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“We must trust to nothing but facts: These are presented to us by Nature, and cannot deceive. We ought, in every instance, to submit our reasoning to the test of experiment, and never to search for truth but by the natural road of experiment and observation.” ― Antoine Lavoisier, Elements of Chemistry

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The science of today is the technology of tomorrow, Edward Teller

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Success is no accident. It is hard work, perseverance, learning, studying, sacrifice and most of all, love of what you are doing or learning to do. Pele

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Optimism is the faith that leads to achievement. Nothing can be done without hope and confidence. Helen Keller

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Science without religion is lame, religion without science is blind. Albert Einstein

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Insanity: doing the same thing over and over again and expecting different results. Albert Einstein

Saturday, 30 November 2013

CHECKPOINT 2_ Chemistry : Rusting

IGCSE2 _Branched Alkane Alkene

click here to download

IGCSE2 - 1st SMT PHYSICS EXAM TRIAL

click here to download

AS LEVEL.....trial for 1st Semester Examination

Exam Trial for AS Level
Chemical Equilibrium.... check this out, click here to download

Wednesday, 13 November 2013

CP2 Experiment - Rusting of Iron

Dear CP2...
This is the material for Chem 2 Quiz next week.(November 20)
Click the link below to download
http://www.4shared.com/file/B2v48poc/Experiment-rusting-XX.html

Tuesday, 12 November 2013

Physics IGCSE (on chem 2 Nov 12)


Physics Task for IGCSE
Do this worksheet during Chem 2 session
Do with your group (1-3 persons). Submit it back to my email within this day. I will grade this task.
Click the link below to download

Wednesday, 9 October 2013

singe displacement reaction worksheet

complete this reactions. then convert into word equations
1.Ag + KNO3 →      
2. Zn + AgNO3 →      
3. Cl2 + KI →      
4. Cu + FeSO4 →      
5. Fe + Pb(NO3)2 →      
6. Cu + Al2(SO4)3 →      
7. Al + Pb(NO3)2        
8. Cl2 + NaI →      
9. Fe + AgC2H3O2      
10. Al + CuCl2 →        
11. Br2 + CaI2 →        
12. Fe + CuSO4 →        
13. Cl2 + MgI2 →        

Monday, 7 October 2013

IGCSE Sound worksheet

IGCSE2  Sound Worksheet
11.  State true or false for each of the following statement
a.       Sound travels the fastest in solids and slowest in air.
b.      Sound can travel in vacuum
c.       The speed of sound is    3 x 108 m/s
d.      The speed of sound is a constant.
e.      Sound can travel from the Sun to the Earth.
f.        Pitch means how loud a sound is.
22.  What is the meaning of compression and rarefaction in term of vibration of sound waves?
33.  Delia ties a silver spoon to a piece of string and holds the ends to her ears.

When her friend Donny, strikes the spoon with a pencil, Delia hears a sound like a bell.
Explain the reason for this.

44. Explain why we do not hear explosions on the Sun, although they must be very loud.
55.   A musical instrument produces a sound wave with a frequency of 1000 Hz.  The sound wave  has a wavelength of 0.34 m in air.  Calculate the speed of the sound wave in air.

66.  In water the speed of sound is different.  The speed of a sound wave in water is 1300 m/s. The sound wave has a frequency of 1000Hz.  Calculate the wavelength of this sound wave.

77.  The diagram shows a ship using an Echo locator (SONAR) to find a shoal of fish.  The pulsed wave is transmitted from the ship, which is then reflected off the top of the shoal and is then picked up by the receiver.

 

A ship sending sound signals to the sea receives the echo 2 s later. If sound travels a t 1400 m/s in sea water, how deep is the sea?


88.  A student sits in the middle of a rectangular hall is 17 m wide, as shown in the diagram below. When student bangsna drum, two echos are heared, 0.05 s and 0.08 s respectively, after the bang.





 Assuming that there is no echo from the ceiling, calculate:
(i)      The speed os sound in the air
(ii)    The length of the hall







Wednesday, 25 September 2013

Pattern of Reactivity Quiz

REACTIVITY SERIES - Chem is try  2
Workout these questions with your learning partner. There are 40 marks possibly.


1)      Answer the following questions in full sentences.
a)     Why does gold occur native (uncombined) whereas zinc does not?
………………………………………………………………………………………………
b)     Why was silver used to make coins in the past?
………………………………………………………………………………………………
c)      Why is copper used to make electrical cables and wires?
………………………………………………………………………………………………
 (3)
  2)      The following metals are listed in order of reactivity (most reactive first)
sodium  >  magnesium  >  zinc  >  copper
a)     Describe what each metal does when
(i)    heated in air  …………………………………………………………..
(ii)  added to dilute hydrochloric acid……………………………………..
b)     Which of the four metals would be suitable for making saucepans?  Explain why the others are not.
………………………………………………………………………………………………
………………………………………………………………………………………………
(5)

3)     Describe what you would see if you dropped a piece of magnesium ribbon into some copper sulphate solution in a test tube.  Write a word equation for the reaction.
………………………………………………………………………………………………
……………………………………………………………………………………………...
………………………………………………………………………………………………
………………………………………………………………………………………………
(3)

4)     Complete the following word equations.
a)     zinc   +   lead nitrate solution  ………………………………………………………….
b)     iron   +   zinc sulphate solution  ………………………………………………………..
c)      lead   +   copper nitrate solution ………………………………………………………
d)     magnesium   +   zinc chloride solution  ………………………………………………..
e)     copper   +   sodium chloride solution  …………………………………………………
f)       zinc   +   iron sulphate solution  ………………………………………………………..
g)     gold   +   silver nitrate solution  ………………………………………………………..
h)     magnesium   +  calcium nitrate solution  ……………………………………………..
(8)
5)     Three metals X, Y and Z have the following reactions:-
Y will displace X from a solution of its salt.
Z will displace both X and Y from solutions of their salts.
Place the three metals in order of reactivity, starting with the least reactive.
………………………………………………………………………………………………
(2)

6)     Here is a list of metals in order of decreasing reactivity.  Q and R are mystery metals.
K > Q > Ca > Mg > Al > Zn > R > Fe > Cu
a)     Will Q react with cold water?                                                              …………
b)     Will R react with cold water?                                                                              …………
c)      Will R react with dilute hydrochloric acid?                                 ...……….
d)     Will R displace copper from copper sulphate solution?    ...……….
e)     Write word equations for any reactions in parts a) to d)
………………………………………………………………………………………………….
………………………………………………………………………………………………….
………………………………………………………………………………………………….
………………………………………………………………………………………………….
(6)
7)     Describe everything you see when sodium is added to water containing universal indicator.

Name the two chemical products of sodium reacting with water and give the symbol equation for the reaction of sodium with water.
(3)
8)     (a) Give two observations that could be made after adding zinc to copper(II) sulphate solution.

(b) Give the symbol equation for the reaction between zinc and copper(II) sulphate solution.

(4)
(c) explain why this is an example of a displacement reaction.

  9   (a) Give three observations that could be made when magnesium reacts with sulphuric acid.
     (b) Give the word and symbol equation for zinc reacting with sulphuric acid.
     (c) From copper, iron, magnesium and zinc: Which reacts with acid (i) fastest?, (ii)slowest?
(6)


Tuesday, 24 September 2013

alkane alkene worksheet

WORKSHEETS
Worksheet 1 : Carbon Compound
1. Carbon compounds are compounds which contain ………………
2.Hydrocarbons are the simplest organic compounds containing …………….. and  …………….atoms  only. Some organic compounds  also contain other element such as oxygen, nitrogen and halogens ; the compounds are called ………………….
3.Saturated hydrocarbons contain entirely of carbon-carbon ……………….. bonds. Unsaturated hydrocarbons contain at least one carbon-carbon ……………… bond or carbon-carbon triple bonds.
4.The molecular formula is a chemical formula that shows the…………………………. of each element present in one molecule of the substance.
5.The structural formula  of an organic compound is the formula that shows  the ……………………………….. and the covalent bonds between atom in a molecule of the compound.
6.A ……………………series is a family of organic compounds with each member of the family differing from the previous member by having one more group of atoms
            –CH2 .  All members in the same family have the same  functional group and with
            similar …………………… properties.
7.A functional group is an atom or a group of atoms that determine the ……........ properties of an organic compound.
8 ……………………. are compounds which have the same molecular formula but
            different structural formula. The phenomenon whereby two or more molecules have the
            similar molecular formula but different structural formula is called ………………

As Level Chemistry-chemical equilibrium

Worksheet A            Equilibrium Calculations
            Solve each problem and show all of your work.
1.         SO3(g)         +     H2O(g)                ⇄    H2SO4(l)        
            At equilibrium [SO3] = 0.400M             [H2O] = 0.480M                  [H2SO4] = 0.600M            
            Calculate the value of the equilibrium constant.
 2.         At equilibrium at 100oC, a 2.0L flask contains:
            0.075 mol of PCl5             0.050 mol of H2O               0.750 mol 0f HCl           0.500 mol of POCl3
            Calculate the Keq for the reaction:
            PCl5 (s) + H2O (g) ⇄ 2HCl (g) + POCl3 (g)
3.         Keq= 798 at 25oC for the reaction:  2SO2 (g)   +  O2 (g) ⇄  2SO3 (g).
            In a particular mixture at equilibrium, [SO2]= 4.20 M and [SO3]=11.0M. Calculate the equilibrium [O2] in this mixture at 25oC.
4.         Consider the following equilibrium:
            2SO2 (g) + O2 (g) ⇄ 2SO3 (g)
            0.600 moles of SO2 and 0.600 moles of O2 are present in a 4.00 L flask at equilibrium at 100oC. If the Keq = 680, calculate the SO3 concentration at 100oC.
5.         Consider the following equilibrium:
            2 NO2(g)           ⇄        N2O4(g)
            2.00 moles of NO2 and1.60 moles of N2O4 are present in a 4.00 L flask at equilibrium at 20oC. Calculate the Keq at 20oC .
6.         2 SO3(g)           ⇄        2 SO2(g)           +          O2(g)
            4.00 moles of SO2 and 5.00 moles O2 are present in a 2.00 L container at 100oC and are at equilibrium. Calculate the equilibrium concentration    of SO3 and the number of moles SO3 present if the Keq = 1.47  x  10-3.
7.         If  at equilibrium [H2] = 0.200M and [I2] = 0.200M and Keq=55.6 at 250oC, calculate the equilibrium concentration of HI.
            H2 (g) + I2 (g) ⇄ 2HI (g)
8.         1.60 moles CO, 1.60 moles H2O, 4.00 moles CO2, 4.00moles H2 are found in a 8.00L container at 690oC at equilibrium.
            CO (g) + H2O (g) ⇄ CO2 (g) + H2 (g)
            Calculate the value of the equilibrium constant.

Wednesday, 18 September 2013

REACTIVITY SERIES worksheet

Workout these questions below.


Name                   : ______________________________              Marks   :
Date                      : ______________________________
 



1.    Katie and Nando have identical new bicycle. Katie lives in a dry, cool, grassland area and Nando lives in warm, wet region on the coast. Which bicycle may show signs of rusting first? Explain your answer.

2.    What is the relationship between rusting of metals and their reactivity?

3.    Iron, Aluminum, Lead, Copper, Tin, Zinc, Magnesium. Which of these element will rust first and which is the last?

Arrange the elements according to the reactivity. (most reactive to less reactive)

4.    Suggest the statement below:
a.         The roof of the house are potassium plate
b.         We can protect the fence in the yard by painting

Friday, 30 August 2013

Laboratory Techniques, Safety in The Laboratory worksheet


What Are They Doing Wrong??

List what are they doing wrong in the picture below.


Wednesday, 21 August 2013

Scientific Methods Worksheet


Scientific Method Worksheet
Name :
Class/# :
Day, date :

Step 1: Put the steps of the scientific method in the correct order.

Do background research
Ask a question
Analyze results
Construct a hypothesis
Draw conclusions
Test with an experiment








Step 2: Using the below synopsis, match each of the steps of the scientific method to its corresponding statement.

Synopsis: Jenny has been working hard all summer on her tomato garden. Recently, she noticed that
insects have been eating her tomatoes and tomato plants and she is worried about spraying them with harmful, store-bought pesticides.

Jenny states that if she sprays her vegetables with a natural, homemade solution to help fight
the bug problem, then her vegetables will still grow to the same size as they would if she used
store bought pesticides____________________________

Jenny sprays one third of her vegetables with store bought pesticides , one third of her vegetables with her homemade solution, and does not spray the remaining third (her control group) ____________________________

After one week, Jenny compares and tests the differences in her vegetables____________________________

Jenny wonders how she can protect her plants from bugs without harming the
vegetables____________________________

Jenny determines that her homemade solution was just as effective as the store-bought
pesticides____________________________

Jenny goes to the library and looks up different kind of pesticides and their effect on vegetables and also looks up natural remedies to help solve her bug problem____________________________





Identify the independent variable and the dependent variable.

1. Christine investigated how fast one year old Persian cats reacted to different whistles.

Independent Variable ______________________________________________
Dependent Variable _______________________________________________

2. Identify the independent variable, dependent variable, and constants.
Mario studied how far room temperature tap water would spurt out of a plastic milk carton when 3 mm holes were punched at different heights from the bottom of the container.

Independent Variable ______________________________________________
Dependent Variable _______________________________________________
Constants _______________________________________________________
________________________________________________________________

3. Identify the independent variable and dependent variable in each hypothesis.
a. If different motor oils are put in water, then they will float at different heights on the water.

Independent Variable________________________________________
Dependent Variable __________________________________________

b. If the number of twists of a rubber band is increased, then a toy propeller airplane will fly farther.

Independent Variable ________________________________________
Dependent Variable __________________________________________

4. Determine if the hypothesis is supported by the data and explain your answer.
Lamont knew that water made things look larger. He wondered what other liquids such as alcohol and glycerin would do. Lamont thought a pencil would look larger in the thicker liquid (glycerin), followed by water, and then alcohol. In the experiment he rated the increase in pencil size from 1 to 10, with 10 as the largest. His rankings were 7 for glycerin, 5 for water, and 2 for alcohol.

________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________

5. Make a hypothesis about the following using an “If . . . , then . . . “ statement.
a. The time for different size water drops to fall through vegetable oil.
_________________________________________________________
_________________________________________________________
_________________________________________________________

b. How high an ice cube will float in different temperatures of water.
_________________________________________________________
_________________________________________________________
_________________________________________________________

Thursday, 1 August 2013

Safety In the Laboratory

SAFETY IN THE LABORATORY

Entering and leaving the laboratory:
1. Do not run
2. Make sure that school bags are stored safely
3. Put stools under the bench when not in use
4. Leave the bench clean and dry

General Behavior:
1. Do not run in the laboratory
2. Do not eat or drink in the laboratory
3. Work quietly

During Experiment:
1. Never point a tube test containing chemical at anyone, and do not examine the content by looking down the tube.

2. Tell your teacher about any breakage or spillage at once. If you are at all unsure of the practical work, check with your teacher that you are following the correct procedure.

3. Only carry out investigations approved by your teacher, and use the gas, water, and electricity supplies sensibly.

Hazard Warning Symbols

chemistry - checkpoint 
Hazard Warning Symbols

FLAMMABLE
(can easily ignite and burn: benzene, ethanol)











RADIOACTIVE
Give off harmful rays that can kill living cells: uranium, radium
EXPLOSIVE 
Chemicals that explode: toluene
 DANGEROUS FOR THE ENVIRONMENT
Chemicals that may present an immediate or delayed danger to one or more components of the environment
CORROSIVE
Destroy living tissue, including the skin and eyes: concentrated acid, oven cleaner
 OXIDSING
The substance provides oxygen.
Other materials will burn more fiercely in its presence.

 HARMFULL/IRRITANT
Involved a health risk or irritate the skin: dilute acid, alkalis, thinner

TOXIC / POISON 

poisonous if breathed, absorbed through the skin: alcohol, mercury

Tuesday, 28 May 2013

Friday, 24 May 2013

Acids Bases - Checkpoint

FOR CP1
Dear CP1.....Do this worksheet as your assignment. Do this in doc/docx/pdf format. Send it to: markusanth2708@gmail.com). The sooner is better, you will get more extra points :)

ACIDS and BASES WORKSHEET-1
Most people think of acids as corrosive liquids which fizz when they come into contact with solid and burn when they touch the skin. The word acid comes from the latin word acidus meaning sour. As bases neutralise acids they are sometimes described as having properties which are opposite to acids. (Cambridge Checkpoint, Peter D Riley)

Answer the following questions.
  1. Why does wine go sour faster if the cork is removed from the bottle?
  2. How do you think the term of organic acid? Give example.
  3. How is a dilute solution different from a concentrated one?
  4. Which of the following substances are bases – copper chloride, sodium hydroxide, calcium carbonate, magnesium sulphate, copper oxide, lead nitrate, sodium hydrogen carbonate?
  5. Why are bases sometimes described as opposite of acids?
  6. How are acids and bases similar?
  7. Write word equations for the reactions between:

a.      Sulphuric acid and zinc oxide
b.      Hydrochloric acid and calcium hydroxide
c.       Nitric acid and calcium carbonate
d.      Hydrochloric acid and zinc carbonate
8.    How is the neutralisation of a carbonate different from the neutralisation of an oxide or a hydroxide?