Materials Metals and Non Metals Test - 8

Metals generally have 1, 2 or 3 electrons in their outermost orbit or valence shell. e.g.,

(i) Sodium - (Na) - 2, 8, 1

(ii) Magnesium (Mg) - 2, 8, 2

(iii) Aluminium - (Al) - 2, 8, 3.

The number of valence electrons in sodium, magnesium and aluminium metals are 1, 2 and 3 respectively.

Non-metals generally contain 4,5,6,7 or 8 electrons in their outermost orbit or shell.

(i) Carbon 2, 4

(ii) Nitrogen 2, 5

(iii) Oxygen 2, 6

(iv) Fluorine 2, 7

The number of valence electrons in carbon, nitrogen, oxygen and fluorine are 4, 5, 6, 7 respectively.

 Elements which show the properties of both the metals and non-metals are called metalloids. e.g., antimony and arsenic

Calcium is more reactive than magnesium. Hence, Mg can be replaced from its salt by calcium.

Aluminium foil is prepared by beating it into sheets, i.e., property of malleability. Hence, aluminium foil is used for the given application.

Sulphur is yellow in colour.

  Non-metals have low densities, low melting points and are poor conductors of electricity.

Bromine is the only non-metal which exists in liquid state at room temperature.

Copper, Mercury, Silver and Gold are less reactive than hydrogen. Hence, they cannot displace hydrogen from the compounds like dilute acids, water, etc.

 Among the given metals, sodium is a highly reactive metal, so it reacts vigorously to form salt and hydrogen.  2Na + 2HCl → 2NaCl + H₂ ↑