CLASS-VII

CHEMICAL SUBSTANCES AND PROCESSES

WORKSHEET-1

Q1. Fill in the blanks:

a)     Burning of wood in air converts it into ___________ and __________.

b)    Copper articles get coated with a green substance on exposure to ___________.

c)     Chemical name of common salt is ____________________.

d)    Chemical name of limestone is ____________________.

e)     CaO is also called ________________.

f)      Combination of nitrogen and hydrogen gas gives ___________ gas.

g)     __________ is the chemical formula of glucose.

Q2. Name any two:

a)     positive ions

b)    negative ions

Q3. Observe the diagram carefully and answer the following questions:

( for diagram, refer worksheet given in class)

a)     Name the reaction.

b)    Write the chemical equation for the reaction.

c)     Name the element which deposits as a brown coating.

Q4. What happens when electric current is passed through water? Write chemical equation also.

Q5. Write the chemical formula of the following:

a)     Magnesium sulphate

b)    Calcium oxide

c)     Aluminium hydroxide

d)    Zinc phosphate