HSC Science कक्षा १२ - Tamil Nadu Board of Secondary Education Question Bank Solutions

Which one of the following reduces tollens reagent.

The reagent used to distinguish between acetaldehyde and benzaldehyde is ____________.

A carbonyl compound A having molecular formula C₅H₁₀O forms crystalline precipitate with sodium bisulphate and gives positive iodoform test. A does not reduce Fehling's solution. Identify A.

Insulin, a hormone chemically is ___________.

Give two differences between Hormones and vitamins.

What are hormones? Give examples.

Write the Zwitter ion structure of alanine.

A complex in which the oxidation number of the metal is zero is ____________.

Schottky defect in a crystal is observed when

The cation leaves its normal position in the crystal and moves to some interstitial position, the defect in the crystal is known as ____________.

Assertion: due to Frenkel defect, density of the crystalline solid decreases.

Reason: in Frenkel defect cation and anion leaves the crystal.

The crystal with a metal deficiency defect is ____________.

What are point defects?

Explain the Schottky defect.

Write short note on metal excess and metal deficiency defect with an example.

Write a note on Frenkel defect.

The half life period of a radioactive element is 140 days. After 560 days, 1 g of element will be reduced to

After 2 hours, a radioactive substance becomes `(1/16)^"th"` of original amount. Then the half life ( in min) is

Define half life of a reaction.

Show that for a first order reaction half life is independent of initial concentration.