Grade 5 Science · NGSS 5-PS1 · Learning & practice

The Science of Baking: States of Matter

Sort the ingredients on a baker's bench, then trace what happens to matter when heat, mixing, and gases do their work.

Section 1 · Solids, Liquids, Gases

States of Matter on the Baker's Bench

By the end of this section I can describe solids, liquids, and gases using a particle model — so I can explain why flour, milk, and steam behave so differently.

Success criteria 0 / 3 ticked

Tick each one when you can do it without help.

1A A particle model for three states

Everything on the bench — flour, milk, the steam from the kettle — is made of particles too small to see. How those particles are arranged and how they move gives each substance its state.

The three states, in particles

SolidLiquidGas

Solid — particles are packed in a fixed pattern and only vibrate. The material keeps its own shape, like a sugar cube.

Liquid — particles are close but can slide past each other. It takes the shape of its container, like milk in a jug.

Gas — particles are far apart and move freely. It spreads to fill any container, like the steam above hot water.

Classify butter at 20 °C

Butter holds its shape in a dish. Particles are in a fixed arrangement → solid
Warm it to 40 °C and it pours. Particles now slide past each other → liquid
Heat it further and it vaporises. Particles spread freely → gas

Interactive · sort the ingredients by state at room temperature

Tap an ingredient, then tap the bin you think it belongs in. Tap "Check" when you've placed all six.

Solid 0

Liquid 0

Gas 0

Check yourself

A block of chocolate sits on a plate and keeps its own shape. Which state of matter is it in?

Think about whether the particles are locked in a fixed arrangement or free to slide.
A material that keeps its own shape has particles held in a fixed pattern, so it is a solid.

Steam rises from a kettle and spreads to fill the whole space above the water. Which state is the steam in?

Consider which state has particles far apart and moving freely to fill any container.
Particles that spread to fill a container are free and far apart, so steam is a gas.

Section 2 · Heating, Mixing, Reacting

Changes When We Bake

By the end of this section I can tell whether a baking change is reversible or produces new substances — so I can predict what happens to matter in an oven.

Success criteria 0 / 3 ticked

Tick each one when you can do it without help.

2A Reversible vs. irreversible changes

Some baking changes only swap the state — you can get the original back. Others make new substances that you cannot turn back, no matter what you do.

Two kinds of change

ReversibleIrreversible

Reversible — a change of state only. Melting butter and dissolving sugar in water are reversible: cool it or boil off the water and the original returns.

Irreversible — new substances form. Baking dough, toasting bread, and burning sugar create new materials (and often a smell and color change) that you cannot undo.

Toast a slice of bread

Bread enters the toaster pale and soft. Heat causes new substances to form → irreversible
The slice turns brown and smells different. A color change + new smell = a new substance
You cannot "un-toast" it. No cooling or filtering brings the pale bread back

What makes dough rise?

Yeast or baking soda releases a gas (carbon dioxide) inside the dough. The gas particles push outward and the dough expands. The gas is trapped in pockets, so the loaf keeps its risen shape once the protein network sets in the oven's heat.

Check yourself

You melt chocolate chips in a bowl, then let the bowl cool until the chocolate hardens again. Is this change reversible or irreversible?

Decide whether the chocolate returns to its original form after cooling.
Melting is only a change of state, and cooling brings the chocolate back to a solid — so the change is reversible.

A cake bakes in the oven: it browns, smells new, and cannot be turned back into batter. Is this change reversible or irreversible?

Look for signs that new substances have formed and cannot be undone.
Browning, a new smell, and an inability to recover the batter all show new substances formed, so the change is irreversible.

You weigh a sealed bag of bread dough before and after baking. The bag is closed the whole time. Is the total weight after baking greater, less, or the same as before?

Remember that matter is not created or destroyed, even when new substances form.
In a closed container the total weight of matter is conserved, so the weight is the same before and after.

This lesson took 60 seconds to make. Make one about YOUR kid's obsession, free.

Same Grade 5 Science outcomes, rebuilt around whatever your child is into this week - dinosaurs, Minecraft, horses, you name it.

Make your own lesson

This is a fixed example. Sprout writes a fresh, personalised lesson around your child every time - the example is the ad, the product is the personalisation.