C) high physiological age	D) prevention of weight gain

Answer & Explanation Answer: C) high physiological age

Explanation:

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Filed Under: General Science
Exam Prep: AIEEE , Bank Exams
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12 6909

Q:

Who Invented Worldwide Standard Time Zones ?

A) Charles Richard Drew	B) Henry W. Seely
C) Jesse Wilford Reno	D) Sir Sandford Fleming

Answer & Explanation Answer: D) Sir Sandford Fleming

Explanation:

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Filed Under: Inventions

4 6905

Q:

Gum Kelucharan Mohapatra is a maestro of which of the following dance forms

A) Kathak	B) Kuchipudi
C) Odissi	D) Kathakali

Answer & Explanation Answer: A) Kathak

Explanation:

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Filed Under: Famous Personalities

7 6902

Q:

5 L from A are V?

Answer

5 L from A are V --- 5 Letters from Alphabets are Vowels.

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

13 6901

Q:

Which one of the following is a development expenditure

A) Irrigation expenditure	B) Civil administration
C) Debt services	D) Grant in Aid

Answer & Explanation Answer: A) Irrigation expenditure

Explanation:

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Filed Under: Indian Economy

5 6900

Q:

Who was in command of the nationalist movement before Gandhi had assumed leadership of the Congress?

A) C.R.Das	B) Motilal Nehru
C) Lala Lajpat Rai	D) Lokmanya Tilak

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