Question

The characteristic flame test colors of metal ions are due to atomic emission spectra. Discuss the relationship between the absoption and rmission of light and the factors responsible for flame test colors. Include quantization of electron energy levels and Planck's law in your answer.The

Answer 1

Answer:

• The characteristics flame test color of metals ions are due to atomic emission spectra.

Explanation:

• When an atom absorb a specific wavelength radiation, the electron inside in it, move from lower energy level to higher energy level. Such a process is known as absorption. When this excited electron come back to its ground state, it loses energy in specific color depending upon the frequency of absorbed radiation. Such a process is known as emission .

Energy level:

• As an atom has different energy level, the level near to nucleus has less energy as compare to level that are far from nucleus. So electrons move from lower energy level to higher level by gaining specific energy, and after excitation it come back  from high energy level to low energy level with emission of light.

Planck's Concept

• There is specific energy difference between two energy level, so such energy difference is quantized. only those radiation will be absorbed that are equal to the energy difference between two level.

Answer 2

The colors of the flame arise due to absorption or emission spectra. Temperature, electronic spectra, energy difference are some of the factors responsible for flame test colors.

Further explanation:

Flame test is an analytical technique that is used to detect the presence of specific elements on the basis of their corresponding spectrum. The flame colors are dependent on temperature.

Factors responsible for flame test colors:

1. Oxygen supply

In the case of hydrocarbon flames, it is the most important factor in determining the color of the flame. It determines the rate of combustion, temperature and reaction paths, thereby forming different colors.

2. Energy difference

Flame colors are related to the energy difference between the two energy levels of a particular atom. Different atoms have different allowed energy levels for their electrons and therefore producing different flame colors.

3. Temperature

It plays a major role in flame colors. For example, the inner core of candle flame appears blue with a temperature around 1670 K. The color inside the flame ranges from yellow, orange to red. More the distance from the center of the candle flame, lower will be the temperature and vice-versa.

4. Electronic spectra

Each element has its own characteristic electronic spectra that are responsible for producing different flame colors for different elements.

Electronic transition:

It is a process that occurs when an electron undergoes emission or absorption from one energy level to another energy level.

When an electron undergoes a transition from a lower energy level to a higher energy level then it requires energy to complete the process. This transition is an absorption process.

When an electron undergoes a transition from higher energy level to lower energy level then it emits energy to complete the process. This transition is an emission process.

The ground state of an atom is the lowest energy state whereas the excited state has energy greater than that of the ground state.

When light is made to fall on any substance, electrons are emitted from it. This is known as the photoelectric effect and the emitted electrons are called photoelectrons. The electrons are emitted because of the transference of energy from light to the electrons.

According to Planck’s law, energy is proportional to the frequency and is expressed as follows:

${\text{E}}{\mathbf{ = }}{h\nu }}$                                   …… (1)

Here,

$E$is the energy.

$h$is the Plank’s constant.

$\nu$is the frequency.

According to equation (1), only radiations with particular frequencies can be transmitted by an atom, thereby resulting in absorption or emission of light.

As long as an electron remains in the same energy level, it neither absorbs nor emits energy. But energy is absorbed when an electron goes from lower to higher energy level and it is emitted when an electron jumps from higher to lower energy levels.

Learn more:

1. Which transition is associated with the greatest energy change? https://brainly.com/question/1594022

2. Describe the spectrum of elemental hydrogen gas: https://brainly.com/question/6255073

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Atomic structure

Keywords: electronic transition, absorption, emission, lower, higher, energy level, excited state, ground state, emit, lower energy state, flame test, temperature, spectra, oxygen supply.