← Back to course
Science Launch G5 / Week 03 / Friday
5/6
Week 03 · Mystery Materials

Friday

Properties at work
// Identify materials by their properties
⏱ about 15 min

Friday: Properties at work

Rocket and Raven visit a recycling center with Rocket's aunt. A belt carries a river of cans and bottles.

Above the belt, a big magnet hums. Steel cans jump up to it. Aluminum cans roll right underneath.

"It is my sorting machine, but huge!" Rocket says.

Raven watches closely. "It works because of one property," she says. "Which one?"

Nova blinks. "Great discovery," she says. "People use properties to sort things every day."

Sorting with properties

At many recycling centers, containers pass under overhead magnetic belts. The belts pull out steel and tin cans.

Aluminum cans are not magnetic, so they need another method to be separated.

This is the same property you tested on Tuesday, used on a giant scale.

ProblemProperty that helps
Separate steel cans from aluminum cansResponse to magnets
Tell salt from sugar without tastingSolubility
Identify a mineral in the fieldHardness
Pick a shiny material for a mirrorReflectivity
WHICH PROPERTY?
  • Read the question.
  • Tap your answer.
You need to pull steel cans out of a pile. Which property helps most?
You want to know if a mineral is softer than glass. Which test?
StatementTrue or false?
Magnets at recycling centers pull out aluminum cans.?
Solubility can help tell two white powders apart.?
Using more than one property makes an identification stronger.?
WHY THIS EXERCISEEach property answers a different question, and together they identify materials reliably.
Look around
Find two objects at home that look alike but are made of different materials.
Which property could tell them apart?

Two kinds of cans

A recycling center has a pile of mixed cans.

The magnet belt pulls out steel and tin cans.

Aluminum cans stay behind, so they are separated another way.

HOW MIXED CANS GET SORTED
  • ?Each kind is collected in its own place.
  • ?Cans ride along a moving belt.
  • ?Aluminum cans roll on underneath.
  • ?They pass under a big magnet.
  • ?Steel cans jump up to the magnet.
WHY THIS EXERCISEA magnet uses one property to sort steel from aluminum.
Overhead magnetic belts pull out ____ and tin cans.
To tell salt from sugar without tasting, test ____.
CHOOSE THE TEST
  • Read the question.
  • Tap your answer.
You want a shiny material for a mirror. Which property matters?
Why can't a magnet pull aluminum cans out?
Try it
With a grown-up, test a clean food can and a clean drink can with a magnet.
A grown-up checks for sharp edges first.
Which one is pulled? What might each be made of?
StatementTrue or false?
Steel cans are pulled by a magnet.?
A scratch test checks solubility.?
Each property answers a different question.?
WHY THIS EXERCISEDifferent tests check different properties.
Which property separates steel cans from aluminum cans? Type one word.
WHY THIS EXERCISESteel is magnetic and aluminum is not.

You connected lab tests to real jobs. Tomorrow is Launch Lab, a property hunt with your family.

← Thursday