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

24 cc Marsh gas (CH₄) was mixed with 106 cc oxygen and then exploded. On cooling the volume of the mixture became 82 cc, of which, 58 cc was unchanged oxygen. Which law does this experiment support? Explain with calculations.

What volume of oxygen would be required to burn completely 400 ml of acetylene [C₂H₂]? Also calculate the volume of carbon dioxide formed.

\[\ce{2C2H2 + 5H2O -> 4CO2 + 2H2O(l)}\]

1250 cc of oxygen was burnt with 300cc of ethane [C₂H₆]. Calculate the volume of carbon dioxide formed:

\[\ce{2C2H6 + 7O2  -> 4CO2 + 6H2O}\]

What volume of propane is burnt for every 500 cm³ of air used in the reaction under the same conditions? (assuming oxygen is `1/5`th of air)

\[\ce{C3H8 + 5O2 → 3CO2 + 4H2O}\]

450 cm³ of nitrogen monoxide and 200 cm³ of oxygen are mixed together and ignited. Caclulate the composition of resulting mixture.

\[\ce{2NO + O2 → 2NO2}\]

If 6 liters of hydrogen and 4 liters of chlorine are mixed and exploded and if water is added to the gases formed, find the volume of the residual gas.

Ammonia may be oxidised to nitrogen monoxide in the presence of a catalyst according to the following equation.

\[\ce{4NH3 + 5O2 → 4NO + 6H2O}\]

If 27 litres of reactants are consumed, what volume of nitrogen monoxide is produced at the same temperature and pressure?

A mixture of hydrogen and chlorine occupying 36 cm³ was exploded. On shaking it with water, 4 cm³ of hydrogen was left behind. Find the composition of the mixture.

What volume of air (containing 20% O₂ by volume) will be required to burn completely 10 cm³ of methane and acetylene?

\[\ce{CH4 + 2O2 → CO2 + 2H2O}\]

\[\ce{2C2H2 + 5O2 -> 4CO2 + 2H2O}\]

LPG has 60% propane and 40% butane: 10 litres of this mixture is burnt. Calculate the volume of carbon dioxide added to atmosphere.

\[\ce{C3H8 + 5O2 → 3CO2 + 4H2O}\]

\[\ce{2C4H10 + 13O2 → 8CO2 + 10H2O}\]

200 cm³ of CO₂ is collected at STP when a mixture of acetylene and oxygen is ignited. Calculate the volume of acetylene and oxygen at STP. in original mixture.

\[\ce{2C2H2_{(g)} + 5O2_{(g)} → 4CO2_{(g)} + 2H2O_{(g)}}\]

Explain the term empirical formula.

0.2 g atom of silicon combine with 21.3 g of chlorine. Find the empirical formula of the compound formed.

In a compound of magnesium (Mg = 24) and nitrogen (N = 14), 18 g of magnesium combines with 7g of nitrogen.

Deduce the simplest formula by answering the following questions:

1. How many gram-atoms of magnesium are equal to 18g?
2. How many gram-atoms of nitrogen are equal to 7g of nitrogen?
3. Calculate the simple ratio of gram-atoms of magnesium to gram-atoms of nitrogen and hence the simplest formula of the compound formed.

Give the empirical formula of C₆H₁₈O₃

112 cm³ of H₂S(g) is mixed with 120 cm³ of Cl₂(g) at STP to produce HCl(g) and sulphur(s). Write a balanced equation for this reaction and calculate

1. the volume of gaseous product formed.
2. composition of the resulting mixture.

A compound is formed by 24 g of X and 64 g of oxygen. If the atomic mass of X = 12 and O = 16, calculate the simplest formula of the compound.

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.

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; \[\ce{C}\] = 12; \[\ce{Cl}\] = 35.5)

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.