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

Explain the term:

Gram mole

Explain the term: 

Mole

What do you understand by the term mole? How many elementary units are in one mole of a substance?

Fill in the blank
One gram atom of an element contains ______ atoms.

Fill in the blank.
One a.m.u. is the mass of ______ atom of C^₁₂.

Fill in the blank
 Avogadro's number is equal to ______

Calculate the number of molecules in 12.8g of sulphur dioxide gas. Take Avogadro's number as 6 x 10²³.
[S = 32, 0 = 16 ]

Calculate the weight of one molecule of oxygen.

[Avogadro’s number = 6 × 10²³, O = 16 ]

Two oxides of a metal (M) have 20.12% and 11.19% oxygen. The formula of the first oxide is MO. Determine the formula of the second oxide.

A student puts his signature with graphite pencil. If the mass of carbon in the signature is 10^-12 g. Calculate the number of carbon atoms in the signature.

A flask contains 3.2g of sulphur dioxide.Calculate the following : The moles of sulphur dioxide present in the flask.

Given that the relative molecular mass of copper oxide is 80, what volume of ammonia (measured at STP) is required to completely reduce 120g of copper oxide? The equation for the reaction is :
3CuO + 2NH₃ → 3Cu + 3H₂O + N₂

Calculate the number of moles and number of molecules present in 1.4 g of ethylene gas. What is the volume occupied by the same amount of ethylene?

A sample of ammonium nitrate when heated yields 8.96 litres of steam (measured at STP)
NH₄NO₃ → N₂O + 2H₂O
What volume of dinitrogen oxide is produced at the same time as 8.96 L of steam?

A sample of ammonium nitrate when heated yields 8.96 litres of steam (measured at STP)
NH₄NO₃ → N₂O + 2H₂O
What mass of ammonium nitrate should be heated to produce 8.96L of steam?

A sample of ammonium nitrate when heated yields 8.96 litres of steam (measured at STP)
NH₄NO₃ → N₂O + 2H₂O
Determine the percentage of oxygen in the ammonium nitrate?

The equation for the burning of octane is:

\[\ce{2C8H18 + 25O2 -> 16CO2 + 18H2O}\]

1. How many moles of carbon dioxide are produced when one mole of octane burns?
2. What volume, at STP, is occupied by the number of moles determined in (a)?
3. If the relative molecular mass of carbon dioxide is 44, what is the mass of carbon dioxide produced by burning moles of octane?
4. What is the empirical formula of octane?

Correct the following statement :
Equal masses of all gases under identical conditions contain the same number of molecules.

Calculate the mass of 0.1 mole of carbon dioxide.

[Atomic mass: S = 32, C = 12 and O = 16 and Avogadro's number = 6 × 10²³]

Complete the following calculations. Show working for complete credit :
Calculate the mass of calcium that will contain the same number of atoms as are present in 3.2 gm of Sulphur. [Atomic masses : S = 32, Ca = 40]