Calculate the energy of a photon of electromagnetic radiation at each of the following wavelengths. a. 632.8 nm (wavelength of red lightfrom helium-neon laser)
b. 503 nm (wavelength of maximumsolar radiation)
c. 0.0520 nm (a wavelength contained inmedical X-rays)

A)566×10^-16J

B)711.99×10^-16J

C)688.69×10^-12J

Explanation:

A)

But we know that

1 nm = 10^-9 m

Then we can Convert from nanometer to metre which is SI unit

632.8 nm = 632.8×10^-9 m = 6.328×10^-7 m

The speed of light is c = 2.998×10^8 m/s

λ = 6.328×10^-7 m

But the frequency can be calculated as;

ƒ = c / λ

ƒ = (2.998×10^8 m/s) / (6.328×10^-7 m)

Then

ƒ = 4.738×10^14 s-1

To calculate Energy we use

Energy= hf

Where h is plank constant= 6.626× 10^-34

Energy= 6.626× 10^-34 × 4.738×10^14=566×10^-16J

B)

But we know that

1 nm = 10^-9 m

Then we can Convert from nanometer to metre which is SI unit

Then 503 nm = 503×10^-9 m = 5.03×10^-7 m

c = 2.998×10^8 m/s

λ = 5.03×10^-7 m

But the frequency can be calculated as;

ƒ = c / λ

ƒ = (2.998×10^8 m/s) / (5.03×10^-7 m)

ƒ = 5.960×10^14 s-1

Energy= 6.626× 10^-34 × 5.960×10^14 s-1= 711.99×10^-16J

C)

1 nm = 10^-9 m

0.0520 nm = 0.0520×10^-9 m = 5.20×10^-11 m

Where the speed of light is

c = 2.998×10^8 m/s

λ = 5.20×10^-11 m

But the frequency can be calculated as;

ƒ = c / λ

ƒ = (2.998×10^8 m/s) / (5.20×10^-11 m)

ƒ = 5.765×10^18 s-1

Energy= 6.626× 10^-34 × 5.765×10^18 s-1= 688.69×10^-12J

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.