Following experiments were carried out separately in chemistry laboratory in different test tubes, labelled as (I), (II), (III) and (IV) :-
(I) Mg + dil. HCl (II) $Al +$ dil. $H_{2} SO_{4}$
(III) Cu + dil. HCl (IV) $Mn + (2%)$ dil. $HNO_{3}$
She observed hydrogen gas is not produced in :

Question

Following experiments were carried out separately in chemistry laboratory in different test tubes, labelled as (I), (II), (III) and (IV) :-

(I) Mg + dil. HCl (II) $Al +$ dil. $H_{2} SO_{4}$

(III) Cu + dil. HCl (IV) $Mn + (2%)$ dil. $HNO_{3}$

She observed hydrogen gas is not produced in :

TestHub · Accepted Answer

Hydrogen gas is produced when metals react with dilute non-oxidizing acids.

(I) $Mg + 2HCl \to MgC l_{2} + H_{2}$ → H₂ gas produced

(II) $Al + dil. H_{2} S O_{4} \to A l_{2} (S O_{4})_{3} + H_{2}$ → H₂ gas produced

(III) Cu does not react with dil. HCl because Cu is below hydrogen in the activity series.

(IV) $Mn + 2% dil. HN O_{3}$ produces H₂ due to very dilute nitric acid.

Correct Answer: (C) Only test tube (III)

Chemistry - Complete d-block Question with Solution | TestHub