(English Medium) ICSE Class 10 - CISCE Question Bank Solutions

Silicon (Si = 28) forms a compound with chlorine (Cl = 35.5) in which 5.6 g of silicon combines with 21.3 g of chlorine. Calculate the empirical formula of the compound.

1. A compound has the following percentage composition by mass: carbon 14.4%, hydrogen 1.2% and chlorine 84.5%. Determine the empirical formula of this compound. Work correctly to 1 decimal place. (H = 1; C = 12; Cl = 35.5)
2. The relative molecular mass of this compound is 168, so what is its molecular formula?
3. By what type of reaction could this compound be obtained from ethyne?

The reaction: \[\ce{4N2O + CH4 -> CO2 + 2H2O + 4N2}\] takes place in the gaseous state. If all volumes are measured at the same temperature and pressure, calculate the volume of dinitrogen oxide (N₂O) required to give 150 cm³ of steam.

The volumes of gases A, B, C and D are in the ratio, 1 : 2 : 2 : 4 under the same conditions of temperature and pressure.

1. Which sample of gas contains the maximum number of molecules?
2. If the temperature and pressure of gas A are kept constant, then what will happen to the volume of A when the number of molecules is doubled?
3. If this ratio of gas volume refers to the reactants and products of a reaction, which gas law is being observed?
4. If the volume of A is actually 5.6 dm³ at STP, calculate the number of molecules in the actual Volume of D at STP (Avogadro's number is 6 × 10²³).
5. Using your answer from (iv), state the mass of D if the gas is dinitrogen oxide (N₂O).

Write the balanced equation for the reaction of dilute hydrochloric acid with the following:

Iron

Write the balanced equation for the reaction of dilute hydrochloric acid with the following:

Sodium hydrogen carbonate

Write the balanced equation for the reaction of dilute hydrochloric acid with the following:

Iron (II) sulphide

Write the balanced equation for the reaction of dilute hydrochloric acid with the following:

Magnesium sulphite

Write observation:

Lead nitrate solution is mixed with dilute hydrochloric acid and heated.

Write observation:

A small piece of zinc is added to dilute hydrochloric acid.

Lead nitrate decomposes on heating to give ______.

X, Y and Z are three crystalline solids that are soluble in water and have a common anion.

To help you to identify X, Y and Z, you are provided with the following experimental observations. Copy and complete the corresponding inferences in (a) to (e).

1. A reddish-brown gas is obtained when X, Y and Z are separately warmed with concentrated sulphuric acid and copper turning added to the mixture.
   INFERENCE 1: The common anion is the ______ ion.
2. When X is heated, it melts and gives off only one gas which re-lights a glowing splint.
   INFERENCE 2: The cation in X is either ______ or ______.
3. The action of heat on Y produces a reddish-brown gas and yellow residue which fuses with a glass of the test tube.
   INFERENCE 3: The metal ion present in Y is the ______ ion.
4. When Z is heated, it leaves no residue. Warming Z with sodium hydroxide solution liberates a gas which turns moist red litmus paper blue.
   INFERENCE 4: Z contains the ______ cation.
5. Write the equations for the following reactions:
   1. X and concentrated sulphuric acid (below 200°C). (One equation only for either of the cations given in INFERENCE 2)
   2. The action of heat on Y.
   3. Concentrated nitric acid is added to copper turnings kept in a beaker.

Write the equation for the reaction of dilute nitric acid with copper.

Explain why only all-glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate.

Explain why nitric acid is kept in a reagent bottle for a long time.

The figure given below illustrates the apparatus used in the laboratory preparation of nitric acid.

1. Name A (a liquid), B (a solid), and C (a liquid). (Do not give the formulae.)
2. Write an equation to show how nitric acid undergoes decomposition.
3. Write the equation for the reaction in which copper is oxidised by concentrated nitric acid.

A dilute acid B does not normally give hydrogen when reacted with metals but does give a gas when it reacts with copper. Identify B. Write the equation with copper.

Complete the table:

What is the property of nitric acid which allows it to react with copper?

From the following list of substances, choose one substance in the case which matches the description given below:

Ammonium nitrate, calcium hydrogen carbonate, copper carbonate, lead nitrate, potassium nitrate, sodium carbonate, sodium hydrogen carbonate, zinc carbonate.

A Substance that gives off only oxygen when heated.