HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Important Questions

Give a scientific reason:

The pyramid of energy is always upright.

What is Red Data Book?

Dodo bird, stellar sea cow and passenger pigeon are few examples of extinction due to ______.

Select the odd example with respect to types of conservation strategies. 

A medicinal plant Rauwolfia vomitoria shows variations in concentration of reserpine from location to location. What type of level of biodiversity is this?

Write full form of

1. IUCN
2. NBA

Give any four factors that favour high speciation at lower altitudes.

With the help of any one example explain Alien species invasion as one of the causes of Biodiversity losses.

How many atoms constitute one unit cell of a face-centered cubic crystal?

What is the formula of a compound in which the element Y forms hcp lattice and atoms of X occupy 2/3^rd of tetrahedral voids?

Define the following term: Primitive unit cells

Define the following term:

Ferromagnetism

Define Anisotropy.

Define Anisotropy.

An element with molar mass 27 g/mol forms a cubic unit cell with edge length of 405 p.m. If the density of the element is 2.7 g/cm³, what is the nature of the cubic unit cell?

Draw diagram of bcc unit cell.

Define unit cell.

Define unit cell.

Gold crystallises into face-centred cubic cells. The edge length of a unit cell is 4.08 × 10^–8 cm. Calculate the density of gold. [Molar mass of gold = 197 g mol^–1]

Define isomorphism.