Question

which equation represents a synthesis chemical reaction? *
2 points
2s + 3o₂ → 2so₃
2k + 2h₂o → 2koh + h₂
2nacl → 2na + cl₂
zn + 2hcl → zncl₂ + h₂

Explanation:

A synthesis reaction is when two or more reactants combine to form a single product (A + B → AB).

• First option: \(2\text{S} + 3\text{O}_2

ightarrow 2\text{SO}_3\) has two reactants (S and \(O_2\)) forming one product (\(SO_3\)), matching synthesis.

• Second option: \(2\text{K} + 2\text{H}_2\text{O}

ightarrow 2\text{KOH} + \text{H}_2\) is a single - replacement (K replaces H in \(H_2O\)).

• Third option: \(2\text{NaCl}

ightarrow 2\text{Na} + \text{Cl}_2\) is decomposition (one compound breaks into two).

• Fourth option: \(\text{Zn} + 2\text{HCl}

ightarrow \text{ZnCl}_2 + \text{H}_2\) is single - replacement (Zn replaces H in HCl).

Answer:

A. \(2\text{S} + 3\text{O}_2
ightarrow 2\text{SO}_3\)