Carbon and its Compounds Test - 7

Butane C₄H₁₀ has 3 C-C covalent bonds and 10 C-H covalent bonds. Thus, it has 13 covalent bonds.

Butanone (CH₃COCH₂CH₃) is the second member of ketones. It is a four carbon compound with ketone functional group (- CO -). The ketone functional group has two free valencies which are satisfied by one methyl ( -CH₃ )  group and one ethyl ( -C₂H₅ ) group.

The odour of ethanoic acid (CH₃COOH) resembles vinegar. A dilute solution of ethanoic acid in water is called vinegar. Vinegar contains about 5 to 8 % ethanoic acid.

Sodium stearate (C₁₇H₃₅COONa) is chemically a sodium salt of stearic acid (C₁₇H₃₅COOH). Stearic acid (IUPAC name - Octadecanoic acid) is a saturated fatty acid with an 18-carbon chain. Soaps are sodium or potassium salts of long chain fatty acids.

Freezing point of pure ethanoic acid is 16.6 °C (61.9 °F). Freezing point of pure water is 0 °C. Freezing point of pure ethyl alcohol (C₂H₅OH) is -114.1 °C. Freezing point of pure acetone is -95 °C. When ethanoic acid (acetic acid) is cooled below 10 °C, it freezes to form a colourless, ice-like solid. The solid looks like glacier and hence pure ethanoic acid is called glacial ethanoic acid (or glacial acetic acid).

The esters are found naturally in fruits like apples, pears, bananas, pineapples, and strawberries. Fruits exhibit their aroma due to the presence of esters. Hence, it is said that esters have a fruity smell. Esters are also present in vegetables. CH₃COOC₂H₅ is an ester.

A brisk effervescence of carbon dioxide gas will be observed when ethanoic acid reacts with solid sodium bicarbonate. This reaction is used is a test for ethanoic acid.

CH₃COOH + NAHCO₃ --> CH₃COONa + H₂O + CO₂

Soap is basic in nature. Acid dyes are used to dye protein fibers such as silk, wool, angora, mohair, feathers, etc. Hence, soap doesn’t work well with woolen garments. The soap gets neutralised by the acidic dyes.

Invertase helps in breaking sucrose into its component parts - glucose and fructose. Zymase converts starch into glucose. Diastase transforms starch into maltose and after that it converts it into glucose. Maltase is an enzyme that can break down disaccharide maltose.