Electronic Configuration of Elements

Q.

What Is the Valency of Helium?

Q.

What is the electron configuration for Helium?

Q. Assertion: Elements in the same column have similar properties.
Reason: Periodic properties of elements is a function of atomic number.

1. Both assertion and reason are false.
2. Both assertion and reason are true and reason is the correct explanation of assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are true but reason is not the correct explanation of assertion.

Q. How many electrons are present in the outermost shell of a carbon atom?

1. 4

Q.

The atoms of metals have less than 4 valence electrons.

1. True
2. False

Q. How many electrons are present in the outermost shell of a carbon atom?

1. 4

Q.

An inert gas having a duplet structure is __.

Q.

An element has the valency of +3 what will be the formula of its sulphide

Q.

Define the term valency of an element. Can it be a fractional number?

Q. Match the elements with the number of electrons present in their L-shell.
$$\begin{array}{cc}\text{Elements}& \text{Electrons in L-shell}\\ \text{(a) Hydrogen}& \text{(i) 8}\\ \text{(b) Nitrogen}& \text{(ii) 0}\\ \text{(c) Lithium}& \text{(iii) 1}\\ \text{(d) Neon}& \text{(iv) 5}\end{array}$$

1. $\text{(a) - (i)}$
   $\text{(b) - (iv)}$
   $\text{(c) - (ii)}$
   $\text{(d) - (iii)}$
2. $\text{(a) - (ii)}$
   $\text{(b) - (iv)}$
   $\text{(c) - (iii)}$
   $\text{(d) - (i)}$
3. $\text{(a) - (iii)}$
   $\text{(b) - (i)}$
   $\text{(c) - (ii)}$
   $\text{(d) - (iv)}$
4. $\text{(a) - (iv)}$
   $\text{(b) - (iii)}$
   $\text{(c) - (ii)}$
   $\text{(d) - (i)}$

Q. Which of the following element have the same chemical properties as an element having electronic configuration 2, 8, 5?

1. Fluorine (9)
2. Sodium (11)
3. Nitrogen (7)
4. Argon (18)

Q.

Match the following statements

$\begin{array}{cc}\text{(a)f block elements}& \left(i\right)Group1and2\\ \text{(b)d block elements}& \left(ii\right)Group13to17\\ \text{(c)p block elements}& \left(iii\right)Group3to12\\ \text{(d)s block elements}& \left(iv\right)LanthanidesandActinides\end{array}$

1. (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii).

2. (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i).

3. (a)-(iii), (b)-(ii), (c)-(iv), (d)-(i).

4. (a)-(i), (b)-(iii), (c)-(iv), (d)-(ii).

Q. How does electronic configuration of atoms change in a period with increase in atomic number? [2 marks]

Q.

Name three non-metals which have -1 valency.

Q.

IE2 for alkali metals shows a jump whereas IE3 for alkaline earth metals shows a jump.Explain.

Q.

Define valence electrons.

Q. In the given diagrams, the circular rings around the nucleus represents:

1. 
2. 
3. 
4. 

Q. How many shells in calcium atom are filled with electrons?

1. Three
2. Four
3. Five
4. Two

Q. Which of the following element needs only one electron to attain noble gas configuration?

1. Chlorine
2. Sodium
3. Oxygen
4. Neon

Q. Match the elements with their correct electronic structure.

1. 
2. Neon
3. Carbon
4. 
5. 
6. Sodium

Q. Electronic configuration of elements P, Q, R and S are given below:
P - (2, 2)
Q - (2, 8, 2)
R - (2, 8, 5)
S - (2, 5)
Which of the following options is correct?

1. P and Q belong to second period and R and S belong to third period.
2. P and R belong to second period and Q and S belong to third period.
3. P and S belong to second period and R and Q belong to third period.
4. S and Q belong to second period and R and P belong to third period.

Q. Choose the correct pairs based on the maximum electrons that can be accomodated in that shell.

1. K - shell
2. L - shell
3. M - shell
4. N - shell
5. 8 electrons
6. 18 electrons
7. 2 electrons
8. 32 electrons

Q.

The maximum number of electrons that can be accomodated in the L shell is:

1. 2

2. 8

3. 18

4. 32

Q. Identify the elements with seven valence electrons.

1. Fluorine
2. Nitrogen
3. Phosphorus
4. Chlorine
5. Bromine
6. Calcium
7. Helium
8. Iodine
9. Astatine