Question

Q.25 Write general electronic configuration of d and f block elements.
Q.26 What will be the wavelength of a ball of mass 0.1kg moving with velocity of 10 m/s?
Q.27 A solution is prepared by adding 2 g of a substance A to 18 g of water. calculate the mass percent
of substance A.​

Answer 1

Answer:

25. The general outer electronic configuration of d block elements is

(n−1)d(1−10)ns(0−2).

The general outer electronic configuration of f block elements is

(n−2)f(0−14)(n−1)d(0−1)ns2.

26. λ=(6.626*10^-34)/{(0.1)*(10)}

λ=6.626*10^-34 meter

Orλ= 6.626*10^-24 angstorm.

27. Mass percent of solute =

mass of solution

mass of solute

×100

Mass of solute = 2 g

Mass of solvent = 18 g

Mass of solution = 20 g

∴ Mass percent of solute =

20

2

×100

=10%

Answer 2

Answer - Q.25 The general electric configuration of D block element is (n−1)d(1−10)ns(0−2)

And general electronic configuration of F block element is (n−2)f(0−14)(n−1)d(0−1)ns2.