Class 10 Science Chemistry Diagram basaed Questions

         DIAGRAM BASED QUESTIONS 

     CHEMISTRY

    Chemical Reactions And Equations 

Q1. 

Analyse the experiment expressed in the above figure. The molecular formulae of the solution ‘Y’ that gives a yellow colour precipitate by reacting with KI solution and the another product that forms here respectively are.

(A) Pb(NO3)2 and KNO3   

(B) PbI2 and KNO3

(C) Pb(NO3)2 and KI

(D) Pb(NO3)2 and K2SO4  

Ans: (B) PbI2 and KNO3

Q2. What is the reason for the formation of brown coloured fume in the experiment shown through the below given figure?

Ans:

The brown coloured fumes are due to the formation of Nitrogen dioxide (NO2) gas.

Q3. Analyse the activity depicted in the figure given below. In this activity, when ferrous sulphate crystals are heated does the colour and crystalline nature of it remain same or not ? Support your answer with reason. 

Ans:

★ colour and crystalline nature change.

★ due to loss of water of crystallisation

Q4. The emission of brown fumes in the given experimental set-up is due to:

(a) thermal decomposition of lead nitrate which produces brown fumes of nitrogen dioxide.

(b) thermal decomposition of lead nitrate which produces brown fumes of lead oxide.

(c) oxidation of lead nitrate forming lead oxide and nitrogen dioxide. 

(d) oxidation of lead nitrate forming lead oxide and oxygen.

Ans: (a) thermal decomposition of lead nitrate which produces brown fumes of nitrogen dioxide.

Q5. Study the experimental set-up shown in the diagram and write a chemical equation for the chemical reaction involved. Name and define the type of reaction. List two other metals that can be used in place of iron to show the same type of reaction with copper sulphate solution.

Ans: 

★ Fe(s) + CuSO4 (aq) → FeSO4(aq) + Cu(s)

★ Displacement reaction: A reaction in which a more reactive metal displaces a less reactive metal from its salt solution.

★ Other metals that can be used in place of iron to show the same type of reaction with copper sulphate solution: Zinc, Aluminium, Calcium, Magnesium.

Q6. A student performs the following experiment in his school laboratory. List two observations to justify that in this experiment a chemical change has taken place. 

Ans:

★ Bubbles of hydrogen gas are evolved when zinc granules react with dilute sulphuric acid.

★ The test tube becomes warm, showing that heat is produced - an exothermic chemical reaction has taken place.

Reaction:

Zn + H2SO4→ ZnSO4+ H2

Q7. Study the figure given below and answer the following questions:

(A) Name the process depicted in the diagram.

(B) Write the composition of gases collected at the anode and cathode. 

(C) Write the balanced chemical equation of the reaction taking place in this case. 

(D) The reaction does not take place if a few drops of dilute sulphuric acid are not added to water. Why?

Ans:

(A) Electrolytic decomposition of water/ electrolysis of water.

(B) The gas collected at cathode is hydrogen which is double the volume of oxygen collected at anode.

(C) The balanced chemical equation for the reaction is: 2H20 → 2H2+ 02 

(D) The reaction does not occur without dilute sulphuric acid because: Water is a poor conductor of electricity.

• Adding sulphuric acid improves conductivity, allowing the reaction to proceed.

     Metals And Non Metals 

Q1: (a) Observe the following diagram showing an experiment to determine the conditions under which a metal 'M' corrodes.

Ans:

Observations:

★ Test tube A: The metal 'M' rusts (corrodes) because both moisture and air are present. Corrosion needs both water and oxygen.

★ Test tube B: The metal 'M' does not rust because oil forms a barrier that prevents air reaching the metal surface. Moisture may be present but oxygen from air is excluded.

★ Test tube C: The metal 'M' does not rust because the air is dry (calcium chloride absorbs moisture) and there is no water to support corrosion.

★ Reason: Corrosion of iron-like metals requires both oxygen and moisture; absence of either prevents rusting.

★ Galvanisation: In galvanisation a thin coating of zinc is applied to iron. Zinc acts as a sacrificial metal - it corrodes preferentially and protects the iron beneath. Even if the zinc coating is scratched, zinc will corrode first and thereby protect the iron.

Q2.

Seema took a small amount of copper powder in a china dish and heated it. What changes will she observe on heating? When H2 gas is passed over this heated substance, what visible changes will be seen in it? Give the chemical equations of the reactions involved, along with the names and colours of the products in each case. 

Ans: 

★ Colour of copper powder changes from brown to black.

★ On passing H gas, the colour turns brown.

2Cu + O2 → 2CuO

(copper oxide - Black)

Cuo +H₂ → Cu + H2O

(copper - Brown)

    Acids, Bases And Salts 

Q1. Analyse the given figure. Which gas is liberated in the test tube A ? Name the precipitate X' that forms in the test tube B having lime water. 

Ans: 

 ★ Gas: Carbon dioxide (CO₂) 

★ Precipitate X: Calcium carbonate (CaCO₃) 

Q2: In the experimental setup given below, it is observed that on passing the gas produced in the reaction in the solution 'X' the solution 'X' first turns milky and then colourless.

The option that justifies the given observation is that 'X' is aqueous calcium hydroxide and:

(a) it turns milky due to carbon dioxide gas liberated in the reaction and after some time it becomes colourless due to the formation of calcium carbonate.

(c) it turns milky due to the passing of carbon dioxide through it. It turns colourless as on further passing carbon dioxide, sodium hydrogen carbonate is formed which is soluble in water.

(d) the carbon dioxide liberated during the reaction turns lime water milky due to the formation of calcium hydrogen carbonate and after some time, it turns colourless due to the formation of calcium carbonate which is soluble in water.

Ans:

(b) it turns milky due to the formation of calcium carbonate and on passing excess of carbon dioxide it becomes colourless due to the formation of calcium hydrogen carbonate which is soluble in water.

Read the following passage and answer the questions that follow:

Q3. In the given diagram, when electricity is passed through an aqueous solution of a common salt, a substance 'Z' is produced, along with the evolution of gases 'X' and 'Y'. When a burning matchstick is brought near the gas 'Y', it burns with a pop sound, whereas 'X' is used for disinfecting drinking water. When 'X' is passed through slaked lime, an insoluble substance 'A' is produced. 

Ans: 

★ X - Chlorine gas; Y - Hydrogen gas

Q4. In which case/cases will the bulb glow considering that all other connections of electric circuit are complete and working?

(A) Case (i) only 

(B) Case (ii) only 

(C) Cases (ii) and (iii) 

(D) Case (iii) only

Ans: (D) Case (iii) only

Q5. The warning sign shown in the given figure must invariably be displayed/pasted on the containers which contain hydroxide of:

(a) Aluminium

(b) Calcium

(c) Sodium

(d) Magnesium

Ans: (c) Sodium

Concentrated sodium hydroxide (NaOH) is a strong base that is highly corrosive. It can cause severe burns and must therefore be stored in containers displaying a warning sign for corrosive substances.

    Carbon And It's Compounds 

Q1. Another structure with the same molecular formula of the compound in the following structural formulas 

Ans: (D)

Q2. Correct the following incorrect electron dot structure of an unsaturated hydrocarbon and rewrite,

Ans:

Q3. Consider the structures 'X' and 'Y' given below: 

Which of the following statements are correct?

(i) 'X' and 'Y' are homologues.

(ii) 'X' and 'Y' have the same structural formula, but different molecular formula.

(iii) 'X' and 'Y' have the same molecular formula, but different structural formula.

(iv) 'X' and 'Y' are structural isomers.

(A) (i) and (iii)

(B) (i) and (iv)

(C) (ii) and (iv)

(D) (iii) and (iv)

Ans: (D) (iii) and (iv)

Q4. Select from the following the members of same homologous series: 

Ans: (1) and (4)

Q5. The structural formula of Cyclohexane is

Ans: (b)

Q6. Consider the structures of the three cyclic carbon compounds (I), (II) and (III) given below and select the correct option from the following:

(a) (I) and (III) are isomers of hexane and (II) is benzene.

(b) (I) is an isomer of hexane, (II) is benzene and (III) is an isomer of hexene.

(c) (I) is a saturated cyclic hydrocarbon and (II) and (III) are unsaturated cyclic hydrocarbons.

(d) (I) is cyclohexane and (II) and (III) are the isomers of benzene. 

Ans: (c)

Q7. Which of the following are correct structural isomers of C4H10?

(a) (I) and (III)

(b) (II) and (IV)

(c) (I) and (II)

(d) (III) and (IV)

Ans: (c)