Question

identify the type of chemical reaction given here: c₂h₄(g) + 3o₂(g) → 2co₂(g) + 2h₂o(g) options: synthesis, double displacement, complete combustion, incomplete combustion which of the following expressions best describes the term net ionic equation? options: an equation where all reactants and products are ions, an equation listing all ions that are not spectator ions, an equation where soluble substances are written in dissociated form, an equation where only reactants are written in dissociated form

Explanation:

First Question (Identify the type of chemical reaction)

• A synthesis reaction combines simpler substances to form a more complex one (e.g., \(A + B \to AB\)), which does not match the given reaction (\(C_2H_4 + O_2 \to CO_2 + H_2O\)).
• A double - displacement reaction involves the exchange of ions between two compounds (e.g., \(AB+CD\to AD + CB\)), and the given reaction does not follow this pattern.
• In a complete combustion reaction of a hydrocarbon (like \(C_2H_4\), an alkene), the hydrocarbon reacts with oxygen (\(O_2\)) to produce carbon dioxide (\(CO_2\)) and water (\(H_2O\)) as products. The reaction \(C_2H_4(g)+3O_2(g)\to 2CO_2(g)+2H_2O(g)\) produces \(CO_2\) and \(H_2O\), which is characteristic of complete combustion. In incomplete combustion, carbon monoxide (or carbon) and water are produced, which is not the case here.

Second Question (Define net ionic equation)

• A net ionic equation is not an equation where all reactants and products are ions. Some reactants or products may be in molecular form (e.g., insoluble solids, weak electrolytes).
• A net ionic equation is derived by removing spectator ions (ions that appear unchanged on both sides of the ionic equation) from the total ionic equation. So, it lists only the ions that are involved in the chemical change, i.e., the ions that are not spectator ions.
• An equation where soluble substances are written in dissociated form is a total ionic equation, not a net ionic equation.
• A net ionic equation includes both reactants and products (in ionic or molecular form for non - ionic species), not just reactants in dissociated form.

Answer:

C. complete combustion