You have to be very careful with this question. A change in mass can also occur in chemical changes especially if you have too much of something. For example
CH4 + 1.5 02 ===> CO2 + H2O
If you have too much of either CH4 or O2, there will be some CH4 or O2 left over. There has been a change in mass that you have too much of.
However that is not the point of the question. It is just something you need to be aware of.
Suppose you have a piece of aluminum and you take a course grinder after it. You will change the texture of the side you took the grinder to. If the aluminum has been anodized (a color has been put on it's surface), you may grind the color off or if it is just plain aluminum, you may roughen the surface, but you won't change what the aluminum will do chemically.
You may need only a small portion of the aluminum and you grind off just what you need. That will change the mass of both what you took off and the piece that you want, but the aluminum will still do whatever chemical property you need to use.
So you can change both texture and mass without changing the chemical properties of the substance whose mass or texture you are changing.
Answer: option <span>D. be given a positive charge produced by the movement of electrons to the other end of the ball.
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Explanation:
This phenomenon is called electrostatic induction.
The excess of negative charge on the end of the rod will repel the electrons on the side of the pith ball that have been approached to it.
Then the electrons on the pith ball will move far away from this end with it will be left an excess of positive charge.
In this way the rod has induced that the ball acquires a positive charge on one end and a negative charge on the other end.
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The correct answer is option C
<span>alkenes donot react with potassium dichromate , but can react with potassium permanganate</span>
