Question

In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature ?
(a) $\sf{2H_{2} (l) + O_{2} (l) \longrightarrow 2H_{2}O (g)}$
(b) $\sf{2H_{2} (g) + O_{2} (l) \longrightarrow 2H_{2}O (l)}$
(c) $\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (l)}$
(d) $\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (g)}$

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Answer 1

Question:

In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature ?

(a) $\sf{2H_{2} (l) + O_{2} (l) \longrightarrow 2H_{2}O (g)}$

(b) $\sf{2H_{2} (g) + O_{2} (l) \longrightarrow 2H_{2}O (l)}$

(c) $\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (l)}$

(d) $\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (g)}$

• Answer:

( c ) $\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (l)}$

• Explanation:

The Standard state of Hydrogen is gaseous (g) , also of Oxygen. While, standard state of water is liquid ( L )

• The ( l ) sign means that the substance is liquid.

• The ( g ) sign states that the compound is a gas.

• The ( aq ) sign stands for aqeouos ( means that the compound is dissolved into water )

• The ( s ) sign states that the compound is solid.

Thus, The answer to your question is Opt. C i.e $\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (l)}$

____________________________

Answer 2

Answer:-

The Correct Answer is Option ( D ).

$\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (g)}$

We usually think that, Hydrogen + Oxygen gives us Liquid Water but It's Wrong.

Hydrogen and Oxygen always Combine to form gaseous Water and release Energy.

That's why $\sf{2H_{2} (g) + O_{2} (g) \longrightarrow 2H_{2}O (g)}$

Word Equation:-

Hydrogen (g) + Oxygen (g) ------> Water (g) + Energy.

Where,

Hydrogen and Oxygen are Reactants while Water is a Product, formed by the Combination of Hydrogen and Oxygen.

Note :-

(g) means the Reactant/Product is in Gaseous State.

(l) means the Reactant/Product is in Liquid State.

( s) means the Reactant/Product is in solid State.