Question

Calculate the energy of photon having frequency of 9.0 x 10^9 Hz

Calculate how many grams are present in 1.50 moles of H2O2

HELP

Answer 1

Solution-

Calculate the energy of photon having frequency of 9.0 x 10^9 Hz

Given

Frequency (v ) = 9.0 x 10^9 Hz = 2.69 x 10^18 m

1 hertz = 2.99 x 10^8 wavelength in meters

planck's constant (h) = 6.62 x 10^-34 J s

Velocity of light (c) = 3.00 x 10⁸ m/s

Energy ( E ) =?

Let’s calculate wavelength (λ) We know the equation

λν = c

λ = c/v = 3.00 x 10⁸ m/s/2.69 x 10^18 m

λ = 1.1 x 10^-10 s^-1

We know the equation for energy (E)

E = hc / λ = (6.62 x 10^-34 J s *3.00 x 10⁸ m s^-1)/ 1.1 x 10^-10 s^-1

E = 1.80 x 10^-15 J

Answer - Energy of photon (E) = 1.80 x 10^-15 J

Calculate how many grams are present in 1.50 moles of H2O2

Given

Moles of H2O2 = 1.50 mole

Molar mass of H2O2 = 34.0147 g/mol

Mass = ?

We know the equation

No. of moles = Mass in gram/Molar mass

Mass = No. of moles*Molar mass = 1.50 mole*34.0147 gmol^-1

Mass of H2O2 = 51.01 g

Answer - 51.01 grams are present in 1.50 moles of H2O2