Photochemical Reaction

Q.

When ferrous sulphate is heated the following reaction takes place:

$2FeS{O}_4\left(s\right)\to F{e}_2{O}_3\left(s\right)+S{O}_2\left(g\right)+S{O}_3\left(g\right)$

The above reaction is called __________ of ferrous sulphate.

1. Thermal Decomposition

2. Double displacement

3. Thermal Displacement

4. Combination

Q. $2AgCl\stackrel{light}{\to }2Ag+C{l}_2$
This is an example of reaction and light is being during this reaction.

1. combination
2. photo-decomposition
3. thermal decomposition
4. absorbed
5. liberated

Q.

What are photochemical reactions? Explain with the help of examples.

Q.

CaO and $C{O}_2$ are produced by heating $CaC{O}_3$. What are the type of the reaction and the process?

1. Decomposition reaction and endothermic process

2. Decomposition reaction and exothermic process

3. Combination reaction and endothermic process

4. Displacement reaction and endothermic process

Q.

Reactions which take place in the presence of light are known as ____________.

Q.

Define:

(a) Photochemical reaction

(b) Electrochemical reaction.

Give one example in each case.

Q.

Name the solution used for removing grease stains from woolen clothes.

Q.

State the colour of the water that has entered round-bottomed flask.

1. Red

2. White

3. Colourless

4. Blue

Q.

State the energy changes taking place when the photographic film is exposed to the sunlight.

Q.

Explain photochemical reaction?

Q.

Soluble salt like sodium sulphite can be prepared in the laboratory by the process of

1. titration

2. synthesis

3. displacement

4. decomposition

Q. Hydrogen and chlorine combine together to form hydrochloric acid when exposed to sunlight. This type of reactions are called :

1. photochemical reactions
2. physical changes
3. periodic changes
4. electrochemical reactions

Q.

$N{a}_{2}C{O}_3$ does not decompose on heating where as $CaC{O}_3$ decomposes. Why?

1. Higher cation charge

2. Presence of Oxygen

3. Lower anion charge

4. Insufficient data

Q.

Define photochemical reactions.

Q.

The following reaction is a/an –
$C+O_2\to C{O}_2+Heat$

1. Combination reaction

2. Oxidation reaction

3. Exothermic reaction

4. All of the above

Q. Silver chloride undergoes decomposition in presence of sunlight.

1. True
2. False

Q.

Define:

(a) Photochemical reaction

(b) Electrochemical reaction.

Give one example in each case.

Q.

Which of the following is Photo-Chemical Reaction?

1. Photosynthesis

2. Decomposition of Silver Nitrate

3. Dissociation of Acidulated Water

4. Dissociation Of Potassium Chloride

Q.

Which of the following is not a decomposition reaction?

1. H₂CO₃ → H₂O + CO₂

2. H₂ + Cl₂ → 2HCl

3. 2KClO → 2KCl + 3O₂

4. CaCO₃ → CaO + CO₂

Q. The law of photochemical equivalence was given by_______

1. Drapper
2. Einstein
3. Grauths
4. Labbert

Q. Chemical reactions initiated by light are called:

1. electrochemical reactions
2. isothermal reactiorts
3. spectroscopic reactions
4. photochemical reactions

Q. Define a Photochemical reaction. Give one example.

Q.

If a child is eating bread, our body decomposes it into carbon dioxide and water. Which type of reaction is this?

1. Displacement Reaction

2. Decomposition Reaction

3. Combination Reaction

4. Precipitation Reaction

Q.

Complete the following reaction:

${\mathrm{H}}_2\mathrm{O}\stackrel{\mathrm{electricity}}{\to }$

Q.

Define:

(a) Photochemical reaction

(b) Electrochemical reaction.

Give one example in each case.

Q. Photochemical reactions have the following characteristics:

1. These requires photons to interact with chemical species
2. Light is essential for photochemical reaction
3. Each molecule absorbs only one photon to get itself excited
4. It is not necessary for an excited molecule to show always chemical change

Q. The pigment that absorbs sunlight is
(a) haemoglobin.
(b) chlorophyll.
(c) chloroplast.
(d) starch.

Q. The study of photo-chemical reactions is called:

1. photonics
2. photochemistry
3. photography
4. none of the above

Q. $O_2$ undergoes photochemical dissociation into one normal oxygen atom and one oxygen atom, $1.2eV$ more energetic than normal. The dissociation of $O_2$ into two normal atoms of oxygen requires $482.5kJ/mol$. The maximum wavelength effective for photochemical dissociation of $O_2$ is $(1eV=96.5kJ/mol)$

1. $248nm$
2. $1033.3nm$
3. $1236.2nm$
4. $200nm$

Q. Match the types of reactions with their general representation.

1. $A+B\to \mathrm{AB}$
2. $\mathrm{AB}+C\to \mathrm{AC}+B$
3. Decomposition
4. Displacement
5. $AB\to A+B$
6. Combination