Question

please answer these questions, i am really sorry for troubling you :( i just need help with these:

1. Write word equation
a. Magnesium oxide dissolves in water , it forms Magnesium
Hydroxide
b. Zinc oxide reacts with Carbon to give Zinc and Carbon
monoxide
2. Write the chemical formula for rust. What are the two important
conditions necessary for Rusting?
3. Why freezing of water is considered as a physical change?
4. What are the changes observed when iron metal is placed in
copper sulphate solution?
5. Why it is advised that spoon should not be placed in pickle
jar?
6. Define the terms: a. endothermic and exothermic reactions.
b. Crystallisation
7. How is an element, compound and mixture different form each
other? Give examples for each.
8. Write the chemical formula (with steps) for the following -
a. Copper chloride
b. Zinc oxide
c. Magnesium Sulphide
d. Calcium Hydroxide
9. What the difference in 2X and X2.
10.What is the difference between the smallest particle of an element
and the smallest particle of a compound.
11.Write the symbols of: Calcium, Potassium, Silver, Magnesium,
Phosphate, Hydroxide, Gold and Aluminium.
12. What do you mean by water table in a water cycle?
13.List the reasons for depletion of water table.
14.Define: a) Infiltration b)ground water
15. If we keep on drawing water from underground, how will it
affect the water table?
16. Name the process by which ground water is discharged?

Answer 1

hope it will help you

Answer 2

Physical change :- No new substance is formed.

Chemical change :- New substance is formed.

Example :- Burning of candle is both a physical and chemical change.