OMTEX CLASSES
Q1. A. Fill in the blanks.
1.
____group in the periodic table contains
elements that are all gases at room temperature.
2.
The law used by Newlands to arrange
elements is known as_______.
3.
Elements showing properties of both
metals and non – metals are known as________.
4.
The chemical reaction during which H2(g)
is lost is termed as______.
5.
When acids and alkalis react together,
salt and ______are formed.
6.
Most of the acidic substances are _____in
taste.
7.
The strength of basic substance is
represented by_____.
8.
Acids and bases neutralize each other to
form _______and______.
9.
In FeSO4. 7H2O.H2O
represents______________.
10. Litmus
paper or solution is obtained from a plant named________.
Q2. Write short notes on
1.
Indicators
(with proper example).
2.
pH scale (with
proper diagram).
Q3. Answer the following questions.
1.
What is
universal indicator? Does Mg(OH)2 react with sodium hydroxide? If
not, why?
2.
How could the
modern periodic table remove various anomalies of Mendeleev’s periodic table?
3.
What are the
demerits of Mendeleev’s periodic table?
Q4. Give Scientific reasons.
1.
Grills of
doors and windows are always painted before they are used.
2.
Potassium
Ferrocyanide is stored in dark coloured bottles and kept away from sunlight.
3.
Edible oil is
not allowed to stand for a long time in an iron or tin container.
4.
Atomic size
increases down the group.
