(English Medium) ICSE Class 10 - CISCE Important Questions

Draw the electron dot structure for the following:

A molecular nitrogen

[At. No. : N = 7, H = 1]

Draw the electron dot structure of Methane molecule.

[Atomic number: N = 7, C = 6, H = 1]

Draw the electron dot structure of Nitrogen molecule.

[Atomic number: N = 7, C = 6, H = 1]

Give reason for the following:

Covalent compounds have a low melting and boiling point.

Carbon tetrachloride is a ______ covalent molecule.

The following table shows the electronic configuration of the atoms A, B, C and D.

1. Write the formula of the compound formed between:
   
   1. A and B
   2. D and C
2. Which of the above elements will exhibit catenation?

Write a balanced chemical equation for the reaction of sodium hydroxide solution with iron (III) chloride solution

Three solutions P, Q and R have pH value of 3.5, 5.2 and 12.2 respectively. Which one of these is a:

1) Weak acid?

2) Strong alkali?

 State one observation for each of the following  :
 A small piece of zinc is added to dilute hydrochloric acid 

Give the appropriate term defined by the statements given below :
 The substance that releases hydronium ion as the only positive ion when dissolved in water. 

 Name the particles present in :
 Weak electrolyte 

The metal that will not produce hydrogen gas when reacted with dilute acids.

Identify the substance underlined, in the following case

A solid formed by reaction of two gases, one of which is acidic and the other basic in nature

Write a balanced chemical equation for the following:

Preparation of methane from iodomethane.

Write a balanced chemical equation for the preparation of the following salts

Copper carbonate 

State what would you observe when Washing Soda Crystals are exposed to the atmosphere

State what would you observe when The salt ferric chloride is exposed to the atmosphere

Identify the anion present in the following compounds:

A salt D on treatment with dilute sulphuric acid produces a gas which turns lime water milky but has no effect on acidified potassium dichromate solution

Identify the anion present in the following compounds:
When barium chloride solution is added to salt solution E a white precipitate insoluble in dilute hydrochloric acid is obtained.

From the list of the following salts choose the salt that most appropriately fits the description is given in the following:

[AgCl, MgCl₂, NaHSO₄, PbCO₃, ZnCO₃, KNO₃, Ca(NO₃)₂]

An insoluble chloride.