HELLO RANJIT THE quick answer is 2
Reason Alpha particle involves the ejection of alpha particle from nucleus> since the alpha particle is a helium nucleus which involves the loss of 2 protons and 2 neutrons. now as a result if atom losses an alpha particle then it losses it mass by 4(2 protons,2 neutrons) and losses its atomic no by (2 protons) the identity of element also changes!!
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Question : Beta rays emitted by a radioactive material are
Option 1: The electrons orbiting around the nucleus
Option 2: Charged particles emitted by the nucleus
Option 3: Neutral particles
Option 4: Electromagnetic radiations
Question : Which of the following statements is correct?
Option 1: Atomic radius increases across a period and decreases down a group in the periodic table.
Option 2: Atomic radius decreases across a period and increases down a group in the periodic table.
Option 3: Atomic radius decreases across a period and down a group in the periodic table.
Option 4: Atomic radius increases across a period and increases down a group in the periodic table.
Question : The mercury and sodium street lamps light up because of:
Option 1: Atomic emission
Option 2: Atomic absorption
Option 3: Electron emission
Option 4: Electron absorption
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