P-1 Effects of electric current — Science STD 10 — Question

1. Give the names and formulae of one metal chloride and one non-metal chloride.
2. State an important property in which these metal chloride and non-metal chloride differ.
3. Why do they differ in this property?

State the uses/applications of an electric motor.

Identiry the electronic configuration of the Inert gas elements, third row elements, seventeen group elements, second group elements:
(i) (2, 8, 2), (ii) (2, 8, 8), (iii) (2, 8, 1), (iv) (2, 7), (v) (2, 2), (vi) (2, 8), (vii) (2, 8, 7).

Write what the signs indicate:

What are the constituents of acid rain? What are its two effects on earth's surface ?

Take a rectangular cardboard with two holes. Take a coil of large numbers of turns. Insert the coil through the holes such that the turns are normal to the plane of the cardboard. Connect two ends of the coil in series with battery, a key and a rheostat as shown in figure 5.15. Sprinkle iron filings uniformly on the cardboard. Plug the key, tap the cardboard gently. Note your observations.

Give three examples of each: Physical problems arising due to excessive use of mobile phones.

Some of the important fossils which have been studied are those of organisms X, Y and Z. X were marine arthropods which were common between 400 to 600 million years ago. Y were the invertebrate animals (molluscs) with a flat, coiled, spiral shell which lived in the sea about 180 million years ago. Z are the extinct carnivorous or herbivorous reptiles which appeared on the earth about 250 million years ago and became extinct about 65 million years ago. What are X, Y and Z?

Observe the following diagram and write answers.

1. Name the method.
2. Write anode reaction and cathode reaction.
3. Why fluorspar and cryolite are added in the mixture?