Questions

True, The luster of a metal is due to presence of free electrons. Luster means shine or soft glow. We know that metals have the quality of reflecting light from its surface.

23 chromosomes are in a human gamete.

Human somatic cells have 46 chromosomes(23 pairs) but a gamete(germ cell) gets half the amount, i.e. 23 chromosomes, (one from each pair). There will be half the number of chromosomes an organism has in its somatic cells (all other body cells except gametes).

For example in humans, the somatic cells contain 46 chromosomes which are the diploid number (2n) and each sperm and egg has 23 chromosomes where one of them is the sex chromosome.

The main group number for an element can be found from its column on the periodic table. For example, carbon is in group 4 and has 4 valence electrons. Oxygen is in group 6 and has 6 valence electrons.

The scientific study of rocks is called petrology, which is an essential component of geology.

The IT ministry launched a desktop software e-Aksharayan in a conference for Indian Languages Technology Industry 'Bhashantara', in New Delhi. The objective is to enable editing and printing of text in scanned documents. The software e-Aksharayan was launched in 7 Indian languages.