Metals and Non-Metals

It is the heavy, metallic and hard tin dioxide (SnO₂). It is the major ore of tin. It is colourless when pure, but brown or black when iron impurities are present.

A metalloid is a chemical element with properties that are in between a mixture or those of metals and non-metals. It is considered to be difficult to classify unambiguously as either a metal or a non metal. Iron is a metal. So, it does not have the properties of metalloids.

Magnesium burns brightly in oxygen to form a metal oxide called magnesium oxide with the chemical formula MgO. Magnesium is a chemical that burns with a white flame. The colours are produced by the redox reaction and depend on what kind of salt or metal is burning. To produce very bright light the creator of the fireworks will use magnesium, aluminium and titanium.

All the metals are sonorous as they can produce sound. But mercury and lead are the metals, which are non ductile and non sonorous.

Silicon is the seventh most abundant element in the universe and the second most abundant element in the Earth's crust. Silicon with carbon atoms forms silicon carbide that is next to diamond in hardness and is therefore used for making tools used in grinding.

Corrosion is a gradual destruction of material usually metals by chemical reaction with its environment. This means the electrochemical oxidation of metals by reacting with an oxidant such as oxygen.

When iron nails are kept in a beaker containing copper sulphate solution, the displacement reaction takes place. As iron is more reactive than copper, it displaces copper from the copper sulphate solution. The iron nail becomes brownish in colour and the blue colour of copper sulphate solution fades. Thus, it becomes iron sulphate and copper. This copper is reddish brown in colour and precipitated at the bottom of the beaker.

All non metals do not react with water to form either metal oxides or metal hydroxides. Whether water is in the form of cold water, hot water or steam, all the non metals will remain unresponsive to the action of water. The reason for this is the typical electronic configuration of non metals. Non metals are electronegative are unable to break the bond between H and O in water. Non metals cannot reduce hydrogen by donating electrons. As carbon is a non metal, it will not react with water or steam.

Pure silver is the best conductor of heat and electricity of all the known metals. So, it is sometimes used in making solder, electrical contacts and printed circuit boards. Silver actually conducts electricity more efficiently than copper.

It is a heavy, volatile, corrosive, reddish brown, non metallic liquid element having a highly irritating vapour. Bromine is the only non metallic element that is liquid under ordinary conditions. It evaporates easily at standard temperature and pressures in a red vapour that has a strong disagreeable odour resembling that of chlorine.

Aluminium foil is made from a big block of refined (pretty pure) aluminium. Aluminium foil is aluminium prepared in thin metal leaves with a thickness less than 0.2 millimetres.

Gold is a dense, soft, shiny, malleable and ductile metal. Gold readily creates alloys with many other metals. The extreme malleability, ductility and softness of pure gold make it practically useless for jewellery applications. The addition of alloying elements (other metals) to gold is used to increase the toughness and hardness of the metal. 

Of all the metals, untarnished silver is the best reflector of light. As a result it was used in ancient times to make mirrors. Unfortunately, silver tarnishes very easily and quickly.

An insulator is a non conducting material that does not carry any charge. Electricity does not flow through insulators, which are usually non metallic. Graphite is a version of carbon and hence, is a conductor and not an insulator.

Potassium and sodium are two essential minerals used to regulate and maintain the cardiovascular system. Sodium is required for the nervous system to effectively communicate with and coordinate various parts of the body. If sodium levels are inadequate for neuronal function, then a muscle cell will fail to function properly.

When sodium is placed in water, it reacts with water and begins to melt. As a result of this reaction, sodium hydroxide and hydrogen are produced. The hydrogen produced self ignites and burns with a bright flame.

Sulphur plays an important role in the rubber industry during the process of hardening of rubber called vulcanization. Vulcanization of rubber is a process of improvement its elasticity and strength by heating it in the presence of sulphur, which results in three dimensional cross linking of the chain rubber molecules bonded to each other by sulphur atoms.

Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. Although galvanization can be done with electrochemical and electrodeposition processes, the most common method in current use is hot dip galvanization, in which steel parts are submerged in a bath of molten zinc.

Silicon carbide also known as carborundum is a compound of silicon and carbon with chemical formula SiC. In manufacturing, it is used for its hardness in abrasive machining processes, such as grinding, honing, water jet cutting and sandblasting.

Chrome orange also known as chrome red is an orange pigment, which consists of lead (II) chromate and lead (II) oxide. Chrome orange can be made by precipitating lead (II) together with chromate in a basic solution or by treating chrome yellow with dye. Chrome yellow is a kind of yellow powder and is the isomorphous crystal mixture of lead chromate and lead sulphate.

Sodium metal reacts with oxygen at room temperature to form sodium oxide. Sodium also reacts violently with water. It is so active that it is normally stored under a liquid with which it does not react. Kerosene or naphtha liquids are commonly used for this purpose. Hence, sodium is stored under kerosene to prevent its reaction with oxygen, moisture and carbon dioxide.

The metals Iike iron, lead and copper do not burn in air. Instead they get covered with an oxide layer that is insoluble in water. When copper oxidizes it forms a very thin layer of copper oxide on the outer surface of the copper that further protects the surface from oxidation. This layer is greenish in colour and is called patina.

Copper turns green, when exposed to air due to the formation of a protective layer of copper carbonate. This protective green coating is called verdigris.

The activity series is a chart of metals listed in order of declining relative reactivity. The top metals are more reactive than the metals at the bottom. Titanium is a transition element and is placed above zirconium and next to scandium.

It is because lead is less denser than mercury. Mercury is very heavy weighing 13.6 times to that of volume of water. Stone, iron, and even lead can float on its surface.

All metals are sonorous except mercury and lead. Mercury occurs in liquid state so lead is the only non sonorous metal occurring in solid state and thus exhibiting the properties of non metals.

Copper turns green when exposed to air due to the formation of a protective layer of copper carbonate called verdigris. Verdigris is a green coating or patina formed, when an alloy of copper, bronze or brass is weathered and exposed to the atmosphere or water over a long period of time. The colour of verdigris varies from shades of blue to shades of green. The simple composition of verdigris is copper carbonate and copper hydroxide,  but if verdigris is being formed at the seashore or somewhere near the sea it consists of copper chloride.

Alnico is a powerful permanent magnet alloy containing iron, nickel and aluminium. Aluminium nickel cobalt (AlNiCo) magnet alloy exhibits excellent temperature stability.

Invar also known as FeNi36 is a nickel iron alloy notable for its uniquely low coefficient of thermal expansion (CTE or ل). The name comes from the word invariable referring to its lack of expansion or contraction with temperature changes.