00:00 Good day everyone, my name is Mr. Ife and I am your basic science instructor.

00:22 Our lesson for today is oxygen and hydrogen gas.

00:31 A quick run prove to the objectives.

00:35 At the end of the class, students will be able to write a method of preparing oxygen,

00:40 hydrogen and carbon dioxide in their laboratory.

00:46 Students will be able to write the properties of oxygen and hydrogen.

00:50 And also, the test of oxygen and hydrogen.

00:56 Students should be able to use oxygen and hydrogen and also the preparation of the gases.

01:09 Oxygen is a gas and it is an in-natural state, it is colorless, it is odorless.

01:20 Oxygen is that air that is which you breathe in.

01:26 Oxygen is a colorless, odorless, tasteless gas, which is essential to every living organism.

01:36 As long as you are living, you need oxygen to breathe.

01:42 This oxygen is being taken up by animals which then converts it to carbon dioxide.

01:50 Since animals will breathe in oxygen and will breathe out carbon dioxide.

01:57 The carbon dioxide that will breathe out, the plants take it in as what they absorb.

02:04 They utilize the carbon dioxide as a source of carbon and return the oxygen to the atmosphere.

02:12 So the plants will take in carbon dioxide and return the oxygen into the atmosphere.

02:23 Oxygen forms compounds by reacting with practically any other element.

02:32 So oxygen can be had with hydrogen and it is going to give you water.

02:38 So oxygen can react with any element.

02:43 So oxygen in its normal state from the picture, you can see it has eight electrons prevailing

02:49 around it.

02:58 It is handy to know the fresh 20 elements of the periodic table.

03:04 One 99% of the mass of the human body is made up of six of these elements.

03:10 Now the fresh 20 elements are also a good overview of the different element groups.

03:17 They also occur in more everyday chemical reactions.

03:22 The elements are listed in order of increasing atomic number.

03:26 You will be discussing, you will see the fresh 20 elements and the way they have been arranged

03:35 is in terms of the increasing of the atomic number.

03:40 The atomic number is the number of protons in atoms of each element.

03:50 In the order of increasing atomic number, the fresh 20 elements and their symbols are

03:55 hydrogen, oxygen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine,

04:08 neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium,

04:19 and calcium.

04:21 These are the first 20 elements.

04:29 Now let's go through to the physical property of oxygen.

04:34 Oxygen is a gas, so what are the physical properties of oxygen gas?

04:40 Oxygen exists in all three forms.

04:44 Oxygen exists as a liquid, it exists as a solid, and also as a gas.

04:51 The liquid and the solid forms are pale blue color.

04:57 In the liquid and the solid form, you get a pale blue color for oxygen.

05:04 However, oxygen gas is colorless like we have stated before, in its natural state, odorless

05:11 and tasteless.

05:13 Oxygen changes from gas to a liquid at the temperature of 182.96 degrees Celsius.

05:20 And then, it can be solidified or frozen at the temperature of -218.4 degrees Celsius.

05:34 Now to the chemical properties of oxygen.

05:39 Oxygen is a highly reactive element.

05:41 It can react and highly pragmatic, and is easily capable of combining with other elements.

05:53 Oxygen can combine with hydrogen, it can combine with lead, can combine with almost any element.

06:00 One of oxygen's most important chemical properties is that it supports combustion.

06:08 In the sense that it supports burning when you burn the bush.

06:13 Once it exposes, once the bush burning is exposed to oxygen, it begins to burn the more.

06:28 Oxygen also combines with elements at room temperature, for example, the formation of rust.

06:36 And water falls on iron, and it's exposed to oxygen.

06:42 That iron begins to undergo chemical reaction, and it is called roasting.

06:48 Decay is an example of oxygen and reacting with compounds.

06:56 Come on the outside and water are the main product of decay.

07:05 Now, the uses of oxygen.

07:09 What is oxygen used for?

07:11 Number one, it is used in oxyhydrogen and oxyacetylene, which are used for coating and welding.

07:20 If you have seen the welders, when they begin to weld, the fire that comes out is as a result

07:29 of this.

07:31 It is used in the large-scale production of sintences gases.

07:37 It is also used for artificial respiration in oxpitu.

07:41 And get to the oxpitu, the pressure cannot breathe properly, bringing oxygen, and its

07:47 aids respiration.

07:52 Method of preparing oxygen.

07:56 To make oxygen, hydrogen peroxide is poured into a conical

08:00 flask, containing some magnesium for oxide.

08:05 The gas produced is collected in an upside-down gas jar filled with water.

08:11 In our next slide, you will see a picture of this.

08:16 Our oxygen is being collected.

08:20 As the oxygen collects in the top of the gas jar, it pushes the water out, and oxygen

08:26 is being emitted.

08:30 This is a picture of how oxygen is being prepared, preparation on the testing for oxygen.

08:43 Now, oxygen gas, how do you prepare oxygen?

08:52 You can prepare oxygen by decomposing of hydrogen peroxide.

08:57 When you have hydrogen peroxide, if you want to decompose it, breaking it into two is

09:06 a chemical process, but decomposing it will give you water and oxygen.

09:17 From here, when you decompose, you will be left with water and oxygen.

09:29 So as a result of that, you already have your oxygen.

09:34 Now another process for preparing oxygen is a tamarge composition of some metallic oxide.

09:42 Now we have here lead oxide.

09:46 When you go through tamarge composition, it breaks into lead and oxygen.

09:55 Then your oxygen is being taken at this point and for tamarge composition of hydrogen peroxide,

10:03 because it includes water.

10:06 You will be having your water here.

10:10 Now the test of oxygen.

10:16 Oxygen ignites as a glowing splint and it supports combustion.

10:23 In the sense that when oxygen mixes with any form of fire, it begins to burn more and

10:34 more.

10:41 Hydrogen is denoted with H. It's also a colorless, odorless, tasteless and flammable geyser substance

10:49 that is in the simplest member of the family of chemical elements.

10:55 So hydrogen is also odorless, it is tasteless and it's a flammable geyser substance.

11:01 The earliest known importance chemical property of hydrogen is that it burns with oxygen to form

11:08 water.

11:10 When oxygen, when hydrogen, burns with oxygen, it forms water.

11:16 Indeed, the name hydrogen is derived from the Greek word meaning "maker" of water.

11:26 Now what's the physical property of hydrogen?

11:30 At standard temperature and pressure of hydrogen is a non-toxic, non-metallic, odorless,

11:36 tasteless, colorless and highly combustible, diatomic gas, with the molecular formula H2.

11:49 Hydrogen is also prevalent on eggs in the form of chemical compounds such as hydrocarbons

11:55 and water.

11:57 I've stayed there before.

11:59 Hydrogen in its normal states is odorless, tasteless and colorless.

12:07 Chemical properties of hydrogen, what are the chemical properties of hydrogen?

12:14 Hydrogen gas is highly flammable, that is, it can burn and will burn in air at a very wide

12:23 range of concentration between 4% to 75% by volume.

12:35 Hydrogen does form compounds with most elements, despite its stability.

12:43 Despite the stability of hydrogen, it will still form compounds with odor element.

12:49 When participating in reaction, hydrogen can have a partial positive charge when reacting

12:55 with more electronegative elements, such as the allogene or oxygen.

13:01 Oxygen in its normal state is not stable, it moves around, but hydrogen is stable but yet

13:07 when it comes across or mixes with any element, it becomes a compound.

13:13 Hydrogen gas can also explode in a mixture of chlorine.

13:21 The uses of hydrogen, what are hydrogen used for?

13:24 Number one, for refining petroleum, nearly all of the hydrogen consumed in the United

13:31 States is used by industry that refines petrol.

13:37 It is also used in treating metals, it is used in producing fertilizer, and also in processing

13:46 foods.

13:47 Number two, it is used in filling balloons and airship.

13:53 The airship needs hydrogen to be filled, so that it can float on air.

14:00 Number three, for adenine of animal oils and certain vegetable oils.

14:10 Number four, for rocket fuel is a major use of hydrogen for energy.

14:18 The rocket can fuel it with hydrogen and can be used to propel the rocket.

14:26 Hydrogen fuel sells produce electricity.

14:31 The hydrogen reacts with oxygen across an electrochemical cell, similar to that of a battery

14:37 to produce electric city, water and small amount of heat.

14:44 You can see in the picture the individual fuel cell can be used to generate electric power.

14:52 The oxygen comes in from this direction.

14:58 The hydrogen comes in from this direction and the oxygen comes in from that direction.

15:07 It can be used in vehicles.

15:10 The method of preparing hydrogen, it involves the action of hydrochloric acid on zinc granules.

15:18 When you have zinc granules, zinc particles, the action of hydrochloric acid on zinc granules

15:26 is as a result of hydrogen.

15:30 Adding the hydrochloric acid to zinc in a test tube funnel, hydrogen gas will be automatically

15:37 collected using delivery tube with a downward displacement of water.

15:48 hydrogen and testing for hydrogen.

15:52 Now, hydrogen.

16:00 You have hydrochloric, yet, and zinc.

16:09 Acid plus meta, hydrochloric is acid, then the zinc is meta.

16:16 This mix together, you get the salt and hydrogen gas, which becomes zinc chloride and hydrogen.

16:26 When this is decomposed, you get zinc chloride and you also get hydrogen.

16:34 And as a result, hydrogen is being stored in this place.

16:42 Let's go to the second one.

16:44 You have active meta plus water hydroxide plus hydrogen gas.

16:53 This is calcium plus water giving you calcium hydroxide and hydrogen.

17:08 Now, the test for hydrogen.

17:14 The pop-up test, when it leads tapah, when using a leads tapah, it will produce an audible

17:20 pop when placed in hydrogen glass, gas.

17:26 Gases can be produced in the school laboratory when a compound is heated and undergoes some

17:33 out the composition.

17:38 Electricity is used to decompose a compound, electrolytes the composition is called, electrolytes,

17:49 electrolytic decomposition.

17:53 Number three, a substance reacts with water or an acid in a displacement reaction.

18:02 In that way, gases can be produced in the school laboratory.

18:10 The fourth way to produce gas in the school laboratory is when it softens on the ghost

18:17 combustion in air.

18:18 Take for instance, you use a paper, you light it up with fire.

18:23 Some gas begin to emit and such, you have some gases.

18:29 So you can pick up those gases in a school laboratory, evaluation.

18:39 Write the method of preparing oxygen, hydrogen in the laboratory.

18:46 Number two, write down the properties of oxygen and hydrogen.

18:51 Number three, write the confirmatory test of oxygen.

18:57 Thank you for watching.

18:59 I am Miss Taipei, see you next time.