What is meant by homologous series of organic componds? Write the chemical formula of two membres of a homologous series and state which part determines the
chemical properties of these compounds.

Write the names and symbols of two most reactive metals belongiong to group I of the periodic table. Explain by drawing electronic structure how either one of the two metals reacts with halogen. With which name is the bond formed between these elements known and what is the class of the compuond so formed known? state any four physical properties of such compounds.

Identify the compound of calcium which is yellowish white powder and is used for disinfecting drinking water. Write its chemical name and formula. How is it manufactured? Write the chemical equation for the reaction involved. Also list two other uses of the compound.

A compound which is prepared from gypsum has the property of hardening when mixed with a proper quantity of water. Identify the compound. Write the chemical equation for its preparation. For what purpose is its used in hospitals?

In nature, metal A is found in free state while state metal B is found in the form of its compounds. Which of these two metals will be near the top of the reactivity series?