CHEMISTRY FINAL TOUCHES 1

[00:00:01]Welcome.

[00:00:03]This video we look at the question which reads as follows.

[00:00:07]State the percentage of nitrogen gas in clean dry air.

[00:00:12]Such as 78%.

[00:00:14]All right, it's 78%. You need to know that one by heart. All right.

[00:00:19]State the bonding in a molecule of nitrogen gas. Remember that the nitrogen gas is is a type of bonding.

[00:00:28]Because nitrogen and another nitrogen they are both nonmetals, so the bond the bonding between nonmetals is known as covalent bonding.

[00:00:39]Or molecular bonding.

[00:00:44]Both are fine.

[00:00:47]They are just the the same.

[00:00:50]Nitrogen reacts with calcium to form calcium nitride.

[00:00:57]Okay.

[00:00:58]So, Mhm.

[00:01:01]What's the question?

[00:01:03]Calculate the relative molecular mass of calcium nitride.

[00:01:09]The relative Okay, all right, it's fine.

[00:01:13]Okay.

[00:01:15]So, calcium So, how many calciums are here? There are three.

[00:01:26]What's the mass number of calcium? 40.

[00:01:30]How many nitrogen are there? Two.

[00:01:32]Mass number there. So, we get 120 here plus 28.

[00:01:40]This should give you 148.

[00:01:43]Now, this is relative molecular mass. It does not have units.

[00:01:47]All right.

[00:01:50]Calcium nitride melts at 1,195°C.

[00:01:59]Deduce the of bonding in calcium nitrate.

[00:02:03]Remember, calcium is a metal.

[00:02:08]The nitride is coming from nitrogen.

[00:02:12]Okay, and is a nonmetal.

[00:02:15]So, the bonding between a metal and nonmetal is what we call ionic bonding.

[00:02:22]If you can't If you can't remember ionic, you can remember electrovalent bonding.

[00:02:33]So, this bonding involves the transfer of electrons, right? From a metal to a nonmetal.

[00:02:41]Deduce the separation and motion of the particles in melted calcium nitrate. So, when you talk about the separation, we're talking about how the particles arranged.

[00:02:50]All right? In melted, when something is melted, it turns into some form of a liquid or some form of aqueous solution or molten.

[00:03:01]So, because of that, we just say the the the particles are touching.

[00:03:07]All right? Touching particles.

[00:03:10]So, touching particles also sliding. Sorry.

[00:03:16]Um The particles are touching, yes.

[00:03:25]And they are also close to each other.

[00:03:29]Close to each other does not mean they are closely packed. It's a difference.

[00:03:32]All right?

[00:03:37]Motion.

[00:03:39]The particles are moving what? In a random motion.

[00:03:47]In a random motion.

[00:03:51]You can also say the particles slide over each slide over each other.

[00:04:03]For example, in a liquid form, the particles they overlap one another. They slide over each other. And