English Medium इयत्ता १० - CBSE Question Bank Solutions for Science

Which of the following is true for an unbalanced chemical equation?

Which of the following is Not True with respect to the neutralisation reaction?

Before burning in air, the magnesium ribbon is cleaned by rubbing with sand paper to:

In a chemical reaction between sulphuric acid and barium chloride solution the white precipitates formed are of:

A chemical reaction does not involve:

It is necessary to balance a chemical equation in order to satisfy the law of:

When ferrous sulphate is heated strongly it undergoes decomposition to form ferric oxide as a main product accompanied by a change in colour from:

Magnesium ribbon is rubbed before burning because it has a coating of ____________.

Name the products formed when iron filings are heated with dilute hydrochloric acid.

Which of the following correctly represents a balanced chemical equation?

Why is it important to balance a skeletal chemical equation?

Assertion: In an open circuit, the current passes from one terminal of the electric cell to another.

Reason: Generally, the metal disc of a cell acts as a positive terminal.

Solid calcium oxide reacts vigorously with water to form calcium hydroxide accompanied by liberation of heat. This process is called slaking of lime. Calcium hydroxide dissolves in water to form a solution called lime water. Which among the following is (are) true about slaking of lime and the solution formed?

1.  It is an endothermic reaction
2.  It is an exothermic reaction
3. The pH of the resulting solution will be more than seven
4. The pH of the resulting solution will be less than seven

Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of the reaction involved?

1. Displacement reaction
2. Precipitation reaction
3. Combination reaction
4. Double displacement reaction

Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is

Which of the following is(are) an endothermic process(es)?

1. Dilution of sulphuric acid
2. Sublimation of dry ice
3. Condensation of water vapours
4. Evaporation of water

In the double displacement reaction between aqueous potassium iodide .and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?

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

The following reaction is used for the preparation of oxygen gas in the laboratory

`2"KClO"_3("s") overset("Heat")underset("Catalyst")(->) 2"KCl"("s") + 3"O"_2 ("g")`

Which of the following statement(s) is(are) correct about the reaction ?

Which one of the following processes involve chemical reactions?