Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions for Chemistry

The sharp melting point of crystalline solids is due to ______.

Why some glass objects from ancient civilisations are found to become milky in appearance?

Which of the following amorphous solid is used as photovoltaic material for conversion of sunlight into electricity?

“The importance of many pure substance in life depends on their composition.” Which of the following statement justify the above fact?

Which of the following fluoride is used as rat poison?

Most of the processes in our body occur in ____________.

The term homogenous mixtures signifies that ____________.

Which of the following mixture is(are) called solution?

(i) water + ammonia

(ii) water + acetone

(iii) acetone + alcohol

(iv) hexane + water

Which of the following statement is incorrect for group 15 elements?

What causes nitrogen to be chemically inert?

Nitrogen dioxide cannot be obtained by heating:

When two halogen atoms are attached to the same carbon atom then it is:

Which one of the following is non-crystalline or amorphous?

m-Xylene reacts with Br₂ in presence of FeBr₃, what are products formed:

Amorphous solids are ______.

O-hydroxy benzyl alcohol when reacted with PCl₃ gives the product as ______. (IUPAC name)

Which of the following is true about the value of refractive index of quartz glass?

Amorphous solid can also be called:

(i) pseudo solids

(ii) true solids

(iii) supercooled liquids

(iv) supercooled solids

Which of the following features are not shown by quartz glass?

(i) This is a crystalline solid.

(ii) Refractive index is same in all the directions.

(iii) This has definite heat of fusion.

(iv) This is also called super cooled liquid.

Under which situations can an amorphous substance change to crystalline form?