Questions

Rainfall and addition of fresh water from rivers reduce salinity neat the coasts.

The most prominent form of Shiva in Brihadeshvara Temple built by Chola dynasty is Tripuntaka. Tripurantaka is a manifestation of the Hindu god Shiva. In this aspect, Shiva is depicted with four arms wielding a bow and arrow. Shiva as Tripurantaka is accredited with destroying three mythical cities of the Asuras. It is believed that the Rudraksha came from lord Shiva’s eyes, when he destroyed Tripura.

The rate of change of velocity is called as Acceleration.

Polarity :: 

The polarity of a molecule defines its other physical properties such as melting point, boiling point, surface tension, vapor pressure etc... Simply, polarity occurs when the electron distribution in a molecule is asymmetric. This results in a net dipole moment in the molecule. One end of the molecule is charged negative while the other gets a positive charge.

The polarization of a molecule greatly depends on the shape of the molecule. A diatomic molecule like HF mentioned above has no issue of shape. The net dipole moment is only due to the uneven distribution of electrons between the two atoms. However, when there are more than two atoms involved in making a bond, there are many complexities.

The water molecule is of bent shape. Therefore, when the two pair of electrons shared by oxygen with two hydrogen atoms is pulled towards oxygen, the net dipole moment results in the direction of the oxygen atom. There is no other force to cancel out the resultant dipole moment. Hence, the water molecule is highly polar.

Ammonia molecule is of a pyramid shape and the electronegative N atom pulls the electrons towards itself. The three N-H bonds are not in the same plane; hence the dipole moments created do not get canceled out. This makes ammonia a polar molecule.

However, the dipole moments sometimes get canceled due to the shape of the molecules, making the molecule non-polar. Carbon dioxide is such a molecule.

An omnivore is an animal that eats food from both plants and animals.

Animals that eat other animals are called carnivores. Carnivores that eat herbivores are called secondary consumers, and carnivores that eat other carnivores are called tertiary consumers.