Give a reason for each of the following:-
(i) Why is symbol S for sulphur but Si is used for silicon and Na for sodium?
(ii) Why is water considered a compound?
(iii) Why group 17 elements are reactive is nature?
(iv) Inert solvent is used for keeping sodium?
(v) Hydrogen is called as ‘inflammable air’?
Answers
Answer:
it can not be explained because it is fixed by scientists
Elements
Explanation:
(i) The symbols of elements were derived from their Latin and Greek synonyms. Latin name of sulphur is sulfur and was given the symbol S. As S is already taken by Sulphur, Silicon was assigned the symbol Si to avoid confusion. The latin name of Silicon is silex or silicis. However, Sodium was given the symbol Na based on its Latin name Natrium.
(ii) Water is a compound because it is made from more than one kind of element (oxygen and hydrogen).
(iii) Group 17 is halogens and they are highly reactive that none is found in nature as a free element.
(iv) Sodium is a very reactive metal. So it is stored using an inert solvent.
(v) Hydrogen gas is called a inflammable air as it can burn on fire to form oxide and burns with a pop sound.