English Medium कक्षा १० - CBSE Question Bank Solutions

A food chain comprising birds, green plants, fish and man. The concentration of harmful chemical entering the food chain will be maximum in ______.

Which of the following is a logical sequence of food chain?

Which of the following is an autotroph?

Magnetic lines of force inside current carrying solenoid are ____________.

Food chains are very important for the survival of most species.

If 10,000 J solar energy falls on green plants in a terrestrial ecosystem, what percentage of solar energy will be converted into food energy?

Food chains are very important for the survival of most species.

Matter and energy are two fundamental inputs of an ecosystem. Movement of:

Observe the food web and answer the questions given below:

Why do all food chains start with plants?

Which of the following is not a physical change?

The following reaction is an example of a `4"NH"_3("g") + "SO"_2 -> 4"NO"("g") + 6"H"_2"O"("g")`

1. displacement reaction
2. combination reaction
3.  redox reaction
4. neutralisation reaction

Which of the following statements about the given reaction are correct?

`3"Fe"("s") + 4"H"_2"O"("g") -> "Fe"_3"O"_4("s") + 4"H"_2("g")`

1.  Iron metal is getting oxidised
2. Water is getting reduced
3. Water is acting as reducing agent
4.  Water is acting as oxidising agent

Which of the following are exothermic processes?

1. Reaction of water with quick lime
2. Dilution of an acid
3. Evaporation of water
4.  Sublimation of camphor (crystals)

Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of NaOH, anhydrous CuSO₄ and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solutions contained in beakers A and B, whereas in case of beaker C, the temperature of the solution falls. Which one of the following statement(s) is(are) correct?

1.  In beakers A and B, exothermic process has occurred.
2. In beakers A and B, endothermic process has occurred.
3. In beaker C exothermic process has occurred.
4.  In beaker C endothermic process has occurred.

A dilute ferrous sulphate solution is gradually added to the beaker containing acidified permanganate solution. The light purple colour of the solution fades and finally disappears. Which of the following is the correct explanation for the observation?

Which among the following is(are) double displacement reaction(s)?

1. `"Pb" + "CuCl"_2 -> "PbCl"_2 + "Cu"`
2. `"Na"_2"SO"_4 + "BaCl"_2 -> "BaSO"_4 + 2"NaCl"`
3. `"C" + "O"_2 -> "CO"_2`
4. `"CH"_4 + 2"O"_2 -> "CO"_2 + 2"H"_2"O"`

Which among the following statement(s) is(are) true? ‘Exposure of silver chloride to sunlight for a long duration turns grey due to

1. The formation of silver by the decomposition of silver chloride.
2. sublimation of silver chloride.
3. decomposition of chlorine gas from silver chloride.
4. oxidation of silver chloride.

Give the characteristic tests for the following gases :

1. CO₂
2. SO₂
3. O₂
4. H₂

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

Although metals form basic oxides, which of the following metals form an amphoteric oxide?

A molecule of ammonia (NH₃) has

Which of the following are correct structural isomers of butane?

1. \[\begin{array}{cc}
   \ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\\
   |\phantom{....}|\phantom{....}|\phantom{....}|\\
   \ce{H - C - C - C - C - H}\\
   |\phantom{....}|\phantom{....}|\phantom{....}|\\
   \ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\\
   \end{array}\]
   
   
2. \[\begin{array}{cc}
   \ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\\
   |\phantom{....}|\phantom{....}|\\
   \ce{H - C - C - C - H}\\
   |\phantom{.....}|\phantom{.....}|\\
   \ce{H}\ce{H-C-H}\ce{H}\\
   |\\
   \ce{H}\\
   \end{array}\]
3. \[\begin{array}{cc}
   \ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\\
   |\phantom{....}|\phantom{....}|\\
   \ce{H - C - C - C - H}\\
   |\phantom{.....}\backslash\phantom{..}|\\
   \phantom{....}\ce{H}\phantom{......}\ce{C - H}\phantom{}\\
   \phantom{.......}|\\
   \phantom{.......}\ce{H}\\
   \end{array}\]
4. \[\begin{array}{cc}
   \ce{H}\phantom{...}\ce{H}\\
   |\phantom{....}|\\
   \ce{H - C - C - H}\\
   |\phantom{....}|\\
   \ce{H - C - C - H}\\
   |\phantom{....}|\\
   \ce{H}\phantom{...}\ce{H}\\
   \end{array}\]