Question

which of the following is a type of heterogeneous mixture? salt + water oil oil + water (h₂o)

Explanation:

1. First, recall the definition of a heterogeneous mixture: a mixture where the components are not uniformly distributed and can be visually distinguished.

• Salt + water: When salt dissolves in water, it forms a homogeneous solution (the salt is uniformly dispersed, and you can't see separate salt and water phases).
• Oil: Oil is a pure substance (or a homogeneous mixture of hydrocarbons), not a mixture of different substances in a heterogeneous way here (the option "oil" is likely a single - phase substance).
• Oil + water ($\ce{H_2O}$): Oil and water do not mix uniformly. Oil is less dense than water, so they form two distinct layers (you can see the separate oil phase and water phase), which fits the definition of a heterogeneous mixture.

Answer:

oil + water ($\ce{H_2O}$) (the checkbox next to "oil + water ($\ce{H_2O}$)" should be selected)