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

State what do you observe when:
Neutral litmus solution is added to alkaline solution

Write the observation, and balanced equation for the following reaction:
Sodium hydroxide is added dropwise to a solution of zinc sulphate, till it is in excess.

Identify the substance Q based on the information given below:
The white crystalline solid Q is soluble in water. It liberates a pungent smelling gas when heated with sodium hydroxide solution.

Choose the correct answer from the options given below :
Hydroxide of this metal is soluble is sodium hydroxide solution

State Gay-Lussac's law of combining volumes.

How does Avogadro's law explain Gay - lussac's law of combining volumes?

Explain the terms empirical formula and molecular formula.

Give the empirical formula of C₆H₆.

Give the empirical formula of: C₆H₁₂O₆

Give the empirical formula of C₂H₂

Give the empirical formula of CH₃COOH

Give example of compound whose:
Empirical formula is the same as the molecular formula.

Give example of compound whose:
Empirical formula is different from the molecular formula.

A compound of lead has following percentage composition, Pb = 90.66%, O = 9.34%. Calculate empirical formula of a compound. [Pb = 207, O = 16]

A compound contains 87.5% by mass of nitrogen and 12.5% by mass of hydrogen. Determine the empirical formula of this compound.

Calculate the empirical formula of the compound having 37.6% sodium, 23.1% silicon and 39.3% oxygen.(Answer correct to two decimal places) (O = 16, Na = 23, Si = 28)

The empirical formula of a compound is C₂H₅. Its vapour density is 29. Determine the relative molecular mass of the compound and hence its molecular formula.

The compound A has the following percentage composition by mass: C =26.7%, O = 71.1%, H = 2.2%.
Determine the empirical formula of A.(Answer to one decimal place)  (H=1,C=12,O=16)

Water can split into hydrogen and oxygen under suitable conditions. The equations representing the change is:  2H₂O(I) → 2H₂ (g) + O₂(g)
If a given experiment results in 2500cm³ of hydrogen being produced, what volume of oxygen is liberated at the same time under the same conditions of temperature and pressure?

Determine the empirical formula of the compound whose composition by mass is 42% nitrogen, 48% oxygen and 9% hydrogen.[N=14,O=16,H=1]