Out of aphelion and perihelion, where is the speed of the earth more and why?

A satellite is in an elliptic orbit around the earth with aphelion of 6R and perihelion of 2R where R = 6400 km is the radius of the earth. Find eccentricity of the orbit. [G = 6.67 xx 10^-11 SI units and M = 6xx 10^24 kg]

Out of white phosphorus and red Phosphorus, which one is More reactive and why?

Out of phenol and benzene which is more easily nitrated and why ?

Out of alcohol and water, which one is more acidic and why?

The speed of sound waves depends on temperature but speed of light waves does not, why?

What is more elastic : water or air, why?

Out of ethylamine and ammonia which is more basic and why?

The escape speed of a projectile on the earth’s surface is 11.2 km s^-1 . A body is projected out with thrice this speed. What is the speed of the body far away from the earth? Ignore the presence of the sun and other planets.