Chapter 15, Problem 15.2QAP

Interpretation Introduction

(a)

Interpretation:

The meaning of fluorescence is to be stated.

Concept introduction:

When a substance absorbs radiation or light, it may emit or reflect it back.

Interpretation Introduction

(b)

Interpretation:

The meaning of phosphorescence is to be stated.

Concept introduction:

When a substance absorbs radiation or light, it may or may not emit it back.

Interpretation Introduction

(c)

Interpretation:

The meaning of resonance fluorescence is to be stated.

Concept introduction:

The atom can interact with fields of same frequency as them.

Interpretation Introduction

(d)

Interpretation:

The meaning of singlet state is to be stated.

Concept introduction:

There are magnetic spins on electrons in an atom. The magnetic spin can either be positive or negative.

Interpretation Introduction

(e)

Interpretation:

The meaning of triplet state is to be stated.

Concept introduction:

There are negative and positive magnetic spins on each electron in an atom.

Interpretation Introduction

(f)

Interpretation:

The meaning of vibrational relaxation is to be stated.

Concept introduction:

When a substance absorbs radiation or light, the molecules get excited. Then the energy is reflected back after some time.

Interpretation Introduction

(g)

Interpretation:

The meaning of internal conversion is to be stated.

Concept introduction:

The molecules get to the excited state by absorbing energy and come back to ground state by emitting this energy.

Interpretation Introduction

(h)

Interpretation:

The meaning of external conversion is to be stated.

Concept introduction:

The molecules get to the excited state by absorbing radiation and come back to ground state by emitting this radiation.

Interpretation Introduction

(i)

Interpretation:

The meaning of intersystem crossing is to be stated.

Concept introduction:

There is a possibility of changing states from singlet state to triplet state. It is only possible when spin orbit coupling is present.

Interpretation Introduction

(j)

Interpretation:

The meaning of predissociation is to be stated.

Concept introduction:

The bond of any molecule can be broken due to its unstable excited state.

Interpretation Introduction

(k)

Interpretation:

The meaning of dissociation is to be stated.

Concept introduction:

The bond of any molecule can be broken due to excessive absorption of energy.

Interpretation Introduction

(l)

Interpretation:

The meaning of quantum yield is to be stated.

Concept introduction:

The numbers of photons absorbed and emitted are different. These numbers are needed to find the yield of a substance.

Interpretation Introduction

(m)

Interpretation:

The meaning of chemiluminescence is to be stated.

Concept introduction:

The light that is absorbed by the molecules of a substance can be emitted because of different ways.