Metals and Non-Metals — Science STD 10 — Question

Give reasons for the following.
Unsaturated hydrocarbons show addition reaction.

What is autonomic nervous system? What is its function?

The potential difference between the terminals of an electric iron is 240V and the current is 5.0A. What is the resistance of the electric iron?

What happens when bases react with non-metal oxides? Explain with the help of an example. What does this reaction tell us about the nature of non-metal oxides?

How many colours are there in a full spectrum of white light? Write the various colours of spectrum in the order, starting with red.

Grapes hanging on the plant do not ferment but after being plucked from the plant can be fermented. Under what conditions do these grapes ferment? Is it a chemical or a physical change?

While studying the dependence of potential difference (V) across a resistor on the current (I) passing through it, in order to determine the resistance of the resistor, a student took 5 readings for different values of current and plotted a graph between V and I. He got a straight line graph passing through the origin. What does the straight line signify? Write the method of determining the resistance of the resister using this graph.

In tobacco plant, the male gametes have 24 chromosomes.

1. What is the number of chromosomes in the female gamete?
2. What is the number of chromosomes in the zygote?

The boy walks towards the mirror at a speed of 1m/ s. At what speed does his image approach him?

Define fuel. List any two characteristics that you would look for in a good fuel.