Atomic Radius

Q.

Why metallic character decreases across a period and increases down a group?

Q.

The atomic radius decreases as we move across a period because:

1. atomic mass increases.

2. atomic number increases.

3. more electrons are added.

4. effective nuclear charge increases.

Q.

Define atomic size. How does it vary in a period and in a group ?

Q.

Why do the elements in the same group have similar chemical properties?

Q.

Mischmetal is an alloy consisting mainly of

1. lanthanoid and actinoid metals

2. lanthanoid metals

3. actinoid metals

4. actinoid and transition metals

Q.

State the characteristics of groups in the periodic table.

Q.

Is aluminium a good conductor of electricity?

Q.

What is the radius of hydrogen atom?

Q.

Which orbitals have the highest shielding effect?

Q.

Most non-metallic among F, Cl, Br, I, and At is:

1. F

2. I

3. Cl

4. At

Q.

What is the element in Group 4 Period 4?

Q.

The size of iso electronic species $F^{‑}$ , $Ne$ and $N{a}^{+}$ is affected by

1. Electron-electron interaction in the outer orbitals

2. None of the factors because their sizes the same.

3. Nuclear charge (Z)

4. Valence principal quantum number (n)

Q. Calculate effective nuclear charge of sodium with ex plantation. Also provide me the rules fully explainEd, .

Q.

Which of the following is liquid at room temperature?

1. Oxygen

2. Bromine

3. Fluorine

4. Sulphur

Q. Arrange the following elements in the increasing order of their atomic radii.
Hydrogen, potassium, sodium, lithium

1. Hydrogen < lithium < sodium < potassium
2. Potassium < hydrogen < lithium < sodium
3. Hydrogen < potassium < sodium < lithium
4. Potassium < sodium < lithium < hydrogen

Q. Give reason
The size if fluorine ion is greater than fluorine atom

Q.

An atom of phosphorus has the symbol
$3115P$. Give the number of protons, neutrons and electrons in an atom of phosphorus.

Number of protons __(A)___.
Number of neutrons __(B)___ .
Number of electrons __(C)___ .

1. (A) - 15, (B) - 16, (C) - 15
2. (A) - 15, (B) - 15, (C) - 15
3. (A) - 15, (B) - 15, (C) - 16
4. (A) - 16, (B) - 16, (C) - 15

Q.

The alkali metal with the smallest atomic radius is __________.

Q.

Define atomic size. Give its unit of measurement. In the modem periodic table what trend is observed in the atomic radius in a group and a period and why is it so?

Q.

What is the name of ion with the formula ${\mathrm{CO}}_3^{2-}$?

Q. Which of the following indicates period number?

1. The number of electrons.
2. The number of shells.
3. Valency
4. Atomic mass

Q.

What is the smilarisimil and differences between Atom , Ion and molecules with their respective defination?

Q. Arrange the following elements in the decreasing order of their atomic radius: oxygen, carbon, lithium.

1. Lithium > oxygen > carbon
2. Oxygen > carbon > lithium
3. Carbon > oxygen > lithium
4. Lithium > carbon > oxygen

Q.

The atomic number of an element 'X' is 15 . Identify its position in the modern periodic table

Q.

Why are ionic compounds insoluble in kerosene and petrol?

Q. 29. Amongst the following elements (whose electronic configurations are given below), the one having the highest ionization energy is a. [Ne]3s2 3p1 b. [Ne]3s2 3p3 c. [Ne]3s2 3p2 d. [Ar] 3d10 4s2 4p3

Q.

Which of the following molecule does not have any lone pair of electrons on the central atom?

1. H₂O

2. NH₃

3. CH₄

4. PCl₅

Q.

The atomic size of lithium is _____ than that of sodium.

Q.

Which factor is most responsible for the increase in boiling points of noble gases from $\mathrm{He}$ to $\mathrm{Xe}$?

1. Monoatomic nature

2. Increase in polarisability

3. Decrease in polarisability

4. Decrease in Ionisation energy

Q. Arrange the following elements in order of decreasing atomic size.

1. Nitrogen (N)
2. Carbon (C)
3. Phosphorus (P)
4. Sulphur (S)