Consider the reaction: 2H₂ + O₂ → 2H₂O (Mr: H₂ = 2, O₂ = 32, H₂O = 18). What is the atom economy for producing water?

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Question

Consider the reaction: 2H₂ + O₂ → 2H₂O (Mr: H₂ = 2, O₂ = 32, H₂O = 18). What is the atom economy for producing water?

Accepted Answer

A) 100% — In this reaction, the only product is water, so all reactant atoms end up in the desired product. Atom economy = (2 × 18) ÷ (2 × 2 + 32) × 100 = 36 ÷ 36 × 100 = 100%. Any reaction with a single product automatically has 100% atom economy because there are no by-products.

Answer

B) 75%

Answer

C) 50%

Answer

D) 90%

Answer

A) 100%

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