STD X – METALLURGY – EINSTEIN

Metals and Non-Metals.

Elements can be categorised in to metals and non-metals.

Metallurgy deals with the extraction of metals from their ores and purify it for use. A substance called flux is added to the ore to take out the impurities.

Metals are the elements that have an inclination to lose electrons and form positively charged ions. Most of elements found in our environment are metals.

Metals are positioned on the left and middle of the modern periodic table.

The extreme left of the periodic table consists of the  alkali metals followed by alkaline earth metals, transition metals. Inner transition metals are positioned below  the periodic table in two rows.

Non-metals are elements that have an inclination to accept electrons to form negatively charged ions.

Reactivity series

As mentioned in the introduction, the activity series of metals is a list of metals ranked in order of decreasing reactivity to displace hydrogen gas from water and acid solutions.

Taking non-metal hydrogen as the reference, metals placed below hydrogen in the activity series cannot replace hydrogen from the diluted acids. On the other hand, the metals placed above hydrogen in the activity series can replace the other metals below from its salt solution.

Extraction of Metals based on the Activity series

Metals occur naturally as carbonates, sulphides, oxides or halides in the earth’s crust and these are called minerals. If it is economically viable to extract the metal from the mineral it is called an ore. Thus all ores are minerals but all minerals are not ores.

Use of Metals and Alloys

Metals are the elements that have the inclination to lose electrons and form positively charged ions. An alloy is a homogeneous(meaning similar) metallic solution comprised of two or more elements.