The site of photosynthesis in the cells of a leaf is

The number of pairs of sex chromosomes in the zygote of a human being is

The most abundant metal in the earth's crust is

The poorest conductor of heat among metals is

In the Space Station the value of 'g' is only ______less than its value on the surface of Earth.

________ Predicted the existence of gravitational waves in 1916.

The number of electrons in the outermost shell of alkali metals is _________.

When sodium hydroxide reacts with sulphuric acid _________.

Formula for electric power = _______.

The law of octaves was given by ______.

_______ is used in baloons and in scuba diving.

During Newland's time _____ elements were known.

Noble gases belongs to group _____ in the modern periodic table.

Halogens belongs to group ______ in the modern periodic table.