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Two elements 'A' and 'B' were burnt in air in two separate jars. The ash formed by their burning was mixed with water to form two separate solutions. Both the solutions turned red litmus blue. Also, on reacting elements 'A' and 'B' with dilute HCL element 'A' produced bubbles of a colourless gas, whereas element 'B' did not react. Which of the following statements is correct about elements 'A' and 'B'?
The correct answer is 'A' and 'B' are metals; and 'A' is more reactive than 'B'.Concept:Chemical reaction:It is a process in which one or more substances, the reactants, are converted to one or more different substances, the products.A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.Bases:They are bitter in taste and soapy to touch.They turn red litmus blue.They have a pH value greater than 7.Explanation:Solution is basic because it turned red litmus blue.When a substance burns in the air, it reacts with oxygen and forms oxides.Oxides when mixed with water form hydroxides. A substance that turns red litmus blue is basic in nature. Metal oxides and hydroxides are basic in nature. So, elements A and B must be metals. Some reactive metals react with dilute acids like HCl to form salts and hydrogen gas is released in the process. Thus, A will be more reactive than B since it reacts with dilute acid while B does not.
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