Question

what will the energy in cal mol-1 corresponding to wavelength 800 amstrong​

Answer 1

Explanation:

ANSWER

E∝

wavelength

1

Energy is inversely proportional to wavelength.

E

1

=E

E

2

=0.25E

λ

1

=600 nm

The relation is:

E

2

E

1

=

λ

1

λ

2

λ

2

=

E

2

E

1

×λ

1

λ

2

=2400 nm

Hence, option B is correct.

Answer 2

To find:

Energy of wavelength 800 A° in calories.

Calculation:

Let energy be denoted as E ;

$\therefore \: E = \dfrac{hc}{ \lambda}$

$= > \: E = \dfrac{6.63 \times {10}^{ - 34} \times 3 \times {10}^{8} }{ 800 \times {10}^{ - 10} }$

$= > \: E = \dfrac{6.63 \times {10}^{ - 34} \times 3 \times {10}^{8} }{ 8 \times {10}^{ - 8} }$

$= > \: E = \dfrac{6.63 \times {10}^{ - 34} \times 3 \times {10}^{16} }{ 8 }$

$= > \: E = \dfrac{6.63 \times {10}^{ - 18} \times 3 }{ 8 }$

$= > E = 2.48 \times {10}^{ - 18} \: joule$

Now , we know that 1 joule = 4.2 calories.

$= > E = 2.48 \times {10}^{ - 18} \: \times 4.2 \: cal$

$= > E = 10.41 \times {10}^{ - 18} \: \: cal$

So, final answer is:

$\boxed{ \bf{ E = 10.41 \times {10}^{ - 18} \: \: cal}}$