The combining capacity of an element is called valency. The valence electrons determine the combining capacity of an atom. The number of bonds that an atom can form as part of a compound is expressed by the valency of the element. For example- The valency of hydrogen is 1, oxygen is 2, carbon is 4, etc.

EASY

Earn 100

Give reasons.

Isotopes of an element have the same atomic numbers.

Important Questions on Structure of The Atom

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Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

{}_{88}R^{226}

nucleus, there are

MEDIUM

Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

Isotopes of an element contains

HARD

Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

The half-life of a radioisotope is

4

hours. If the initial mass of the isotope was

200 g

, the mass remaining after

24

hours undecayed

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Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

Two atoms are said to be isobars if

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Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

Hydrogen contains three types of atoms (

{}_{1}^{1}H

protium,

{}_{1}^{2}H

deuterium,

{}_{1}^{3}H

tritium). These atoms are

EASY

Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

An isotope of which element is used in the treatment of cancer?

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Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

Which one of the following is cation

HARD

Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

Nitrogen (atomic number $7$ ) and phosphorus (atomic number $15$ ) belong to group $15$ of the Periodic Table. Write the electronic configuration of these two elements. Which one of these will be more electronegative? Why?

MEDIUM

Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

The following is the correct decreasing order of the ionic radii-

EASY

Science>Chemistry>Structure of The Atom>Atomic Number and Mass Number

The number of protons in one atom of an element