The Peiodic Table — CHEMISTRY STD 9 — Question

Metals like …………….. , ……………… and ……………… give H2 with steam.
(iron, magnesium, aluminium, sodium, calcium)

A metal …………….. hydrogen in the activity series gives hydrogen with …………… acid or …………… acid.
(above, below, dilute hydrochloric, concentrated hydrochloric, dilute sulphuric).

The chemical properties of an element are the periodic function of their ________

Almost all the mass of an atom concentrated in a small space within the atom, is called __________

An atom is electrically __________ Such that the total __________ charge on the nucleus, is equal to total  __________ charge of electrons.

Lanthanide are the elements from atomic number 57 to ________and are placed ________the periodic table.

Moving left to right in the second period, the number of valence electrons _____.

All protons are identical and have a charge equal to __________ coulombs.

An atom has the mass number 35 and the atomic number 17. The number of neutrons in its nucleus are  __________