Homogeneous Mixture Examples in Chemistry

Start with the recap, study the fully worked examples, then use the practice problems to check your understanding of Homogeneous Mixture.

This page combines explanation, solved examples, and follow-up practice so you can move from recognition to confident problem-solving in Chemistry.

Concept Recap

A mixture with a completely uniform composition throughout, where the components are evenly distributed at the molecular level and cannot be distinguished even under a microscope (also called a solution).

It looks the same everywhere. You can't see the separate parts, even under a microscope.

Read the full concept explanation →

How to Use These Examples

Read the first worked example with the solution open so the structure is clear.
Try the practice problems before revealing each solution.
Use the related concepts and background knowledge badges if you feel stuck.

What to Focus On

Core idea: Homogeneous Mixture asks what the sample is, what property is being used, and whether a new substance is formed.

Common stuck point: Students often know a formula related to homogeneous mixture but skip the recognition step: Am I classifying matter or using properties, state, particle behavior, or mixture evidence to describe a sample? That leads to a correct-looking substitution attached to the wrong chemical model.

Sense of Study hint: Ask: Am I classifying matter or using properties, state, particle behavior, or mixture evidence to describe a sample?

Worked Examples

Example 1

easy

Define a homogeneous mixture and explain how it differs from a heterogeneous mixture. Give two examples of each.

Answer

\text{Homogeneous: uniform (salt water, air). Heterogeneous: non-uniform (oil/water, granite).}

First step

A homogeneous mixture has a uniform composition throughout — any sample taken from it has the same proportions of components. Examples: salt water, air.

Full solution

2
A heterogeneous mixture has a non-uniform composition — different regions have different proportions. Examples: oil and water, granite.
3
The key distinction is uniformity at the macroscopic level: homogeneous mixtures look the same throughout, while heterogeneous mixtures show visible differences.

Homogeneous mixtures are also called solutions. The particles in a homogeneous mixture are so small (molecular or ionic level) that they cannot be seen and do not settle out over time.

Example 2

medium

Is air a homogeneous mixture or a pure substance? Justify your answer and list its major components with approximate percentages.

Example 3

medium

A student dissolves

20\,\text{g}

of NaCl in

80\,\text{g}

of water until the solution is clear. (a) What kind of mixture is this? (b) What is the mass percent of NaCl?

Example 4

medium

A solution contains

15\,\text{g}

of sugar in

135\,\text{g}

of water. Find the mass percent of sugar.

Example 5

medium

Brass is

70\%

Cu and

30\%

Zn by mass. What mass of Cu is in a

250\,\text{g}

brass coin?

Example 6

hard

500\,\text{mL}

saline solution has a NaCl concentration of

0.90\,\text{g}/100\,\text{mL}

. How much NaCl is dissolved?

Example 7

hard

A homogeneous mixture is

5.0\%

NaCl by mass. What mass of NaCl is in

120\,\text{g}

of solution?

Practice Problems

Try these problems on your own first, then open the solution to compare your method.

Example 1

medium

A student dissolves

10

g of sugar in

100

mL of water and stirs until clear. Is this a homogeneous or heterogeneous mixture? How could the student confirm this experimentally?

Example 2

hard

Bronze is a solid homogeneous mixture (alloy) of copper and tin. Explain why bronze is classified as a homogeneous mixture rather than a compound, even though it is a solid.

Cu and Sn atoms uniformly arranged — bronze is a homogeneous solid alloy, not a compound

Example 3

easy

Is salt water (fully dissolved) a homogeneous mixture?

Particles of Na⁺ and Cl⁻ (two species) uniformly mixed in liquid water — a homogeneous mixture

Example 4

easy

Is air (a mix of

N_2

O_2

, etc.) a homogeneous mixture?

N₂ and O₂ molecules (two species) uniformly distributed in the gas phase — air is a homogeneous mixture

Example 5

easy

Example 26

medium

Classify each: (a) saline (NaCl in water), (b) milk, (c) gasoline, (d) chicken soup.

Example 27

medium

Why is air, even though it contains

\text{N}_2

\text{O}_2

, Ar, and

\text{CO}_2

, called a homogeneous mixture?

Example 28

medium

Is steam (pure water vapor) a homogeneous mixture or a pure substance?

Example 29

medium

Is a soft drink (carbonated, sealed bottle) a homogeneous mixture?

Example 30

easy

Is gasoline (a mix of hydrocarbons) a homogeneous mixture?

Example 31

medium

Distinguish: solute, solvent, and solution. Which is the homogeneous mixture?

Example 32

hard

If you take three different drops from a homogeneous sugar–water solution and analyze each, what do you expect for the mass percent of sugar?

Every drop from this solution contains the same ratio of solute (sugar) to solvent (water) — uniform composition throughout

Example 33

hard

Explain how distillation can separate a homogeneous mixture of ethanol and water even though they look identical.

Example 34

medium

Is sea water before any solids settle a homogeneous mixture?

Example 35

easy

Is solid sterling silver (

92.5\%

Ag,

7.5\%

Cu) a homogeneous mixture?

Example 36

medium

Compare salt water (homogeneous) and a sand-and-water mixture (heterogeneous). Which physical method separates each?

Example 37

hard

Why does adding too much sugar eventually make sugar water heterogeneous?

Example 38

challenge

Soda fountain syrup is mixed with carbonated water in a

1:5

ratio by volume to make a drink. Assuming both inputs are homogeneous and the mixing is complete, is the drink homogeneous? What is the final volume fraction of syrup?

← Back to Homogeneous Mixture Practice Mode

Related Concepts

Pure Substance Solute Solvent Solution

Background Knowledge

These ideas may be useful before you work through the harder examples.

pure substance