Question

Problem 3.6
The first ionization enthalpy (AH) values
of the third period elements, Na, Mg and
Si are respectively 496, 737 and 786 kJ
mol!. Predict whether the first AH value
for Al will be more close to 575 or 760 kJ
mol-'? Justify your answer.​

Answer 1

Explanation:

The electronic configuration are as follows;

1

1Na(3s)

1

,

1

2Mg(3s)

2

,

1

3Al(3s)

2

(3p)

1

,

1

4Si(3s)

2

(3p)

2

The ionisation energy of Mg will be larger than that of Na due to fully filled configuration (3s)

2

The ionization of Al will be smaller than that of Mg due to one electron extra than stable configuration but smaller than Si due to increase in effective nuclear charge of Si.

Na<Mg>Al<Si

So, the first Δ

t

H value of Al will be more close to 575 Kj/mol. The value for Al should be lower than that of Mg because of effective shielding of 3p electron from the nucleus by 3s electron.

Answer 2

Answer:

ohh wooow good!!

Now you are in 11th std????