science test

Q1. A. Fill in the blanks.
1.      The formula of chloride of metal M is MCl2. The metal M belongs to group ___.
2.      ____ group in the periodic table contains elements that are all gases at room temperature.
3.      The arrangement of elements in a group of three is known as ­______.
4.      The chemical formula of POP is _________.
5.      The chemical reaction during which H2(g) is lost is termed as _________.
6.      Corrosion can be prevented by using __________.

B. Explain the following terms:
1.      Rancidity
2.      Endothermic reactions
3.      Redox reaction
4.      Neutralization

Q2. Give scientific reasons.
1.      Atomic size increases down the group.
2.      Metallic character decreases from left to right in a period.

Q3. Answer the following
1.      How could the modern periodic table remove various anomalies of Mendeleev’s periodic table?
2.      What is the importance of a chemical equation?
3.      What do you observe when H2S gas is passed through Cadmium Chloride solution? Name the type of reaction.
4.      Grills of doors and windows are always painted before they are used.
5.      Potassium Ferrocyanide is stored in dark coloured bottles and kept away from sunlight.

Q4. We feel fresh while on a morning walk in natural surroundings. Why don’t we feel the same after 10 a.m. and during rush hours? Write a chemical reaction to support you statement?