Preparation of Dioxygen

Q.

Lattice enthalpy and enthalpy of solution of NaCl are $788\mathrm{kJ}{{\mathrm{mol}}^{–1}}^{}$, and $4\mathrm{kJ}{{\mathrm{mol}}^{–1}}^{}$, respectively. The hydration enthalpy of NaCl is

1. –780 kJ mol^–1

2. 784 kJ mol^–1

3. –784 kJ mol^–1

4. 780 kJ mol^–1

Q.

Extra very pure ${\mathrm{N}}_2$ can be obtained by heating _____

Q.

Why cant we see air?

Q.

How is oxygen prepared in laboratory?

Q.

Is hydrogen harmful to humans?

Q.

When fused Calcium hydride is electrolyzed, hydrogen in liberated at anode. Why?

Q.

Why is hydrogen peroxide preferred in the preparation of oxygen gas?

Q. The number of terminal oxygen atoms present in the product B obtained from the following reaction is
$FeC{r}_2{O}_4+N{a}_{2}C{O}_3+O_2\to A+F{e}_2{O}_3+C{O}_2$
$A+H^{+}\to B+H_{2}O+N{a}^{+}$

Q.

The catalyst used in the laboratory preparation of oxygen gas from hydrogen peroxide gas is magnesium oxide.

1. True
2. False

Q.

The metal which does not form ammonium nitrate by reaction with dilute nitric acid is

1. Al

2. Fe

3. Pb

4. Mg

Q. Which of the following reactions does not produce oxygen ?

1. $O_3+KI+H_{2}O\to$
2. None
3. $H_2{O}_2+C{l}_2\to$
4. $K{O}_2\left(s\right)+C{O}_2\left(g\right)\to$

Q.

Look at the diagram and answer the following questions.

(A) What gas is prepared using this setup?

(B) Name the catalyst used in the reaction.

(C) Write the chemical reaction taking place.

Q. Finely divided metals and metal oxides on reaction with hydrogen peroxide liberate __ gas.

Q.

Give the mixture used as rocket fuel.

Q. Among the following, diamagnetic molecule is:

1. Super oxide ion
2. Oxygen molecule
3. Carbon molecule
4. Unipositive ion of nitrogen molecule

Q. Which of the following is used in artificial respiration?

1. $O_2+C{O}_2$
2. $O_2+CO$
3. $O_2+H_2$
4. all of these

Q.

State the inference drawn from the following observations:
A gas Q turns moist lead acetate paper silvery black. Identify the gas Q.

Q. Which one of the following pairs of reactants does not form oxygen when they react with each other ?

1. $F_2,$ NaOH solution (hot, concentrated)
2. $F_2,H_{2}O$
3. $C{l}_2,NaOH$ solution (cold, dilute)
4. $CaOC{l}_2,H_{2}S{O}_4$ (dilute, small amount)

Q.

When Ammonium chloride is heated a ____________ smell is produced.

Q.

State two most important uses of following non-metal:

Oxygen

Q. The micro-organisms, which can live without oxygen are:

1. bacteria
2. amoeba
3. paramoecium
4. blue-green algae

Q.

Which of the following cannot be used for the preparation of $H_2$

1. 

2. 

3. 

4. 

Q. Choose the correct statement(s) for cathode electrode in electrochemical cell?

1. Reduction occurs at cathode
2. Cathode has positive polarity
3. Cathode acts as a sink of electrons
4. All of the above

Q. Oxygen can be prepared from hydrogen peroxide and manganese dioxide in the laboratory.

1. True
2. False

Q. Which of the following statements is correct for cathode electrode?

1. Reduction occurs at cathode
2. Cathode has positive polarity
3. Cathode acts as a sink of electrons
4. All of the above

Q.

The catalyst used in the decomposition of hydrogen peroxide is ________

Q. Which of the following is the correct use of potassium dichromate?

1. It is used to catch drink and drive cases.
2. It is used in leather industry
3. It is used in volumetric analysis.
4. All of the above.

Q. The peroxide effect in anti-Markovnikov addition involves

1. The heterolytic fission of the double bond
2. The homolytic fission of the double bond
3. A free-radical mechanism
4. An ionic mechanism

Q. Finely divided metals and metal oxides on reaction with hydrogen peroxide liberate __ gas.

Q. Finely divided metals and metal oxides on reaction with hydrogen peroxide liberate __ gas.