1. TITLE

Hydrogen and Oxygen

2. DATE OF EXPERIMENT

Wednesday, November 19th 2014

3. EXPERIMENT DONE

Wednesday, November 19th 2014

4. PURPOSE

a) Knowing Hydrogen Gas Production Method

b) Knowing the nature - Hydrogen Gas Properties

c) Identifying Gas Hydrogen and its compounds

d) Mengethaui Oxygen Gas Production Method in the Laboratory

e) Knowing the existence of Oxygen Gas In A Compound

5. BASIC THEORY

I. HYDROGEN

Hydrogen (Latin: hydrogenium, from Greek: hydor: water, genes:

forming) is a chemical element in the periodic table that has the symbol H and

atomic number 1. At standard temperature and pressure, hydrogen is a

colorless, odorless, non- metal, single-valent, and is a diatomic gas that is

highly flammable. With the atomic mass 1.00794 amu, hydrogen is the lightest

element in the world.

Hydrogen gas is highly flammable and will burn at concentrations as

low as 4% H2 in air. The enthalpy of combustion for hydrogen is -286 kJ /

mol. Hydrogen burning according to the chemical equation:

2 H2(g) + O2(g) → 2 H2O(l) + 572  kJ (286 kJ/mol)

When mixed with oxygen in various proportions, hydrogen explodes

when ignited by the fire and will explode himself at a temperature of 560 ° C.

Result of burning flames of pure hydrogen-oxygen emit ultraviolet and barely

visible to the naked eye.

Hydrogen in the natural gas found in two forms, namely molecular

ortho and para hydrogen, both molecular forms differ in terms of the relative

spin of electrons and the nucleus. In ortohidrogen two proton spin is parallel to

form a state olekular called "triplet with spin quantum number 1 (1/2+1/2), on

the parahydrogen protonya spin antiparallel to form a state of" singlet "and its

spin quantum number 0 (1/2-1/2). At STP (Standard Temperature Pressure)

hydrogen gas composed of 25% and 75% form the ortho form. Bentu ortho

can not be purified, due to differences in the two forms of hydrogen are the

physical properties of the two are different.

Hydrogen has the atomic number and mass number 1,008. With atomic

number is the electron configuration 1s1 Hydrogen has and the number of

electrons in the shell 1. The hydrogen atom is placed at the top along with

class 1A, but keep in mind that hydrogen is not a member of class 1A and

hydrogen is not a member of any group in the periodic table. Hydrogen is

placed in the first period along with helium, and hydrogen are on the block of

the periodic system is the block s.

HISTORY

Hydrogen comes from the Greek hydro = water, and genesis =

formation. Hydrogen has been used for many years before finally expressed as

a unique element by Cavendish in 1776. Named hydrogen by Lavoisier,

hydrogen is the element that most of all the elements in the universe. Heavy

elements were originally formed from hydrogen atoms or of elements

originally made from hydrogen atoms.

RESOURCE

Hydrogen is expected to form a composition of more than 90% of the

atoms in the universe (equal to three quarters of the universe). This element is

found in the stars and play an important role in providing the energy source of

the universe through the proton-proton reaction and carbon-nitrogen cycle.

The process of fusion of hydrogen atoms into helium in the sun produces an

enormous amount of energy.

Hydrogen can be prepared in many ways:

• Steam from the heated carbon element

• Decomposition of hydrocarbons with some kind of heat energy

• Reactions of sodium or potassium hydroxide on aluminum

• Electrolysis of water

• Shifting acids by certain metals

In 1973, there were some Russian scientists who experimented produce

metallic hydrogen at a pressure of 2.8 MegaBar. At the transition point, its

density changed from 1:08 to 1.3 g / cm3. One year earlier in Livermore,

California, a group of scientists also reported a similar experiment in which

they observed the phenomenon occurs at the point of pressure-volume

churning on 2 MegaBar. Some predictions suggested that metallic hydrogen

may be metastable. Others predict hydrogen may be superconducting at room

temperature.

PHYSICAL AND CHEMICAL PROPERTIES OF HYDROGEN

Physical

Phase gas

Density(0 °C, 101.325 kPa)

0,08988 g/L

Melting point14,01 K

(−259,14 °C, −434,45 °F)

Boiling point20,28 K

(−252,87 °C, −423,17 °F)

T ripel point 13,8033 K, 7,042 kPa

The critical point 32,97 K, 1,293 MPa

Heat of fusion (H2) 0,117 kJ·mol −1

Heat of vaporization (H2) 0,904 kJ·mol −1

Heat capacity(25 °C) (H2)

28,836 J·mol−1·K−1

The vapor pressure

P/Pa 1 10 100 1 k 10 k 100 k

T/K 15 20

Atomic properties

The crystal structure hexagonal

The oxidation number1, −1

(oksida amfoter)

Electronegativity 2,20 (Scala Pauling)

The ionization energy 1st: 1312,0 kJ·mol −1

Atomic radius 25 pm

Atomic radius (calculation)

53 pm

Covalent radii 37 pm

The radius of the Van Der Waals

120 pm

Other Information

The thermal conductivity

(300 K) 180,5 m W·m−1·K−1

Speed of sound (gas, 27 °C) 1310 m/s

Hydrogen is very reactive and reacts with every oxidizing element of

nature and nature is more electronegative than hydrogen such as halide groups.

Hydrogen can react spontaneously with chlorine and fluorine at room

temperature to form hydrogen halide. Hydrogen can also form compounds

with less electronegative elements such metals to form hydrides.

Hydrogen solubility in organic solvents is very small when compared

to its solubility in water. Hydrogen can be absorbed in a metal such as steel.

The absorption of hydrogen by the steel causes the steel is brittle, causing

damage in the manufacture of the equipment. With these properties, the

scientists can store hydrogen in metals platinum ga.

At normal temperatures are in the form of hydrogen diatomiknya but at

a very high temperature hydrogen dissociates into atomic-ataomnya. Atomic

hydrogen is very reactive and can react with metal oxides such as silver,

copper, of lead, bismuth, and mercury to produce the free metal.

Atomic hydrogen can also react with organic compounds to form such

complexes with C2H4 to form C2H6 and C4H10. At very high pressure hydrogen

can have properties such as metal.

COMPOUND

Although hydrogen is gaseous, we very rarely found in the earth's

atmosphere. Hydrogen gas is very light, if not combined with other elements,

will collide with other elements and terkeluarkan of the layers of the

atmosphere. On earth hydrogen commonly found as a compound (water) in

which the atoms are linked by oxygen atoms. The hydrogen atoms can also be

found in plants, petroleum, charcoal, and others. As an independent element,

its concentration in the atmosphere is very small (1 ppm by volume). As the

lightest gas, hydrogen combines with other elements "sometimes explosively"

to form a variety of compounds.

a. HYDRIDE

The term hydride is used to indicate that the oxidation number

of hydrogen which reacts with other elements is -1 and is denoted as

H-. Some examples of hydride compounds are LiH, NaH, LiAlH4,

BeH2 and others. Bond in hydride compounds can be covalently to the

very nature of ionic and can be a part of this hydride molecules,

oligomers, polymers, ionic solids, the absorption layers chemical, or

even be part of a metal. Hydride reacts as a Lewis base and act as

reducing agents and can also be reacted with hydrogen radicals and

protons. Various elements to form hydrides and now become an

important subject of research to find a metal that can store hydrogen to

generate electricity or batteries. Hydride also plays an important role in

the synthesis of organic compounds due to nature as a reductant.

b. HYDROCARBONS

In the field of organic hydrocarbon compounds are defined as

compounds consisting essentially of hydrogen and carbon, but this

sense is widespread due to some hydrocarbons also contain other

elements such as phosphorus, nitrogen, sulfur and even metal

(organometallic). Very broad class of hydrocarbons including alkanes,

alkenes, alkynes, alcohols, esters, carboxylic acids, aldehydes, ketones,

amides, aromatic compounds and macromolecules such berbabagai

wide class of protein, and carbohydrates.

Generally, hydrocarbons are the main source of energy on earth

but with consideration of the current condition of the earth's energy use

began little by little transferred to an environmental friendly energy

sources. Hydrocarbons are also a source or base material to create a

wide range of organic compounds that others such as the petrochemical

industry is the basis for the manufacture of other chemical compounds.

c. HYDROGEN HALIDE

Hydrogen halide is a chemical compound that is produced from

the reaction of hydrogen with the element of group 7 for example

halide ie HF, HCl, HBr, and HI. HAT compounds rarely found in

nature and are not stable. Compounds of hydrogen halide (HX) is

acidic due to their tendency to release H + in solution. Unless HF

hydrogen halide then the other is a strong acid. In solution fellow

halide molecules can form hydrogen bonds in which the bond is

causing some compounds having boiling points higher than expected.

Tendency to react with the hydrogen halide is disebakan they have a

big enough difference kelektronegatifitas. The following comparison

of the size of the atom and the dipole moments of some hydrogen

halide.

d. H2O

Water molecule has two hydrogen atoms and one oxygen atom

covalently bonded. Oxygen binds strongly hydrogen due to the high

electronegativity of oxygen to produce positive and negative poles of

the water molecules so that it is donating water molecule has a dipole

moment. Fellow of water molecules can form hydrogen bonds thus

increasing the boiling point of water. Water may be in the description

as a molecule that has a polarity that can terdeprotonasi by the

reaction:

2 H2O (l)  H3O+ (aq) + OH (aq)The dissociation constants or Kw is 10-14 at 25 C.

ISOTOPES.

Normal hydrogen isotope called Protium. Other isotopes are

Deuterium (one proton and one neutron) and Tritium (one proton and two

neutrons). Hydrogen is the only element of the isotope-isotope has its own

name. Deuterium and Tritium are both used as fuel for nuclear fusion reactors.

One atom of Deuterium is found around 6000 atoms of hydrogen.

Deuterium is also used to slow neutrons. Tritium atoms are also

present but are fewer in number. Tritium can also be produced easily in

nuclear reactors and is used in the production of the hydrogen bomb (fusion).

Hydrogen gas is also used as a radioactive agent to create a bright luminous

paint.

Isotopes are elements with the same atomic number, but different

mass. These differences occur because different numbers of neutrons.

Hydrogen has three isotopes in nature, namely 1H, 2H, and 3H.

• 1H is a hydrogen isotope with an abundance of the most abundant where

abundance is 99.98%. Therefore, this isotope has one proton and one electron,

the other is the name protium.

• 2H, known by the name of Deuterium with essentially consists of one proton

and one neutron. Deuterium is not radioactive and harmless. This isotope is

used as a marker in the synthesis of organic compounds. Deuterium in the

form of 2H2O is often also used as a coolant in nuclear reactors and is also

used for the fusion reaction.

• 3H called Tritium containing two neutrons and one proton in its nucleus and

is radioactive and decays into helium-3 by emitting beta rays. Tritium is

widely used as tracers in the field as well as geochemical markers in chemistry

and biology experiments.

USEFULNESS

Hydrogen is widely used to fix nitrogen with other elements in the

Haber process (producing ammonia) and for the hydrogenation of fats and

oils. Hydrogen is also used in large quantities in methanol production, in

hydrogen dealkylation (hydrodealkylation), hydrocracking catalysts, and

hydrogen sulfurisasi. Other uses including as a rocket fuel, producing

hydrochloric acid, reducing iron ores and as a filler gas balloon.

Lifting capacity of 1 cubic foot of hydrogen gas at a temperature of

0.07 lbs 0 degrees Celsius and the air pressure 760 mm Hg. The battery-

fueled hydrogen (Hydrogen Fuel Cell) is a new technology that is being

developed, in which electric power can be generated in large quantities of

hydrogen gas. New plants can be built close to the sea for sea water

electrolysis process to produce hydrogen. This pollution-free gas can then

flow through the pipes and channeled into residential areas and major cities.

Hydrogen can replace natural gas, gasoline, agent in metallurgical processes

and chemical processes (refining), and turn trash into methane and ethylene.

Constraints that exist to realize the dream of many. Among public approval,

major capital investment and the price of hydrogen is still far more expensive

than other fuels now.

Some other uses of hydrogen:

In the investigation of weather and cosmic science, is used as a filler

material for mass air balloons light.

In the manufacture of ammonia (haber process)

N2 (g) + 3H2 (g) 2NH3

Preparation of nitric acid

Making of "petroleum"

In industrial margarine, fats and soaps pemasakn. The fat can be eaten

like margarine made from plant oils with hydrogen to do it together

under pressure and the presence of a nickel catalyst at 200 ° C.

Hydrogen required on fire blowing oxy - hydrogen to splicing or

melting metal

INDUSTRIAL SCALE

In industry, hydrogen can be made from hydrocarbons, from the

production of the biologically through the help of algae and bacteria, through

electrolysis, or thermolysis. Production of hydrogen from hydrocarbons still to

be excellent due to this method of hydrogen can be produced in large

quantities so that other methods need to be developed further enhance the

economic roots of hydrogen,

a. Making Hydrogen from Hydrocarbons

Hydrogen can be made from natural gas with an efficiency rate of

about 80% depending on the type of hydrocarbon used. Making

hydrogen from hydrocarbons produce CO2, so the CO2 is in the process

can be separated. Commercial production of hydrogen using the

"steam reforming" using methanol or natural gas and produce what is

referred to as syngas is a gas mixture of H2 and CO.

CH4  +  H2O       ->       3H2 + CO  + 191,7 kJ/mol

Heat required by the reaction of some sections obtained from the

combustion of methane. The addition of hydrogen results can be

obtained by adding water vapor into the reaction gases are flowed in

the reactor temperature of 130 C.

CO  + H2O       ->           CO2  + H2  – 40,4 kJ/mol

The reaction is taking oxygen from the water molecule to the CO to be

CO2. This reaction produces heat which can be used to keep the reactor

temperature.

b. Making hydrogen from water through electrolysis

Hydrogen can be made from the electrolysis of water using energy

supply diperbaharuhi eg angina, hydropower, or turbines. By

electrolysis, the production run will not produce pollution. The process

of electrolysis to be one process that has economic value urah

compared using hydrocarbon raw materials. One technique of

electrolysis that is high enough to get the attention of "electrolysis

using high pressure" in this electrolysis technique is executed to

generate hydrogen gas and oxygen with a pressure of about 120-200

bar. Another technique is to use the "high temperature electrolysis"

with this technique the energy consumption for the electrolysis process

is very low so that it can improve efficiency by up to 50%. Electrolysis

process using this method is usually combined with reactor

installations nulklir caused when using a heat source other then not be

able to cover the cost of the equipment is quite expensive.

c. Making hydrogen through biological processes

Some kinds of algae can produce hydrogen gas as a result of the

process of metabolism. Biological production can be done in a

bioreactor which supplied the needs of algae such as hydrocarbons and

the results of the reaction produces H2 and CO2 By using certain

methods of CO2 can be separated so that we just get alone H2 gas.

d. Decomposition of water with radio waves

By using radio waves, we can generate hydrogen from seawater to base

the decomposition process. If the water is exposed to polarized light

with a frequency of 13.56 MHz at room temperature, the seawater with

NaCl concentrations between 1-30% can be decomposed menjdi

hydrogen and oxygen.

e. Thermochemical

There are more than 352 thermochemical process that can be used for

splitting or thermolysis process in this way we do not require electric

current but the only source of heat. Some of this is a thermochemical

process CeO2/Ce2O3, Fe3O4/FeO, S-I, Ce-Cl, Fe,Cl and others.

Reaski terjdi in this process is: 2H2O -> 2H2 + O2 and all the

materials used can be recycled back to the process of new.

2. OXYGEN

Oxygen or acid is a chemical element in the periodic table that has the

system epitome O and atomic number 8. It is kalkogen group elements and can

easily react with almost all other elements (mainly into oxide). At standard

temperature and pressure, two atoms of the element bind to form dioxygen, are

compounds with the formula O2 diatomic gas that is colorless, tasteless, and

odorless.

HISTORY

For several centuries, the experts sometimes realize that air is composed of

more than one component. The behavior of oxygen and nitrogen as components

of air led to the development of the phlogiston theory of combustion, which

captured the minds of chemists for a century. Oxygen has been made by several

experts, including Bayen and Borch, but they do not know how to collect it. They

also do not study its properties and does not recognize as a basic element oxygen.

Priestley is credited with its discovery, although Scheele also discovered it

independently. In the past, the atomic weight of oxygen is used as a standard of

comparison for other elements, until in 1961, when the IUPAC (International

Union of Pure and Applied Chemistry) using carbon 12 as the new standard of

comparison.

RESOURCE

Oxygen is the third most elements are found in abundance in the sun, and play

a role in the carbon-nitrogen cycle, the process is thought to be a source of energy

in the sun and stars. Oxygen under excited conditions give a bright red color and

the yellow-green on the Aurora Borealis.

Oxygen is a gas, making up 21% by volume of the atmosphere and is obtained

by liquefaction and fractional distillation. The atmosphere of Mars contains about

0.15% oxygen. in the form of elements and compounds, the oxygen content of

49.2% by weight reaches the earth's crust. About two-thirds of the human body

and nine tenths of water is oxygen.

In the laboratory it can be prepared by electrolysis of water or by heating KCLO3

with MnO2 as a catalyst.

STRUCTURE

At standard temperature and pressure, oxygen is a colorless gaseous and

tasteless with the chemical formula O2, in which two oxygen atoms are

chemically bonded to elektrontriplet spin configuration. This bond has a bond

order of two and is often described simply as a double bond or as a combination

of the two-electron bond with two three-electron bonds.

Oxygen is a triplet ground state O2 molecules. The electron configuration of

the molecule has two unpaired electrons occupying two degenerate molecular

orbitals. Both of these orbitals are classified as antiikat (weakens the bond order

from three to two), so the diatomic oxygen bond is weaker than the nitrogen triple

bond.

In normal triplet form, O2 molecules are paramagnetic therefore magnetic

spinmomen unpaired electrons of the molecule and the negative exchange energy

between neighboring O2 molecules. Liquid oxygen will be attracted to the

magnet, so universally in laboratory experiments, liquid oxygen will form a

bridge between the two poles of a strong magnet. Singlet oxygen, the oxygen

molecule O2 is the name of the totality spin electron pairs. He was more reactive

to organic molecules in general. In nature, singlet oxygen is commonly produced

from the water during photosynthesis.

ALLOTROPES

Trioksigen (O3), known as ozone, an allotrope of oxygen that is highly

reactive and can damage lung tissue. Ozone is produced in the earth's atmosphere

when O2 joins with atomic oxygen resulting from the separation of O2 by

ultraviolet radiation (UV). Because ozone absorbs UV waves are very strong, the

ozone layer in the atmosphere serves as a radiation shield that protects the planet.

However, near the Earth's surface, ozone is an air pollutant formed from

automobile combustion byproducts.

Tetraoksigen metastable molecules (O4) was discovered in 2001, and assumed

to be contained in one of the six phases of solid oxygen. This was evidenced in

2006, by pressing the O2 up to 20 GPa, and found rombohedral O8 clump

structure. This clump potential as a stronger oxidant than O2 and O3, and can be

used in rocket fuel. Metallic phase of oxygen was discovered in 1990 when solid

oxygen is pressurized to above 96 GPa. Also found in 1998 that at very low

temperatures, this phase becomes superconducting.

THE PHYSICAL PROPERTIES

The color of liquid oxygen is blue like the sky blue color. This phenomenon is

not related; sky blue color is caused by the spread of Rayleigh. Oxygen is more

soluble in water than nitrogen. Air contains about one molecule of O2 for every

two molekul N2, compared with the atmospheric ratio of about 1: 4. The solubility

of oxygen in water depends on the temperature. At a temperature of 0 ° C, the

concentration of oxygen in water is 14.6 mg • L-1, when at a temperature of 20 ° C

the dissolved oxygen was 7.6 mg • L-1. At a temperature of 25 ° C and 1 atm air,

fresh water containing 6.04 milliliters (mL) of oxygen per liter, when the

seawater contains about 4.95 mL per liter. At temperatures of 5 ° C, the solubility

increases to 9.0 mL (50% more than 25 ° C) per liter of pure water and 7.2 mL

(45% more) per liter for sea water.

Oxygen condenses at 90.20 K (-182.95 ° C, -297.31 ° F), and freezes at 54.36

K (-218.79 ° C, -361.82 ° F). Both liquid oxygen and oxygen solid blue sky. This

is due to the absorption of the red color. Liquid oxygen with high purity levels are

usually obtained by distillation of liquid bertingkatudara; Liquid oxygen can also

be produced from the condensation of air, using liquid nitrogen with cooling.

Oxygen is a highly reactive substance and must be separated from materials that

burn easily.

ISOTOPE

Oxygen has nine isotopes. Natural oxygen is a mixture of three isotopes.

Oxygen atoms weighs 18 found in nature are stable and available for commercial

purposes, such as water (H2O containing 18 isotope by 15%). Commercial

oxygen consumption in the United States is estimated at 20 million tons per year

and is expected to continue to rise. The use of oxygen in steel furnaces is the

highest use. The amount also is required in the production of ammonia gas,

methanol, ethylene oxide and oxy-welding air asetilen.Pemisahan (distillation) to

produce gas with a purity of 99%, whereas only 1% electrolysis.

- Entered into porcelain cup

-Flush with disttilled water-Observed

-Checked with litmus paper

A few pieces of calcium

White powder

6. DESIGN OF EXPERIMENT

a) Material & Tools

Hydrogen

No Tools and Materials Amount1234567891011121314151617

Reaction tube side pipeMeasuring glassDishBunsenCa pieceMg PowderKI 0,05MH2O2 4.5 %Litmus paperWoodZn powderGlass cottonCottonPorkAquadesKClO3

KMnO4

121

1

1ml

21

1

Oxygen

No Tools and Materials Amount123456789101112

Reaction tube side pipeMeasuring glassPlastic pipePlastic closedStatif and clemBunsenKClO4

KIH2O2 4.5 %Litmus paperWoodKawi stone powder

121111

0.05 M

21

b) Procedure of ExperimentHydrogen experiment

1.

-Entered into porcelain cup containing distilled water

-Heated over a flame

-Checked by PP-Observed

Small spoon of magnesium powder gray

Pink solution

The powder does not dissolve

Slightly soluble water

-Entered into test tubes containing wet and dry cotton -Entered dry cotton-Close the test tube with a rubber cap-Heated

-Tested flame

0,02 gram of zinc powder

Gray powder

2.

3.

Some zinc metal

-Entered in tube side piped-Hose conected to a container measuring cup placed upside down in the water-Added 4M solution of hydrochloric acid sufficiently

-Closed with a rubber cover -Tested flame

Arise burst

The solution was gray, arise bubble

A few drops of solution H2O2 4,5%

-Entered into test tube-Added 1mL KI

-Added a little starch solution-Observed

Yellow solution

4.

5.

Potassium Chlorate

-Inserted into the test tube as high as ±0,5 cm from the bottom of the tube

-Added a little powder manganese

-Heated

-Collected gas by moving into water-Tested with sticks glow

Fire the greater

White powder

White powder and black

Black powder melts, gases arising

±0,5 gram of permanganate

-Entered in test tube an connected to the piped side container

-Added drops by drop 4,5% hydrogen peroxide (with caution)-The tube was closed with a rubber cover

-Left about 10 minutes for the gas to accumulate -Tested with sticks glow-Compare with the experimental gas volume 1

purple- black powcer

Oxygen experiment

1.

2.

7. DATA

8. ANALYSIS

9. DISCUSSION

10. CONCLUSION11. REFERENCES

Achmad, Hiskia. 2001. Kimia Unsur dan Radiokimia . Bandung  : PT. Citra Aditya Bakti.

Amaria. dkk. 2014. Penuntun Praktikum Kimia Anorganik II Unsur-Unsur Golongan

Utama. Surabaya. Unesa Press.

Anonim. 2014. Hidrogen. http://id.wikipedia.org/wiki/Hidrogen. accessed on 20

November 2014.

Anonim. 2013. Oksigen. http://id.wikipedia.org/wiki/Oksigen. accessed on 20 November

2014.

Vogel (1985). Buku Teks Analisis Anorganik Kualitatif Makro dan Semimakro, Jakarta :

PT. Kalman Media Pusaka

Soetrisno, Misawa. 2008. Oksigen. http://www.chem-is-try.org/tabel_periodik/oksigen/.

accessed on 20 November 2014.

Yulianto, Mohsin. 2004. Hidrogen. http://www.chem-is-try.org/tabel_periodik/hidrogen.

accessed on 20 November 2014.

.

ANSWER QUESTIONS

Hydrogen1. Explain what is explosion gas and its function!

Gas bubbling was caused due to the reaction of H2 gas with the flame, which is

basically the H2 gas is indeed very reactive to the fire because it reacts with the O2.

And at the laboratory scale blast is used to identify the presence of H2 gas.

2. Write all reaction on the experiment above!Experiment 1 : Ca(s) + 2H2O(l) Ca(OH)2(aq) + H2(g)

Experiment 2 : Mg(s) + 2H2O(l) Mg(OH)2(aq) + H2(g)

Experiment 3 : Zn(s) + 2H2O(l) Zn(OH)2(aq) + H2(g)

Experiment 4 : Zn(s) + 2HCl(aq) ZnCl2(aq) + H2(g)

Experiment 5 : 2KI(aq) + H2O2(aq) 2KOH(aq) + I2(aq) + H2(g)

3. Why hydrogen peroxide is used in dilute solution!Hydrogen peroxide is a liquid that is practically colorless. Is highly explosive and

dangerous in tinggi.Biasanya concentration of hydrogen peroxide is used as an

aqueous solution, but the 90% solution in water use.

Oxygen

1. Calculate the volume of oxygen gas is obtained when available KCLO3 1 gram !

Mol KClO3: 1/122,5 = 0,008mol

2KClO3 + MnO2 2KCl + 3O2 + MnO2

M: 0,008 - - - -R : 0,008 0,004 0,008 0,012 0,004S : - 0,004 0,008 0,012 0,004V O2 = 0,012 x 22,4

= 0,2688 L = 268,8 mL

2. Give the Lewis structure that indicates an O2 molecule with two unpaired valence

electrons!

3. Explain the events of experiments 1 and 2!

Experiment 1

In this experiment aims to find ways of making and identification of

oxygen gas. Potassium chlorate is grayed put the test tube to a height of

0.5 cm from the bottom of the tube and add three tablespoons of

manganese spatula then covered with a rubber stopper and a hose

connected to the measuring cup that has been filled with water and placed

upside down in the water. The test tube is heated, white smoke is visible

oxygen gas with a volume of more than 100 ml. heating process aims to

accelerate the reaction and manganese acts as a catalyst. For identification

of the tested gas flame with flame produced timber growing. It shows one

of the properties of oxygen gas that can enlarge the flame. The reaction

equation:

2KClO3(s) +2MnO2 (s)KCl(aq) + 4O2(g)+ 2KClO4(aq)

Experiment II

Subsequent experiments, a total of 0.05 g of permanganate put into a test

tube and add 5 drops of hydrogen peroxide 4.5%. Along with the mouth of

the tube was closed with a rubber stopper directly along the hose that is

connected to the measuring cup is placed upside down in the water. White

smoke formed an oxygen gas that drives the water in a measuring cup to

get out. But in this experiment the oxygen gas produced very little so that

the volume of gas that is obtained only 1 ml. same as the previous

experiment as a test identification of the gas flame with flame produced

timber growing. It shows one of the properties of oxygen gas that can

enlarge the flame. The reaction equation:

KMnO4(s) + 2H2O2 (aq) K+(aq) + Mn2-(aq) +3O2(aq) +3 H2O(l)

4. Write the equation in experiments 1 and 2!

Experiment 1 :2KClO3(s) +2MnO2 (s)KCl(aq) + 4O2(g)+ 2KClO4(aq)

Experiment 2 :KMnO4(s) + 2H2O2 (aq) K+(aq) + Mn2-(aq) +3O2(aq) +3 H2O(l)