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4. Structure of the Atom I. For question numbers 1 to 8, two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a). (b), (c) and (d) as given below :   (a) Both A and R are true and R is the correct explanation of the assertion. (b) Both A and R are true butRis not the correct explanation of the assertion.   (c) A is true but R is false.   (d) A Is false but R is true. (1 Mark) 1. Assertion (A) : Electrons, protons and neutral particles (neutrons) in an atom are called 'sub-atomic particles'. Reason (R) : According to John Dalton's atomic theory, an atom can be further subdivided into three fundamental 'sub-atomic partides'. 2. Assertion (A) : JJ. Thomson explained presence of electrons by cathode rays experiment. Reason (R) : Charge on an electron is equal to - 1.6 x 10"C and mass of the electron is 9.1 x 10 kg. ...

2. Is Matter Around  Us Pure 1. For question numbers 1 to 9, two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below : (a) Both A and R are true and R is the correct explanation of the assertion. (b) Both A and R are true but R is not the correct explanation of the assertion.   (c) A is true but R is false. (d) A is false but R is true. 1. Assertion (A) : The air is a compound containing oxygen, nitrogen, argon, carbon dioxide and water vapour in a fixed proportion according to their masses. Reason (R) : A compound is a substance whose composition of the components is fixed Le; they combine together in a fixed ratio according to their masses.   2. Assertion (A) :A solution is a homogeneous mixture of two or more substances. Reason (R) : A solution has a solvent and a solute as its ...

  Matter in Our Surroundings 1.For question numbers 1 to 11, two statements are given-one labeled  Assertion (A) and the other labeled Reason (R). Select the correct answer to these questions from the codes (a), (b). (c) and (d) as given below : (a) Both A and R are true and R is the correct explanation of the assertion. (b) Both A and Rare true but R is not the correct explanation of the assertion. (c) A is true but R is false.  (d) A is false but R is true. (I Mark)  1. Assertion (A) :  Substances like sugar and salt are insoluble in water and on dissolving, they settle down at the bottom Reason (R) :  When we dissolve salt in water, the particles of salt get mixed into the spaces between the particles of water. 2. Assertion (A) :  Sponge is a solid.  Reason (R) :  Sponge can change its shape under force and regains its shape when force is removed and it breaks on applying greater force. 3. Assertion (A) :  Copper sulphate and potassi...