Atomic Size

Q. Name the elements with highest and lowest ionization energies in the first three periods.

Q.

2× ${10}^8$ atoms of carbon are arranged side by side. Calculate the radius of carbon atom if the length of this arrangement is 2.4 cm.

Q.

If the diameter of a carbon atom is 0.15 nm, calculate the number of carbon atoms which can be placed side by side in a straight line across length of scale of length 20 cm long.

Q.

The diameter of zinc atom is 2.6 A. Calculate (a) radius of zinc atom in pm and (b) number of atoms present in a length of 1.6 cm if the zinc atoms are arranged side by side lengthwise.

Q.

Which molecule does not have net zero dipole moment?

1. $C{O}_2$

2. $H_2$

3. $C{l}_2$

4. $H_{2}O$

Q. $H_{2}O$ is dipolar, whereas $Be{F}_2$ is not. It is because

1. The electronegativity of F is greater than that of O
2. $H_{2}O$ involved hydrogen bonding whereas $Be{F}_2$ is a discrete molecule
3. $H_{2}O$ is linear and $Be{F}_2$ is angular
4. $H_{2}O$ is angular and $Be{F}_2$ is linear

Q. Number of lone pairs on Xe in $XeO{F}_4$ is/are ?

1. \N
2. 1
3. 2
4. 3

Q.

What is the geometry of $H_{2}S{O}_4$?

1. Square bipyramidal

2. Tetrahedral

3. Trigonal bipyramidal

4. Pentagonal bipyramidal

Q. Which of the following has a zero dipole moment?

1. 1, 1-Dichloroethylene
2. cis-1, 2-Dichloroethylene
3. trans-1, 2-Dichloroethylene
4. None of these

Q.

Arrange in order of increasing dipole movement.

I. Toulene

II. m - dichlorobenzene

III. o - dichlorobenzene

IV. p - dichlorobenzene

1. $I<IV<II<III$

2. $IV<I<II<III$

3. $IV<I<III<II$

4. $IV<II<I<III$

Q.

The molecule having T-shape is:

1. $S{F}_4$

2. $Cl{F}_3$

3. $BeC{l}_2$

4. $I_3^{-}$

Q. Cs atoms are the largest naturally occurring atoms. The radius of Cs atom is $2.6\mathring{A}$. The number of moles of Cs atoms to be laid side by side to give a row of Cs atoms 2.50 cm long is $x\times {10}^{-17}$. The value of x is

Q. State the trends in ionization energy :
across the period,