Lesson video

Welcome to today's lesson on metal oxides and non-metal oxides.

This is part of the unit, acids and bases.

My name's Mrs. Mytum-Smithson, and today's lesson is about metal and non-metal oxides.

Maybe you know something about these or maybe not, but don't worry because we're going to work through this lesson step-by-step, and by the end of the lesson, you should be able to describe the properties of metal and non-metal oxides, and write equations to represent reactions of metal oxides with acid.

Here are the keywords for today's lesson.

Metal oxide, non-metal oxide, adding to excess.

On the next slide, there's some sentences that contain these keywords.

So pause that slide, and then when you're ready to start the lesson, press play.

Today's lesson consists of two learning cycles.

Firstly, we're going to do about metal oxides, and then we're going to take a look at non-metal oxides.

So first of all, let's get going with metal oxides.

A metal oxide consists of metal atoms bonded to oxygen atoms.

There are many metal oxides that exist.

So here's some calcium oxide.

This is a white powder.

We've got chromium oxide.

This is a greenish color.

Got iron oxide.

This is a reddish brown color.

You might have seen this, this is rust.

So these are some examples of many of the metal oxides that exist.

What I'd like you to do for this check for understanding is select all correct statements.

So the ones you've got to choose from are a metal oxide is where metal atoms are bonded to oxygen, a metal oxide is where a metal atom is mixed with oxygen, carbon dioxide is an example of a metal oxide, silver oxide is an example of metal oxide.

Pause the video for some thinking time, press play, and we'll go through the answers together.

Well done if you said a metal oxide is where metal atoms are bonded to oxygen, and silver oxide is an example of a metal oxide 'cause silver is a metal, and that is bonded to oxygen, making silver oxide.

So well done if you got both of those correct.

Metal oxides are bases, and this means that when they're dissolved in water, they will turn universal indicator a blue color because they will form an alkaline solution.

So let's watch a video to show this happening.

So what we're going to do in this experiment is firstly we're going to create a metal oxide.

So we're going to take some magnesium and react it with the oxygen in the air.

Just needs a little bit of heat from the Bunsen burner to get this going.

So we'll just warm it up until the reaction starts, and we'll take it out the Bunsen burner flame.

You can see this is a very bright white light, showing that the reaction's taking place, and you should be able to see the magnesium oxide forming.

So it's gone from being a silvery metal color to a white color.

So we're going to place the magnesium oxide that we just made there into that watch glass, sometimes called a clock glass because it's very big.

We're gonna then put some distilled water on there, and then some distilled water in the other watch glass.

Then what we're going to do is we're going to place some universal indicator, and we're gonna see what color it goes.

So here's some universal indicator solution going into the water there to see what color the solution of magnesium oxide and water makes.

So you can see it's a bluish kind of color, purple in places.

Just mix it up a little bit, and you can compare that to the neutral pH seven of the left-hand side watch glass.

So during that video, you should have seen that magnesium oxide was being formed when a reaction of magnesium and oxygen took place.

So that was that bright burning, and the white powder produced was magnesium oxide.

That magnesium oxide was then dissolved in water and tested with universal indicator, and that, because it turned a blue color, showed that that was an alkaline solution formed.

What color will universal indicator turn when a metal oxide is placed in water?

So here we've got three images, and we've got a piece of universal indicator placed in that metal oxide solution, and we've got them turning, A turns red, B turns green, C turns dark blue.

Pause the video while you choose one of those, and then press play, and we'll go through the answer together.

Well done if you said C, the universal indicator would turn dark blue because an alkaline solution has been produced when the metal oxide is dissolved in water.

Well done if you've got that one right.

Metal oxides are bases and can react with acids to neutralize them.

So if we take a look, if we've got a conical flask, and that's got some acid in it, you can see that the universal indicator paper is red, showing that.

We can then react the metal oxide with the acid to neutralize it.

And once it's neutral, we'll have a neutral salt solution, and that universal indicator paper will turn green.

So a neutral solution is green, and that shows pH seven.

The general equation for the reaction between a metal oxide and acid is metal oxide plus acid makes metal, salt, and water.

Here's a specific example.

So this time, we're using magnesium oxide plus hydrochloric acid, and that's going to make magnesium chloride and water.

The name of the salt produced during the neutralization reaction will depend on the type of acid used.

So here we've got a table summarizing this.

So if we use hydrochloric acid, the name of the metal salt ending will end in chloride.

So if we use sulfuric acid, we're going to make metal salts, and the ending for that will be sulfate.

And if we use nitric acid, the end of the name of the metal salt will be a nitrate.

So let's have a look at some examples.

So here we've got lead oxide plus hydrochloric acid makes lead chloride and water.

So you can see there that the hydrochloric acid has made lead chloride.

Then if we've got the same oxide, but this time we reacted with sulfuric acid, instead of making lead chloride, like we did with the hydrochloric acid, we're going to make lead sulfate and water.

And finally, lead oxide plus nitric acid makes lead nitrate and water.

So you can see there, we can make lead chloride, lead sulfate, or lead nitrate, and we can change those depending on that name of the acid that we use.

What I'd like you to do now is name the acid used when zinc oxide reacted to make zinc sulfate.

So was it hydrochloric acid, sulfuric acid, sulfate acid, or nitric acid?

Pause the video, select one of those, then press play, and I'll tell you if you're right or not.

So well done if you said that the name of the acid used was sulfuric acid, so sulfuric acid, when it reacts with zinc oxide, would make zinc sulfate and water.

So well done if you got that one correct.

What type of reaction takes place between metal oxides and acids?

Is it an oxidation reaction, an acidification reaction, or is it a neutralization reaction?

Pause the video, pick one of those, press play, and I'll tell you if you're right.

Well done if you said neutralization.

So because metal oxides are bases, you can then neutralize an acid by using a metal oxide.

So it would be a neutralization reaction.

Well done if got that one correct.

So what we're going to do now is we're going to carry out an experiment, and there's three parts to this experiment.

Firstly, we're gonna neutralize the acid, and we're going to use sulfuric acid with a metal oxide base, and we're going to use copper oxide.

So the first part of the experiment is neutralizing the acid.

The second part, we're going to carry out filtration.

So we're going to filter to remove the excess insoluble base.

So we're going to filter out copper oxide from the reaction mixture, and finally, we're going to crystallize this copper sulfate product.

So that'll be the final part of the experiment.

So three parts, neutralizing the acid, filtering it to remove the excess, so that's, so excess means too much, so the excess, the extra insoluble base that we'll have added, and then crystallizing the copper sulfate product.

So crystallizing that metal salt formed.

The first step we're going to do is we're going to neutralize the acid with a metal oxide base.

So we're going to gently warm the sulfuric acid just until you start to see bubbles forming at the bottom of the beaker, and then turn off the heat.

You're going to add one spatula of copper oxide and give it a stir with a stirring rod, and you're going to stir it until the fizzing stops.

So you should see bubbling or fizzing.

And when that stops, and you cannot see any more black copper oxide, you're then going to add another spatula of copper oxide to that solution of sulfuric acid.

And you should start to see the color of your solution change as the copper sulfate's formed.

So you're going to repeat that again.

You're going to stir until the fizzing stops, and you cannot see the copper oxide.

Then you're going to repeat steps four and five, so you're gonna continue adding a spatulaful at a time until no more bubbles are seen, and the black copper oxide remains.

And this means that you've added enough copper oxide for the reaction to take place, and a little bit more, so the copper oxide has been added in excess.

Here's a quick true or false.

When reacting copper oxide with sulfuric acid, all the copper oxide should be added at once.

Is that true, or is that false?

Pause the video while you decide, then press play for the answer.

Well done if you said false.

Now I want you to tell me why you said false.

So should it be added one spatula at a time until all the copper oxide has been added, or it should be added one spatula at a time until the copper oxide is in excess?

So pause the video, select one of those justifications, and then press play, and I'll go through the answer with you.

Well done if you said it should be added one spatula at a time until the copper oxide is in excess.

So once all the fizzing stopped, all the bubbling stopped, and you've got a little bit of copper oxide there at the bottom of your reaction mixture, and that means that the copper oxide is in excess.

Well done if you got that correct.

Here's step two of your reaction that you're going to carry out today.

So now what we're going to do is we've got excess copper oxide at the bottom of that copper sulfate solution, and we want to filter that out.

So we're going to use a filtration setup here.

So we've got a conical flask with a funnel and some filter paper in the top.

You're going to pour in your copper sulfate solution with that excess copper oxide in, and that should then filter, you should remove all the excess copper oxide.

You're going to dispose of the excess copper oxide safely.

So you're going to listen to your teacher, and they will tell you how to do that safely.

And then you're going to make sure that you keep the right thing.

So you need to keep the copper sulfate solution that's in the conical flask for the next stage.

After filtration, what should you keep for the next part of the experiment?

So in the diagram, I've circled three different parts of the diagram, so three different parts.

What I want you to tell me is what are you going to keep for the next part of the experiment?

Pause the video while you decide, and press play, and let's go through the answer together.

Well done if you said C, you're going to keep that copper sulfate solution.

We should have got rid of the impurities of the unreacted copper oxide that was placed in that reaction mixture in excess.

So you should now have a nice, turquoisey blue, clear, so no little particles in there, solution.

Well done if you got that one right.

Now let's look at step three.

So here what we need to do is we need to evaporate the water from the copper sulfate solution, and we should form some nice copper sulfate crystals.

So you're going to pour the copper sulfate solution into an evaporating basin.

Now this second part, this is going to take some patience.

You're going to place a copper sulfate solution in a warm room, and you're going to leave it until the water evaporates, and this might take a few days.

So then we've got 24 hours plus, so it's not gonna happen immediately.

You're going to place it somewhere safe, and your copper sulfate crystals should form in the evaporating basin.

Here's some that I made, and you can see that there's still a little bit of copper sulfate solution there, so we just need to wait maybe another day for that water to evaporate and leave us with copper sulfate crystals.

What I'd like you to do now is name the process used to obtain copper sulfate crystals from copper sulfate solution.

Is it filtration, evaporation, or neutralization?

So pause the video while you decide, and then press play, and I'll tell you the answer.

So well done if you said evaporation.

So evaporation is used to obtain the copper sulfate crystals from copper sulfate solution.

You just let the water evaporate off, and left behind will be those nice copper sulfate crystals.

What I'd like you to do now is carry out the practical to make copper sulfate crystals from copper oxide and sulfuric acid.

Then what I want you to do is write the word equation for the reaction of copper oxide and sulfuric acid to make copper sulfate and water.

So pause the video while you do that, and then press play, and we'll see how you got on.

Your results might look something to these.

So here's a class that I taught, and these are the copper sulfate crystals that they made.

See, nice turquoisey blue, nice big crystals because they've been evaporated over a long period of time.

Hopefully yours looks something like these.

And the word equation is copper oxide plus sulfuric acid makes copper sulfate plus water.

So well done if you got that correct.

For this part of the task, what I'd like you to do is complete the missing reactants and products, showing the reactions between metal oxides and acids.

So here's A, lead oxide plus hydrochloric acid makes something chloride plus water, lead oxide plus sulfuric acid makes lead something plus water, zinc oxide plus something acid makes zinc chloride plus something, something oxide plus something acid makes zinc nitrate and water, and finally, silver something plus nitric acid makes something nitrate plus water.

Pause the video while you complete that task, then press play, and we'll go through the answers together.

Well done for completing that task.

Let's see how you got on.

Lead oxide plus hydrochloric acid makes lead chloride plus water.

So the metal salt name comes from the metal oxide name and also the acid that was used.

So the hydrochloric acid makes chlorides, and we used lead oxide as the metal oxide, so that makes lead chloride and water.

Next one, we've got lead oxide again.

This time, we're reacting with sulfuric acid.

So sulfuric acid makes sulfates.

So we've got lead sulfate and water.

Zinc oxide plus something acid makes zinc chloride plus something else.

So we're going to have a look.

We've got a chloride made, so that means that we must have had hydrochloric acid, and we always make water, so water is the other product there.

And then we have a look at D, so for this one, we need to look at the products made.

So zinc nitrate must be made from zinc oxide, and also, because it's a nitrate, we must have used nitric acid.

Nitric acid makes nitrate salts plus water.

And then we've got silver something plus nitric acid makes something nitrate plus water.

So silver oxide, because remember, these are metal oxides, plus nitric acid is going to make silver nitrate plus water.

Well done for completing all of those.

I'm sure you've worked really hard and got them right.

Now we're going to move on to our second learning cycle, non-metal oxides.

A non-metal oxide consists of non-metal atoms bonded to oxygen atoms, for example, carbon dioxide.

Because carbon is a non-metal, when it's bonded to oxygen, it becomes an oxide.

So that's carbon dioxide is a non-metal oxide.

So carbon dioxide is used in fire extinguishers, and also, organisms in lakes can be affected by acid rain, and that's caused by pollution from sulfur dioxide.

So sulfur dioxide is another non-metal oxide because sulfur is a non-metal.

A quick check for understanding.

A non-metal oxide is, is it a metal atom bonded to oxygen atoms, non-metal atoms bonded to oxygen atoms, non-metal atoms bonded to nitrogen atoms, non-metal atoms bonded to metal atoms?

What I want you to do now is pause the video while you have a bit of a think, then press play, and I'll tell you the answer.

Well done if you said a non-metal oxide is non-metal atoms bonded to oxygen atoms.

Non-metal oxides in water make acidic solutions.

So here's our non-metal in water, and you can see we've got our universal indicator paper in, and it's turned red.

And red shows that that is an acidic solution.

Which could contain a non-metal oxide in water?

We've put the universal indicator paper in, and A has turned red, B has turned dark blue, and C has turned green.

Pause the video while you decide which one it is, then press play, and I'll tell you if you're right.

Well done if you said red.

Indeed, a non-metal oxide in water will make an acidic solution.

So that will turn universal indicator paper red.

Well done if you got that correct.

Now you're going to carry out a little bit of an experiment here.

So you're going to use universal indicator to test the pH of three non-metal oxides that have been placed in water.

So here's what you'll be using, nitrogen oxide in water, phosphorus oxide in water, sulfur dioxide in water, and you're going to complete the results table.

So we've got a results table here with the name of the non-metal oxide in water, so nitrogen oxide, phosphorus oxide, sulfur dioxide.

And then we've got space for you to write the color of the universal indicator solution or paper, depends on what's given to you.

And then you're going to say, is that acidic, is it neutral, or is it alkaline?

So you're gonna say acid, neutral, or alkaline.

And you're going to write a conclusion about the pH of the non-metal oxides in water, using results from your experiment.

And you may use this sentence starter below.

So it says some, all, or none of the non-metal oxides in water turned universal indicator, and you're gonna say what color it turned them or colors it turned them, and you're going to give me a reason for that.

So you're gonna write because and then complete that reason.

So pause video while you carry out that little experiment and those tasks, and then press play, and we'll go through the answers together.

So well done for completing that experiment.

So your results may look similar to this.

So color of the universal indicator, the nitrogen oxide is going to make it either red or orange, and that means it's acidic, so it's an acid.

Phosphorus oxide, again, it's going to turn red or orange, and that's also going to be an acid.

Sulfur dioxide is going to turn it red or orange, and that's also going to be an acid.

And then you're going to write this conclusion, so all of the non-metal oxides in water turned universal indicator red or orange because they're all acidic.

So well done if you got all of that correct.

Here's a summary for today's lesson about metal oxides and non-metal oxides.

A metal oxide consists of metal atoms bonded to oxygen atoms.

Metal oxides are bases and can react with acids to neutralize them.

Metal oxide plus acid makes metal, salt, and water.

A non-metal oxide consists of non-metal atoms bonded to oxygen atoms.

And non-metal oxides in water make acidic solutions.

Well done for working really hard during this lesson.

I hope you're feeling more confident now about metal oxides and non-metal oxides.

I hope you enjoyed making copper sulfate crystals and testing those non-metal oxides to see if they were acidic or not.

So well done for working really hard this lesson.

And I hope to see you again sometime soon.