Carbon and its Compounds Test - 6

The functional group present in ethanol (C₂H₅OH) is the alcoholic group (-OH group). The hydroxyl group attached to a carbon atom is known as alcohol group.

The next homologue of C₅H₁₁COOH (Pentanoic acid) is C₆H₁₃COOH (Hexanoic acid). Two adjacent homologues in a series differ by 1 carbon atom and 2 hydrogen atoms i.e. by a CH₂ group.

Ethanol (C₂H₅OH) is used for antifreeze mixture. Antifreeze is an additive which lowers the freezing point of a water-based liquid. At room temperature, ethanol is a polar solvent and is used as antifreeze.

3 structural isomers are possible for pentane (C₅H₁₂). These are n-pentane, iso-pentane and neo-pentane.

A soap molecule is said to have a tadpole structure. It consists of 2 parts - a long hydrocarbon chain which is water-repellent (hydrophobic) and an ionic part which is water-attracting (hydrophillic) due to the polar nature of water molecules.

Soap is made by heating animal oil or vegetable oil with concentrated sodium hydroxide solution. Castor oil and NaOH are the ingredients for making soap. Similarly, cotton seed oil and KOH, and mustard oil and NaOH are also the ingredients for making soap.

Reduction is the process of removal of oxygen and/or addition of hydrogen.

Ethanol (C₂H₅OH) is a cleaner fuel. It is used as a fuel in cars along with petrol. It is also used as a fuel in spirit lamps.

All of these produce hydrogen on reacting with metals. 

Metal + Water --> Metal hydroxide + Hydrogen; Metal + Steam --> Metal oxide + Hydrogen (only those metals displace hydrogen from water (or steam) which are above hydrogen in the reactivity series.

Metal + Acid --> Metal salt + Hydrogen; 

2C₂H₅OH + Na --> 2C₂H₅ONa + H₂ (This reaction is used as a test for ethanol) 

Hardness of water is caused by magnesium and calcium salts. Calcium and magnesium dissolved in water are the two most common minerals that make water hard. Temporary hardness is a type of water hardness caused by the presence of dissolved bicarbonate minerals (calcium bicarbonate and magnesium bicarbonate).