AIEEE Questions

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All chemistry is based on sharing electrons. A chemical bond forms when two atoms transfer or share outer electrons to complete their outer shells.

In chemistry, a metal is an element that readily forms positive ions (cations) and has metallic bonds. Metals are opaque, lustrous elements that are good conductors of heat and electricity. Most metals are malleable and ductile and are, in general, denser than the other elemental substances.

Examples of metals are aluminium, copper, iron, tin, gold, lead, silver, titanium, uranium, and zinc.

Here Se - Selenium is an element but is not a metal, S - Sulphur is not a metal and I - Iodine is also not a metal.

Hence, Zn - Zinc is the only metal in the given options.

Here given the required digit number is 4 digit.

It must be divisible by 5. Hence, the unit's digit in the required 4 digit number must be 0 or 5. But here only 5 is available.

x x x 5

The remaining places can be filled by remaining digits as 5 x 4 x 3 ways.

Hence, number 4-digit numbers can be formed are 5 x 4 x 3 = 20 x 3 = 60.

A barometer is a tool that measures air pressure

A rising barometer indicates increasing air pressure, a falling barometer indicates decreasing air pressure.

In space, there is a nearly complete vacuum, so the air pressure is zero.

A nitrogenous base, or nitrogen-containing base, is an organic molecule with a nitrogen atom that has the chemical properties of a base. The main biological function of a nitrogenous base is to bond nucleic acids together. A nitrogenous base owes its basic properties to the lone pair of electrons of a nitrogen atom.

In DNA, four bases have been found. They are

1. Adenine (A),

2. Guanine (G),

3. Cytosine (C) and

4. Thymine (T).

The first three of these bases are found in RNA also but the fourth which is Uracil (U) is absent in it.

RNA contains cytosine and uracil as pyrimidine bases while DNA has cytosine and thymine.

The four bonds of carbon tetrachloride (CCl4) are polar, but the molecule is nonpolar because the bond polarity is cancelled by the symmetric tetrahedral shape. Hence, making the net dipole as zero and molecule as non-polar.

When other atoms substitute for some of the Cl atoms, the symmetry is broken and the molecule becomes polar.

Indica is the book written by Greek historian "Megasthenes" in which he described India like how is the Indians life, what way of life is followed, etc...