CBSE Class X – Science Chemistry Exam (Full Syllabus)

Which reaction takes place when layer of silver deposit on copper wire when dipped in silver nitrate solution?

Identify the reducing agent in the following reactions: 2H₂ + O₂ → 2H₂O

Which of the following gases can be used for the storage of fresh sample of an oil for a long duration?

Dilute hydrochloric acid is added to granulated zinc taken in a test tube. The following observations are recorded. Designate the accurate observation:

Which of the subsequent does show an oxidation reaction

Calcium phosphate is present in tooth enamel. Its nature is:

If 10 mL of H₂SO₄ is mixed with 10 mL of Mg(OH)₂ of the same concentration, the resultant solution will give the following colour with universal indicator:

Which among the following is not a base?

Common salt other than being used in kitchen can also be used as the raw material for  making:

1. Washing soda
2. Bleaching powder
3. Baking soda
4. Slaked lime

Name the acid along present in ant sting

An element X with atomic number 12 forms a compound with element Y with atomic number 17. The formula of the compound formed is:

The element with atomic number 14 is hard and forms acidic oxide and a covalent halide. To which of the following classification does the element belong?

Which one of the following does not increase while moving down in group of the  periodic table?

Arrange the following elements in increasing order of their atomic radii:

Arrange the following elements in the order of their increasing non-metallic character Li, O, C, Be and F

Buckminsterfullerene is an allotropic form of:

The property of self-linkage among identical atoms to form long chain compounds is known as:

The number of covalent bonds in the molecule of ethane.

Unsaturated hydrocarbon undergoes incomplete combustion and burns with

Rich conductors of electricity.

An element A is mushy and can be cut with a knife. This is very reactive to air and cannot be kept in open air. It reacts vigorously with water. Identify the element from the following:

2 ml each of conc. HCl, HNO₃, and a mixture of conc. HCl and conc. HNO3 in the ratio of 3:1 were taken in test tubes labelled as : A, B and C. A small piece of metal was put in each test tube. No change occurred in test tubes A and B but the metal got dissolved in test tube C. The metal could be:

1. AI
2. Au
3. Cu
4. Pt

Name one non-metal that exist in liquid state at room temperature.

Name two metals having melting point less than 310 K (37°C).

When a metal X is treated with cold water, it gives a basic salt Y with molecular formula XOH (molecular mass = 40) and liberates a gas Z which easily catches fre. Identify X, Y and Z.