Acids, Bases and Salts — Science STD 10 — Question

An electric iron is rated at 230V, 750W. Calculate,

1. The maximum current.
2. The number of units of electricity it would use in 30 minutes.

What can best method be used for the safe disposal of hospital wastes?

List any four characteristics of biogas on account of which it is considered an ideal fuel.

“Nervous and hormonal systems together perform the function of control and coordination in human beings.” Justify the statement.

A thick wire is hanging form a wooden table. An anticlockwise magnetic field is to be produced around the wire by passing current through this wire by using a battery. Which terminal of the battery should be connected to the:

1. Top end of wire?
2. Bottom end of wire?

Give reason for your choice.

What is the difference between the two asexual methods of reproduction: fission and fragmentation?

Write the names and formulae for the first three members of the homologous series of chloroalkanes.

Why do stars twinkle?

From the standpoint of atomic structure, what determines which element will be the first and which the last in a period of the periodic table?

"Industrialisation has adversely deteriorated the environment." Give four reasons in support of this statement.