Question

Which of the following two combinations are correct?
Metal Gas Evolved
(i) Copper Yes
(ii) Iron Yes
(iii) Magnesium No
(iv) Zinc Yes

Answer 1

Answer:

the question is incomplete

but i am also a 10th grader so i find this question in sample paper

d) ii and iv

Explanation:

since metal react with HCL (Acid) ---> salt + H2

Cu+ HCL --> No reaction

because Cu is less reactive than H

Fe+HCL---> FeCl2 +H2

Mg+HCl----->MgCl2 + H2

but in question it is said that no gas will evolve so

it will get eliminated

Zn+HCl----->ZnCl2 + H2

that why ii and iv

hope you will mark me brainliest

Answer 2

Option (ii) and (iv) are correct.

Explanation:

• Most metals react with acids, to evolve gas. But some metals are too unreactive.

The Reaction of metal with dilute acids in the order of most reactive to least reactive:

1. Potassium, Sodium- Violent reaction
2. Sodium, Calcium, Magnesium- Rapid bubbling
3. Magnesium, Aluminium, zinc - Rabid bubbling but slow at first
4. Zinc, Iron, Tin- Slow bubbling  
5. Lead, Copper- Very slow bubbling
6. Copper, Silver, Gold, Platinum- No reaction

Here, from our options,

(i) Copper does not react with acids because it is under the no reaction and very slow bubbling category.

(ii) Iron reacts with acids to liberate hydrogen gas because it has a slow bubbling reaction.

(iii) Magnesium reacts with acids to liberate hydrogen gas because it has a rabid bubbling.

(iv) Zinc reacts with acids to liberate hydrogen gas it also has very slow bubbling.

Thus from the above options (ii) and (iv) are correct.