Chemistry Flashcards
EQ1. What is matter?
Matter is anything that takes up space and has mass. All matter is made up of particles. EG. Water, rocks.
Non-matter doesn’t have mass, doesn’t occupy space EG. Energy (light, sound)
Mass = the amount of “material” in an object. It tells us how heavy something is without considering gravity. So, even if you’re on Earth, the Moon, or floating in space, the mass of an object stays the same. We measure mass in units like grams or kilograms.
Element = contains atoms with the same atomic number.
Compound = contains 2+ elements chemically joined together.
Mixture = 2+ elements/compounds, that are not chemically combined together and can be separated by physical processes.
EQ2. What is the particle model?
Matter is arranged as a solid, liquid and/or gas. Substances change state:
Solid = Rigid, fixed shape, fixed volume.
Liquid = Not rigid, no fixed shape, fixed volume, cannot be squashed.
Gas = Not rigid, no fixed, shape, no fixed volume, can be squashed.
I can distinguish between a solid, liquid and gas using a diagram as an example.
Particle model = a way scientists explain what things are made of and how they behave.
1. Everything is made up of tiny particles.
2. Particles are always moving – In solids, they’re packed tightly and only vibrate a little. In liquids, they’re a bit more spread out and can move around each other. In gases, they’re far apart and move very quickly in all directions.
3. The spaces between particles change – Solids have tiny spaces between particles, liquids have a bit more space, and gases have a lot of space between particles. This is why solids keep their shape, liquids can flow and take the shape of their container, and gases spread out to fill any space.
This model helps explain why ice melts, why water evaporates, and why we can smell things from far away!
EG3. What is a pure substance?
Pure substance = only 1 kind of particle in it. Either a single element, or compound, that is not mixed with any other substance. They will melt and boil at specific temperatures, so we can use the temperature that it melts/boils at to tell how pure it is.
Pure elements EG. oxygen, hydrogen, potassium.
Pure compounds EG. water, sodium chloride, carbon dioxide.
Mixture = 2+ elements/compounds, that are not chemically combined together, they are physically combined and can be separated by physical processes.
Homogenous mixture EG. salt water, mouthwash, alloys.
Heterogenous mixture EG. pizza, salad dressing, landfill.
Impure substance = Impure substances will melt/freeze or boil/condense over a range of temperatures.
EG. salt water, because it’s a mixture. You could separate them if you wanted (by boiling the water to leave the salt behind), but they’re still mixed up.
EQ4. What is a solution
Solvent = liquid, the substance doing the dissolving EG. water.
Solute = solid, the substance to be dissolved EG. sugar.
Solution = 2+ dissolved substances. They’re mixed together so well you only see 1 thing - it looks pure, but it’s not. It is the mixture formed when a substance dissolves in it. EG. sugar dissolved into water, salt dissolved into water.
Suspension = each substance keeps properties and can be separated to original form.
Dissolve = mixing of a substance in a liquid.
Soluble = a substance which can dissolve (mix in a liquid). EG. Salt, sugar.
Insoluble = a substance which cannot dissolve (mix in a liquid). EG. Flour.
Saturation = it happens when you’ve added so much solute (like sugar) to the solvent (like water) that it can’t dissolve anymore. At this point, any extra sugar you add will just settle at the bottom because the water is saturated – it’s full and can’t hold any more sugar.
EQ5. How do indigenous cultures separate mixtures?
- Hand Picking: This is a simple way to separate things by hand. For example, when gathering bush foods, Aboriginal people might pick out edible berries or seeds and remove any leaves or twigs by hand. It’s a quick way to choose only what’s useful or safe to eat.
- Sieving: Sieving involves using a tool with small holes (a sieve) to separate larger particles from smaller ones. Aboriginal and Torres Strait Islander peoples might use sieving when preparing flour from seeds or grains. They would use a woven mat or basket with holes just big enough to let fine flour pass through, leaving behind larger pieces that need more grinding.
- Cold Pressing: Cold pressing is a way to press or squeeze something without using heat. Aboriginal and Torres Strait Islander peoples might use cold pressing to extract oils from seeds, nuts, or other plants, like pressing seeds to get oils for food or medicine.
EQ6. What is filtration?
Filtration = a process used to separate solids from liquids or gases by using a filter. The filter catches the solid particles while allowing the liquid or gas to pass through.
EG. Water Filter: Used to make water clean by removing dirt, germs, and chemicals. You might see these in water bottles, fridges, or taps.
EG. Air Filter: Found in air conditioners, heaters, and even car engines. It cleans the air by catching dust and other tiny particles so we breathe in fresher air.
EG. Coffee Filter: Used to separate coffee grounds from water when making coffee, so you only get the liquid coffee in your cup.
EG. Sieve: A type of filter used in cooking to separate big pieces from small ones, like when you sift flour or strain pasta from water.
EG. Face Mask: Works as a filter to block dust, pollen, or germs from being breathed in, helping keep our lungs healthy.
Each filter has a different job, but they all help separate things we don’t want from things we do!
Filtrate = This is the liquid that passes through a filter. EG. when you make tea with a strainer, the tea liquid that goes through and into your cup is the filtrate.
Residue = This is what gets left behind on the filter. EG. tea leaves caught in the strainer are the residue.
So, filtrate is what goes through the filter, and residue is what gets left behind!
I can separate substances using the filtration process.
EQ7. What is decantation?
Decantation = a way to separate liquids from solids, or two liquids that don’t mix, by carefully pouring one off the top. EG. Water and Sand: If you have a cup with water and sand mixed together, the sand will settle to the bottom. By gently pouring the water out, you can separate it from the sand. EG. Oil and Water.
I can demonstrate how to decant liquids using lab equipment.
I can create an investigation using different liquids to compare decantation.
EQ8. What is evaporation?
Evaporation is a slow process involving the energy of the sun.
Evaporation = when a liquid turns into a gas. This usually happens when the liquid is heated or left out in warm air, and the particles in the liquid gain enough energy to spread out into the air as gas.
EG. Puddles Drying Up – After it rains, puddles of water slowly disappear as the water evaporates into the air, especially on a sunny day.
EG. Boiling Water – When you boil water on the stove, some of it turns into steam (a gas) and escapes into the air as evaporation happens.
EG. Wet Clothes Drying – When clothes are hung out to dry, water in the clothes evaporates into the air, leaving the clothes dry.
I can complete a process of evaporation using lab equipment
EQ9. What is distillation?
Distillation = the process to produce pure water. It involves boiling the solution and then condensing the vapour back into liquid by cooling it down.
Evaporation: process of evaporation.
I can label the equipment used for distillation in the laboratory
Distillate = pure water (distilled water).
EQ10. What is crystallisation?
Crystallisation = the process where a solid forms from a liquid as it cools or when the liquid loses its ability to hold onto the dissolved substance.
EG. Salt Crystals: If you dissolve salt in warm water and then let the water slowly evaporate, the salt will start to form into small crystals as the water disappears.
EG. Sugar Crystals: When you make rock candy, you dissolve sugar in hot water and then let it cool. Over time, the sugar crystallizes and forms large, hard sugar crystals on a stick.
Crystallisation happens when the liquid can’t hold all the dissolved particles anymore, and they come together to form solid crystals. It’s how things like salt and sugar can “grow” into crystals!
EQ11. What is chromatography?
Chromatography = a separation method for mixtures of substances with different colours. Chromatography helps scientists see and study the different parts of a mixture, like colours in ink or chemicals in plants.
EG. Ink on Paper: If you put a drop of black ink on a piece of filter paper and then dip the bottom of the paper into water, the water will slowly move up the paper. As it does, the different colours in the ink will separate, and you’ll see the ink spread out into different colour bands. This happens because the colors in the ink travel at different speeds through the paper.
EG. Separating Plant Pigments: If you crush some leaves and use chromatography, the pigments (like green chlorophyll) will separate into different colours, showing how plants have different pigments inside them.
I can use paper chromatography to separate substances in food colouring.
