Laboratory Method

Q.

What is combination reaction.Give three examples.

Q. Carbon reacts with oxygen to give carbon dioxide. This is an example of:

1. Double displacement reaction
2. Decomposition reaction
3. Displacement reaction
4. Combination reaction

Q.

Is lime water an acidic or basic solution?

Q.

An acidic buffer is obtained on mixing

1. $100mL$ of $0.1M$ $\mathrm{HCl}$ and $200mL$ of $0.1M$ ${\mathrm{CH}}_3\mathrm{COONa}$

2. $100mL$ of $0.1M$ $\mathrm{HCl}$ and $200mL$ of $0.1M$ $\mathrm{NaCl}$

3. $100mL$ of $0.1M$ ${\mathrm{CH}}_3\mathrm{COOH}$ and $100mL$ of $0.1M$$\mathrm{NaOH}$

4. $100mL$ of $0.1M$ ${\mathrm{CH}}_3\mathrm{COOH}$ and $200mL$ of $0.1M$ $\mathrm{NaOH}$

Q.

(a) Draw a labelled diagram for the laboratory preparation of hydrogen chloride gas.
(b) Give the balanced equation for the reaction.
(c) Name the drying agent used in drying hydrogen chloride gas.
(d) Phosphorus pentoxide and calcium oxide are good drying agents but they cannot be used to dry hydrogen chloride gas. Why?

Q.

Which of the following is the chemical formula for muriatic acid?

1. H₂SO₄

2. HNO₃

3. HCl

4. NaCl

Q.

What do you mean by ionizable hydrogen atoms?

Q. Arrange increasing order of acidic character? HClO3, HBrO3, HIO3, HClO, HBrO, HIO

Q.

Hydrogen chloride gas is very soluble in water. It is dissolved in water to prepare hydrochloric acid by using an anti-suction device, as shown in the diagram. Very briefly explain, how this device prevents the suction of water into the flask, in which hydrogen chloride gas is produced.

Q.

Is ${\mathrm{SO}}_3$ soluble in water?

Q.

When Sodium chloride is heated with concentrated Sulphuric acid below $200°\mathrm{C}$, one of the products formed is ……….. . (sodium hydrogen sulphate / sodium sulphate / chlorine )

Q.

Conc. sulphuric acid is used as it is non volatile and has a high boiling point.

1. False

2. True

Q. 15mL of water and 10mL of sulphuric acid are to be mixed in a beaker.
(I) state the method that should be followed with reason.
(II) what is the process called?

Q.

How do you classify acids as strong and weak acids

Q. Drying agents like calcium oxide and phosphorus pentoxide are not used for drying hydrogen chloride gas. Give reasons for each. [2 MARKS]

Q.

What is the chemical formula of oxalic acid and citric acid?

Q.

The given set up in the figure is for the preparation of an acid.
(a) Name the acid prepared by this method.
(b) Name the reactants used.
(c) Why is an empty flask used?
(d) What is the drying agent used? Why is this drying agent chosen?
(e) What is the role of the inverted funnel in the arrangement?

Q.

Write a combination reaction in which two gases combine.

Q.

How are Oxygen and Carbon dioxide prepared in the laboratory?

Q. (a) Why is high temperature avoided in the preparation of hydrogen chloride from sodium sulphate and concentrated sulphuric acid?
(b) Sodium chloride is preferred for the preparation of HCI. Why? [2 MARKS]

Q.

While preparing hydrochloric acid back suction can be avoided by

1. carefully placing the delivery tube immersed in water

2. special funnel arrangement immersed in water

3. special funnel arrangement just touching the water surface.

4. Back suction cannot be avoided

Q.

A reaction of direct combination, i.e. synthesis in which two gases combine to give another gas, turns lime-water milky.

Q.

"Downward displacement of air" is a method of

1. collection of HCl gas

2. purification of HCl gas

3. identification of HCl gas

4. preparation of HCl gas

Q. 22. Which of the following is most acidic in nature?(1) SO(2) Al2O3(3) CO(4) P2O5

Q.

What will be the behaviour of the compound having the molecular formula ${\mathrm{NH}}_2{\mathrm{CH}}_2\mathrm{COOH}$:?

Q.

In using sulphuric acid to prepare other acids, as mentioned above, which property of sulphuric acid is used?

Q. 11.Which one of the following is the most acidic in character ? (1) CH3CHO (2) CH3COCH3 (3) CH3COOC2H5 (4) CH3NO2

Q.

Which of the following statement(s) is are correct?

i. An inverted funnel arrangement is used in the laboratory preparation of hydrochloric acid.

ii. HCl gas is insoluble in water.

1. i only

2. ii only

3. Both i and ii

4. All the statements are wrong.

Q.

Write a combination reaction involving two gases.

Q.

Dilute hydrochloric acid and dilute sulfuric acid are both colourless solutions.

How will the addition of barium chloride solution to each help to distinguish between the two?