Science (086) — AI-generated practice question

When copper powder is heated in air, oxygen is added to it, forming black copper(II) oxide.

Chemical equation:

$$2\text{Cu} + \text{O}_2 \xrightarrow{\text{Heat}} 2\text{CuO}$$

Type of reaction: It is an oxidation reaction (copper gains oxygen). It can also be classified as a combination reaction (two substances combine to form one product).

Source: Chapter 1, Section 1.2.5 Oxidation and Reduction

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• Examiners expect the balanced equation with the heat condition arrow — missing this loses a mark.
• Two valid type-labels are acceptable: oxidation (because Cu gains oxygen) and combination (two reactants → one product). Writing either or both is fine; writing both shows depth.
• The key term is copper(II) oxide — "copper oxide" alone may be accepted but the IUPAC name is preferred.