(i) Why is drop of a liqui
d spherical in shape ?
(ii) Define Entropy.
Hydrogen occurs mainly in the combined state and is th
abundance on the earth. It forms 0.15% of the earth's cr
Answer the following questions on the basis of above par
(i) Name the isotopes of Hydrogen.
(ii) What is the atomic number of Hydrogen ?
State and explain the law of multiple proportions.
Why size of cation is smaller than size of parent atom ?
. Differentiate between e.m.f. and potential difference.
Explain the following:
Answers
Explanation:
i) Raindrops take up the spherical shape due to the surface tension of water which is caused due to the tendency of water molecules to stick together. The spherical shape is having the least possible surface area due to which it can resist any of the external force in the atmosphere.
ii) Entropy, the measure of a system's thermal energy per unit temperature that is unavailable for doing useful work.
iii) 1. There are three isotopes of the element hydrogen: hydrogen, deuterium, and tritium.
2. One (1) is the atomic number of hydrogen.
iv) Law of multiple proportions, statement that when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.
v) Cations are the atoms or molecules which have lost one or more electrons giving a net posture charge on the atom or molecule. ... Hence, there is a net posture charge, and atom is not neutral anymore. Therefore, because of this loss of electron in forming a cation, the size of the cation is smaller than its parent atom.
vi) EMF is the energy per unit charge exerted by an energy source. Potential difference is the energy released when the unit quantity of electricity passes from one point to another. The full form of EMF is Electromotive force. ... Voltage developed by an electrical source is called electromotive force.