Grade 6 Science: Matter and Its Properties

Step 1: In the ice (a solid), water particles are packed in a pattern and only vibrate. The ice keeps its own shape and volume.

Step 2: Heat adds energy, so the particles move faster. When they slide past each other, the ice has melted into a liquid that takes the shape of the cup but keeps its volume.

Step 3: More heat makes the particles move faster still. They break away into a gas, which spreads out to fill any container.

Step 1: Gold is made of only one kind of atom, so it is an element, a pure substance.

Step 2: Water is two hydrogen atoms joined to one oxygen atom, always in that recipe. It is a compound, also a pure substance.

Step 3: Salt water looks the same all the way through, but it is salt dissolved in water. It is a solution, a homogeneous mixture.

Step 4: In a salad you can see the lettuce, tomato and cucumber. It is a heterogeneous mixture.

Step 1: Magnetism: drag a magnet through. The iron filings stick to it, and nothing else does.

Step 2: Particle size: pour the rest through a filter. Water and the dissolved salt pass through; the sand stays in the filter.

Step 3: Boiling point: heat the salt water. The water evaporates at a low temperature, and the salt is left in the dish.

Step 1: Shiny (has luster): a metal trait.

Step 2: Bends and can be hammered flat (malleable): a metal trait.

Step 3: A good conductor of electricity: a metal trait.

Step 4: All three point the same way, so it is a metal, from the left side of the staircase.

Step 1: The rare Earth elements are 17 silvery metals: the row shown below the main periodic table, plus scandium and yttrium.

Step 2: One of them, neodymium, makes the strongest permanent magnets we know. Tiny ones run phone speakers, earbuds and vibration motors; big ones run electric car motors and wind turbines.

Step 3: Others, like europium and terbium, glow in bright colors, so they help make the colors on screens.

Step 4: They are not actually that rare in the ground, but they are spread thin and hard to separate from each other, which makes them valuable.

Step 1: Water has a density of 1.0 grams per milliliter. The bead is less dense than water, so it floats in water.

Step 2: Cooking oil has a density of about 0.9 grams per milliliter. The bead is denser than oil, so it sinks in oil.

Step 3: In a glass with oil on top of water, the bead sinks through the oil and stops on top of the water.

Step 1: Bubbles fizz up right away, but nothing is being heated, so this is a gas forming: carbon dioxide.

Step 2: A thermometer in the cup drops a few degrees on its own: a change in thermal energy.

Step 3: Two pieces of evidence point the same way: a new substance formed, so this is likely a chemical change.