Calculate the wavelength, in nanometers, of the light emitted by a hydrogen atom when its electron falls from the n = 7 to the n = 4 principal energy level. recall that the energy levels of the h atom are given by en = –2.18 × 10–18 j(1/n2)

The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.

Explanation:

The energy of nth energy levels of the H atom is given as:

Energy of the seventh energy level =

Energy of the seventh energy level =

Energy of the light emitted will be equal to the energy difference of the both levels.

Wavelength corresponding to energy E can be calculated by using Planck's equation:

The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.

both adhesion and cohesion are attractions.

they are different in that adhesion is the force of attraction between the molecules of two different substances, whereas cohesion is the force of attraction between molecules of the same substance.

possible examples include capillary action, in which the adhesion between water and glass causes the water to rise in a narrow tube against the force of gravity.

because of hydrogen bonding, water is extremely cohesive.

this causes molecules on the surface of water to be drawn inward, which is why drops of water form beads on smooth surfaces.

hope this .