Question

1 g Mg was burnt in a closed vessel containing 2 g oxygen. Which of the following statements are not correct ? A) 0.25 g Mg left unburnt B) 1.33 g O2 left unreacted C) 2.5 g Mg will be formed D) The mixture at the end will weigh 3 g

Answer 1

Answer:

i think,

b)

Explanation:

Answer 2

The incorrect statements are:

(A) 0.25 g Mg left unburnt.

(C) 2.5 g MgO will be formed.

(D) The mixture at the end will weigh 3 g.

- The burning  of Mg in oxygen is given as:

2 Mg + O2 → 2 MgO

⇒ 48 gm Mg reacts with 32 gm of oxygen to produce 80 gm of MgO.

⇒ 1 gm Mg will react with 0.67 gm of oxygen to produce 1.67 gm of MgO.

- Here, Mg will be completely burnt.

- The amount of oxygen left = 2 - 0.67 = 1.33 gm

- Finally, 1.67 gm of MgO is formed.

- So, only option (B) is correct and all other options are incorrect.