PDF chapter test TRY NOW

1. Identify the changes involved in the following processes as physical or chemical changes.(d) Curdling of milk.
 
Curdling milk is a change that results in the formation of a new product called curd, which has a composition that differs from milk.
 
2. During the reaction of some metals with dilute hydrochloric acid, following observations were made.
Explain these observation giving suitable reason.
(d) Some bubbles of a gas are seen when lead (Pb) is reacted with the acid.
  
When lead reacts with , gas bubbles are formed.
 
\(Pb\)(s) + \(2HCl\)(aq) → \(PbCl_2\)​(aq) + \(H_2\)​(g)