Notes on Separating Mixtures

Chromatography is good for separating dissolved substance made of diverse colours, like inks and plant dyes. This works because some dissolve in the liquid, which you can then put a piece of paper in and watch the magic.

Filtration is another good way to separate a insoluble solid from a liquid.

Evaporation is another good way to separate solutions. You evaporate one substance at it’s boiling point and the other will stay a solid or liquid, so you have separated it.

Simple distillation also works. You first evaporate one substance, then cool it back down in another container.

Fractional distillation is good for separating 2 or more liquids from each other. It’s distillation but with a few extra steps, like an extra filter of what’s-nots.

Separating Solutions

Lab # 2 Questions:

1. The substance that remain stick to each other, and stick to the walls of the cup.

2. It has evaporated

3. I think it’s salt because the teacher told us it was a salt water solutin

4.Taste it 😆 , or get a electron microscope and see if it is made of the same substances as salt.

 

Activity 4:

1.It would be heterogeneous because the cereal doesn’t dissolve into the milk.

2. I would get the solution with a syringe or something of the same build and get the solution from the ground. Then I would go into a lab and distill the solution so only the solution is left and everything else is left.

3. She created a solution, or a homogeneous solution. This is because it dissolved together and is inseparable, so it’s a solution, which is homogeneous. One substance dissolved another substance, which transformed it into a solution from a mixture.

Solubility Questions

Review

What is solubility?

Solubility is the amount of solute that can dissolve in a certain solvent at a certain temperature.
For a given solute and solvent, what factors affect solubility?
Temperature affects them, pressure affects gasses, and volume also matters.
You open a can of room temperature soda and pour it into a glass. Why does the soda go flat? Will it go flat faster or slower if you add ice? Why?
If you add ice it will go flat faster because the carbon dioxide can dissolve faster ad more of it can dissolve if it’s colder than if it was warmer.

States of Matter Focus questions

1. 500 grams of sand can be poured from one container to another container. The sand will take the shape of the container into which it is poured. Your friend says that the sand must be a liquid because it can be poured. How do you convince your friend that sand is a solid?

Just because sand is a solid doesn’t necessarily mean it’s one single solid object. Sand is actually a lot of sand particles, everyone sees as tiny spheres, in one area at a time. Sand couldn’t be a colloid that is part solid and liquid because you cant actually break apart the sand particles. You just separate the mixture of sand into 2 different mixtures.

2. According to the definition for matter, all matter has mass and volume. How would you prove that a gas, such as air, has mass and volume?

To prove volume, it’s actually quite simple, because gas takes up a lot of room. But to prove it, I could get dry ice and just have the dry ice melt(boil?) into gas. We can see the white dry ice gas particles, so we know it has volume. For mass, it’s a little bit harder. Actually, it’s quite simple think about it. To get density, we need mass and volume. Get a cup of water, and notice. Gas has a lower density than any liquid, so the gas won’t just flow into the cup and make the water spill out. But for gas to have a density, it needs to have a mass and a volume.