Explanation

Answer:

D

The permanant hardness cannot be removed even if it is boiled. The permanent hardness of  water can be removed by the gun's palm tit method, ion exchange resin method, and cleaning soda method. This means that the permanent hardness of water cannot be removed with boiling water.

Explanation

Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents and catalysts.

Explanation

Explanation

Plaster of Paris is made by heating the mineral gypsum. When gypsum is heated to about 150°C it losses water and produces the powder of plaster of Paris.

Explanation

Coal tar is a thick dark liquid which is a by-product of the production of coke and coal gas from coal.

It has both medical and industrial uses.

Explanation

In 1980, the World Health Organization announced the global eradication of smallpox.

It is the only human disease to be eradicated worldwide.

Explanation

Explanation

Answer:

Radionuclides (or radioactive substances) are a type of chemical substance whose atomic nucleus is unstable. They achieve stability through nuclear fission (spontaneous fission, emission of alpha particles, or conversion of neutrons to protons, or vice versa).

Explanation

MRI, and the detailed images it produces, has been a huge benefit for the study of the brain.

Its greatest innovation is allowing us to see which parts of the brain have been damaged while a patient is still alive.

Explanation

A vertebrate is an animal with a spinal cord surrounded by cartilage or bone.

  Vertebrates include birds, fish, amphibians, reptiles, and mammals.