Railway Science (Chemistry-Metals , Non-Metals and Alloys) (Part-III)

It has a low freezing point and a high boiling point. It has a high coefficient of thermal expansion. Due to environmental and health concerns, the use of mercury in thermometers is being phased out in many countries. Safer alternatives like alcohol or galinstan (a non-toxic alloy) are increasingly used.

Malleability refers to the ability of a metal to be hammered or pressed into thin sheets without breaking or cracking. Silver is known for its exceptional malleability, making it highly suitable for various applications, including jewelry, coins, and decorative items.

Gold and platinum are classified as noble metals, which means they are resistant to oxidation and corrosion compared to other metals. This is due to their electronic configuration, specifically the presence of filled d- and f-orbitals in their outermost energy levels. Corrosion - The degradation of metals due to an electrochemical process. The formation of rust on iron is an example of corrosion.

Atomic number - 79. It has an enormous ability to get stretched and high malleability and ductility, high thermal and electrical conductivities, resistant to corrosion. Platinum (Pt₇₈) and Silver (Ag₄₇) are also the most ductile natural metals.

Basic in nature and turn red litmus to blue. Example - Magnesium oxide (MgO), Calcium oxide (CaO), Barium oxide (BaO). Non-metallic oxides - formed when a non-metal reacts with oxygen gas.
Examples - Carbon dioxide (CO₂), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide(CO). Metal hydroxides are hydroxide of metals.They are often strong bases. Examples - Calcium hydroxide Ca(OH)₂, Sodium hydroxide (NaOH), Potassium hydroxide (KOH).

These are highly reactive alkali metals. They readily react with oxygen in the air at room temperature, releasing a significant amount of heat and often igniting spontaneously.

The property of metals by which they can be beaten into thin sheets is called malleability. The property of metal by which it can be drawn into wires is called ductility. Metals that produce ringing sounds are said to be sonorous.

Examples of non-metals are sulfur, carbon, oxygen, phosphorus, etc. The property of metals by which they can be beaten into thin sheets is called malleability. Those metals which can be drawn into wire are called ductile. Metals like sodium and potassium are soft and can be cut with a knife. Mercury is the only metal which is found in liquid state at room temperature.

According to IUPAC, transition metals are defined as metals which have an incomplete d subshell either in neutral atoms or in their ions. The period 4 transition metals are scandium (Sc₂₁), titanium (Ti₂₂), vanadium (V₂₃), chromium (Cr₂₄), manganese (Mn₂₅), iron (Fe₂₆), cobalt (Co₂₇), nickel (Ni₂₈), copper (Cu₂₉), and zinc (Zn₃₀).

Chlorine is a chemical element with symbol Cl and atomic number 17. Classified as a halogen, Chlorine is a gas at room temperature. Non-metals are the elements which form negative ions by gaining an electron.