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					QUESTION ONE:                           Atomic Structure
        (a)        A neutral atom of aluminium has an atomic number of 13 and an atomic mass of 27.

        (i)        How many protons are there in the nucleus of the neutral aluminium atom?


        (ii)       How many neutrons are there in the neutral aluminium atom?


        (iii)      How many electrons will the aluminium atom lose to form an aluminium ion?




        (b)        How many atoms are present in Zn(HCO3)2 ?


        (c)        How many elements are present in Zn(HCO3)2 ?


        (d)        How many atoms are there in 2 K2SO4


        The pH values of four substances are given below:
               Sulfuric acid                             pH = 1
           Lemonade                             pH = 4
           NaHCO3 solution                      pH = 9
           (e) When red and blue litmus paper is added to these three solutions what would be
           observed?
           (i)    Sulfuric acid

(ii)       Lemonade

           (iii)      NaHCO3 solution

            (f)    When Universal Indicator solution is added to each of these substances, what
           colour would result?
           (i)     Sulfuric acid

(iii)      Lemonade

           (iii)      NaHCO3 solution
                 1                               PERIODIC TABLE                                                          2
         H                                                                                                      He
      hydrogen                                                                                                  helium
                 1                                                                                                      4
                 3                 4             5              6               7            8              9          10
        Li              Be                B            C               N             O             F            Ne
       lithium         beryllium         boron        carbon         nitrogen       oxygen       fluorine       neon
                 7             9              11            12             14            16             19             20
                 11           12              13            14             15            16             17             18
        Na              Mg               Al            Si              P             S            Cl            Ar
       sodium         magnesium        aluminium      silicon       phosporus       sulfer       chlorine       argon
                 23           24              27            28             31            32             35             40
                 19           20
         K              Ca                                                      6            atomic number
                                                   symbol
      potassium        calcium                      name               C
                 39           40                                     carbon
                                                                           12                mass number

Question 2. Use the Periodic Table provided to help you answer this question.
      What is the:
(a) atomic number of fluorine?

(b)   mass number of phosporus?

(c)   symbol for potassium?

(d) What is the name of the atom with a mass of 14?

(e) Explain how you can use the atomic number and mass number of argon to determine the
    number of neutrons that it has.




(f) Copy and complete the diagram to show how the
electrons would be arranged around the nucleus of this atom.



                                                                                                                 S
(g) Explain why the charge on the S ion is -2.
QUESTION THREE:
(a)      A sample of oven cleaner out of a can has a pH = 11.
     (i)    What does this tell you about the nature of oven cleaner?

       (ii)      Explain your answer to (i).




(b)            When baking soda (NaHCO3) is added to a sample of vinegar a reaction occurs.
       (i)       Give the names of the elements present in baking soda.

       (ii)      State what would be observed as the reaction proceeds.


       (iii)     Name two products of the reaction between baking soda and vinegar.




(c) The formula for magnesium chloride is MgCl2. If the charge on the magnesium ion is 2+
(Mg2+) explain how we can determine the charge on the chloride ion.




(d) A potassium atom has 19 electrons. What is its electron configuration?


(e) A neon atom has 10 electrons.
(i) What is its electron configuration?


(ii) Explain why (using your answer to (i)) neon is unreactive.
Mighty Metals
Copper, magnesium and aluminium metals have a number of uses in aircraft construction

1. Name a physical property of aluminium that makes it suitable for use in aircraft.



2. Name a chemical property of aluminium that makes it useful for aircraft construction.



3. Write the equation for the reaction of magnesium and hydrochloric acid




Magnesium is used in emergency signaling flares

4. Explain why the chemical properties of magnesium metal make it useful for emergency
   signaling flares.




5. Discus why aluminium is used as a bare metal, while iron is often painted before use.
   In your discussion, relate the chemical properties of iron and aluminium to named uses.




Fiona has found two unlabelled objects A and B. She knows that one is a metal and the other is
not. She listed some properties of the objects in the table below.

                                            Objects
                                                  A             B
                         Appearance                         Dull, black
                         Conductivity of
                                                  Good
                         heat
                         Malleability             Good        Brittle

1. Predict which of A or B Is the metal.

2. Predict the appearance of A.
   Marble is a rock made up of the compound Calcium Carbonate
   Geologists test to see if a rock is marble by placing a drop of hydrochloric
    acid on the rock.

    1. What are the products of the reaction above?


    2. Describe what the geologist might observe to confirm that a rock is Calcium Carbonate.




    3. Explain how acid rain would damage a marble statue




Upset tummy.
1. Give the name and formula of the metal compound formed when sulfuric acid reacts with
   sodium hydroxide.

    Name:

    Formula:

2. Magnesium hydroxide is a component of some antacid tablets. Name the two
    products of the reaction between magnesium hydroxide and hydrochloric acid
    found in the stomach.



3. Holly takes a beaker with 50 mL of water, stirs in a crushed antacid tablet and adds a
    little universal indicator. She then adds Hydrochloric acid drop by drop and notes that
    the colour of the solution changes from blue to green to red.
    Explain the colour changes above in terms of the substances added to the beaker and the
     products of their reaction
1.      Copper and aluminium metals have a number of uses around the home. One use of
        copper metal is in kitchen saucepans.
(a)     Name TWO physical properties of copper that make it suitable for use in saucepans.

Copper metal can react with oxygen in the air.
(b)     Write a word equation for the reaction of copper with oxygen.

Copper can also be used for water pipes.
(c)     Explain why the chemical properties of copper metal make it able to be used for water
        pipes.



(d)     Another metal is calcium. Both aluminium and calcium are high on the reactivity series.
        Discuss why aluminium is often used as pure metal while calcium is not usually used as a
        pure metal.




2.      Fiona has found two unlabelled solution bottles. She knows that one is sulfuric acid and
        the other sodium hydroxide. She decides to test the two solutions to find out which is the
        acid. She has a dropper bottle containing universal indicator.

(a)     Describe how Fiona could identify which bottle contains acid.


Fiona’s teacher told her that another bottle contains a solution of potassium hydroxide.
(b)     Describe and explain what Fiona would observe if she added both red and blue litmus to
        potassium hydroxide.




Below is the pH scale.
       1                                       7                                     14
      red        orange                            green             blue                  purple

An unknown chemical turns yellow when a few drops of universal indicator are added.
      (c)   What would be the predicted pH?
      (d)   What does the yellow colour tell you about the unknown chemical?
                                    Ions: Mg2+ O2- H+ Cl-
Magnesium is often used in school laboratories because it is a reactive metal.
   a) Name TWO metals that are more reactive than magnesium.


   b) Magnesium metal burns well in air.
   (i)    Write a word equation for this reaction


   (ii)   Write a balanced chemical equation for this reaction.


   c) Magnesium metal also reacts with hydrochloric acid.
   (i)    Write a word equation for this reaction


   (ii)   Write a balanced chemical equation for this reaction.


   d) Discuss what would happen to the pH of the acid solution in c) as more magnesium is
      added. Your answer should refer to the species present and what is happening in the
      reaction.




   e) Some students are making jewellery in their technology classes. They need to choose a
      suitable metal to make a bracelet. One student, Terri, decides to use magnesium because
      it is very light. Another, Fred, says he thinks that copper would be much better because it
      is a good conductor of heat.
Discuss the suitability of each metal for making a bracelet. Refer to the ideas of Terri and Fred
and use other properties of magnesium and copper in your answer.
                              Ions: Mg2+ Ca2+ CO32- OH-        H+    Cl-
Increased concentrations of acid in the stomach can cause indigestion.
   a) Describe what will happen to the pH value of the stomach contents when the
      concentration of acid in the stomach is increased.


   “AntiAcid” is an antacid in tablet form for treating indigestion. The antacid treatment can
   neutralise the acid. The antacid treatment tablet contains the two metal compounds,
   magnesium hydroxide and calcium carbonate.
   b) Give the formula for:
   (i) Calcium carbonate                         (ii) magnesium hydroxide

   c) What would be observed when calcium carbonate and acid react together?



   d) What colour would litmus solution turn when drops of it are put onto some magnesium
      hydroxide? Give a reason for your answer.



   Stomach acid is hydrochloric acid.
   e) Write a balanced equation for the reaction of calcium carbonate with stomach acid



   Discuss why the reaction between magnesium hydroxide and stomach acid (hydrochloric
   acid) can be called a neutralization reaction. You may use equations in your answer and you
   should refer to the species present.
Scrap metal dealers buy unwanted metal items and, after sorting them, sell them to foundries
where the metals are melted down and made into new useful items.
(a)   State TWO physical properties of metals.


(b)   A common item in the scrap metal yard is the car
      radiator. Most are made of either aluminium or
      copper.
      When a customer brings in a radiator, the scrap
      metal merchant must be able to recognise the metal
       it is made of.            This old car radiator could be
                                   made of aluminium or copper.

       (i) Copy and complete the table below to show the
      properties of aluminium and copper that can be used
      to tell them apart.
       Property                     Aluminium                     Copper
       Colour
                                    Low                           Moderate
      The radiator is part of the car’s cooling system. Water circulates round the hot engine, then
      passes through the many narrow tubes of the radiator where it cools.
      (ii) Discuss the suitability of these two metals for use in car radiators.




(d)    Sodium metal is too reactive for common use because it reacts with water.
      (i) What gas is produced when sodium reacts with water?


      When a small piece of sodium metal is dropped into a
      beaker of water containing litmus solution, a dark blue
      trail is left where the sodium has been (as shown in
      the photograph).
      (ii) Account for the formation of the blue trail.




      (iii) Write a balanced chemical equation for the reaction between sodium and water.
An element has an atomic number of 16 and a mass number of 32.
(a)       Name the element.
              (i)   Complete the table showing the number of protons, neutrons and electron in an atom
                    of this element.
                    Number of protons         Number of neutrons         Number of electons


          (ii)      In what group of the Periodic Table is this element found?
      (iii)         What is the charge on the ion formed by this element? Give a reason for your answer.



(b)       A particle of element    X
                                  has 13 protons, 14 neutrons and 10 electrons.
          (i) Write the electron configuration for this particle.

          (ii) Complete the symbol for particle     X showing its atomic number, mass number and
          charge (if any).




                                   X
(c)       Household bleach is a dilute solution of sodium hypochlorite, NaOCl.
          The hypochlorite ion is also found in calcium hypochlorite (bleaching powder) which is used
          to kill microbes in swimming pools.
          Use the Table of ions in your book to write the symbol/formula for
          (i) the sodium ion                         (ii)   the hypochlorite ion

          (iii)     calcium hypochlorite

(b)       Household bleach reacts with acidic liquids to release poisonous chlorine gas. This is a
          particular hazard in the bathroom, because some shower and toilet cleaners are acidic.
          (i)       The table below shows the pH values of certain bathroom products.

                               Sani-blue Plus     Chemseptic        Liquiscrub          Bufferall
          pH                        11.5             7.0                9.0               2.5

          (i)       Which product is not suitable to use with bleach?
          The bathroom cleaners listed above were tested using pieces of red and blue litmus paper.
          (ii)      Copy and complete the following table showing the colour of each piece of litmus
                    paper AFTER it had been dipped into the cleaner.
                                      Sani-blue Plus    Chemseptic      Liquiscrub      Bufferall
 Colour of red litmus paper
 Colour of blue litmus paper
A scientist investigating the site of an ancient civilisation finds 6 objects (A – F). She analyses
the objects and sends her notes back to the University she works for. Unfortunately some of the
information she collected was lost. The table below shows the information that was received. A
blank square indicates there was no information available for that particular property.
        Objects       Appearance             Conductivity     Conductivity     Malleability
                                             of heat          of electricity
        A             Shiny, brown                            Good
        B                                    Good                              Good
        C                                    Good             Poor             Brittle
        D             Dull surface, shiny                     Good
                      when cut
        E                                    Good                              Good
        F             Dull black surface                      Good             Brittle
Assuming the objects were made from elements, use the information given above to identify if
   they are metals or non-metals.




Copper is used for electrical wires. Give 2 physical reasons and 1 chemical reason why wire is
  suitable for this purpose.



Iron nails are often galvanized. Explain what the process of galvanizing involves and how the
    process works.




 Give the name and formula of the metal compound formed when sulfuric acid reacts
      with calcium hydroxide.


5. Magnesium hydroxide tablets are used to reduce stomach acidity.
a) What happens to the pH of an acid solution when Magnesium hydroxide is added?


b) Write a balanced chemical equation for the reaction between magnesium hydroxide and
hydrochloric acid (stomach acid)
                                  Reactivty Series of Metals
                                   Name                  Symbol
                                  Sodium                    Na
                                  Calcium                   Ca
                                Magnesium                   Mg
                                Aluminium                   Al
                                    Zinc                    Zn
                                    Iron                    Fe
                                   Lead                     Pb
                                  Copper                    Cu

A manufacturer of Mountain bikes decided to make the frames out of Aluminium.
a) Give a physical reason and a chemical reason why Aluminium is suitable for making bike
   frames out of.




The manufacturer decided to use either Magnesium or Zinc to coat his Aluminium frames with.
Use the reactivity series given above to answer the following questions.
b) Which would be the best metal (out of Zinc or Magnesium) to coat the frames with?


c) The reason that the metal based paint I chose in b) is the best is because;



d) Why wouldn’t sodium be a suitable metal to use as a coating for the mountain bike frames?



When the manufacturer went to his warehouse to get the metal he had chosen he discovered
that a water leak had caused the labels on 4 boxes of different metals to wash off. He decided to
find out which was which by carrying out a series of tests.
He discovered:
       Metal A did not react with hot or cold water or dilute hydrochloric acid.
       Metal B reacts with hydrochloric acid but not water
       Metal C reacts with hydrochloric acid and reacts slowly with hot water.
       Metal D reacts with hydrochloric acid, hot water and cold water.
e) If the four boxes originally contained zinc, copper, calcium and magnesium match the box to
   its contents.
Positive Ions                                      Negative Ions
   1+                2   +
                                     3 +
                                                       1-                   2-             3-

    H1+             Fe2+            Fe3+                 Cl1-            CO32-            PO43-
  hydrogen      Iron (II) ion   Iron (III) ion       Chloride ion      Carbonate        Phosphate
    ion                                                                   ion              ion
    K1+            Mg2+            Al3+                NO31-              O2-
 Potassium      Magnesium       Aluminium            Nitrate ion       oxide ion
    ion             ion            ion
    Na1+           Ca2+                                HCO31-              S2-
 Sodium ion     Calcium ion                      hydrogen carbonate    Sulfide ion
                                                         ion
   NH41+            Zn2+                                OH1-             SO42-
 Ammonium         Zinc ion                          Hydroxide ion      Sulfate ion
      ion
     Ag1+          Pb2+
  Silver ion     Lead ion
                   Cu2+
                Copper (II)
                   ion

Identify the following ionic compounds.
a) Ca(Cl)2                                  b) Pb(OH)2                     c) Al2O3


Use the table of ions provided to give the formula for the following ionic compounds.
a) Calcium carbonate                             b) Sodium chloride


c) Iron(III) hydroxide                           d) Copper nitrate


Name the products for the following reactions
a) Iron + oxygen gas

b) Zinc + hydrochloric acid

c) Copper oxide + nitric acid

Name the reactants that where reacted together to form the following products.

a) Lead sulfate, carbon dioxide and water


b) Calcium chloride + hydrogen gas
Kieran had an iron can covered with rust (iron (II) oxide). He decided to clean the can by dipping
it into a beaker of dilute hydrochloric acid. He figured that the acid would eat through the rust
layer first. The acid solution contained a few drops of universal indicator.
     When he carried out the experiment he made the following observation:
    The colour of the solution changed to a green colour.
    No gas was given off.
a) What does the (II) in the expression iron (II) oxide mean?


b) What was the original colour of the acid solution with universal indicator?

c) Give a word equation to describe the reaction that was occurring


c) Write a balanced chemical equation for the reaction.



Kieran noticed that the rust was gone from the iron can. However he decided to add some
sulfuric acid to the beaker containing the can. When he did so he observed that
1.      The solutions colour changed to a bright red.
2.      After a few minutes, bubbles of gas started to be given off.
3.      A white solid began to form on the sides of the can.
4.      After a few more minutes the bubbles stopped.
5.      The solution had changed to a slightly pink colour.
d) For each statement explain the observations given




e) Describe the chemical test used to test for the gas produced in the reaction above
The word equation for a chemical reaction is given below

                   Acid + Base                    A metal salt + water
   a) Give a definition of the word base



   b) Copy and complete the general word equations given below
   (i)    Acid + Metal Carbonate

   (ii)   Acid + Metal


   c) Describe the chemical test used to test for the gas produced in the acid + carbonate
      reaction.




Corrosion (rusting) occurs more rapidly in areas where the air is polluted. This is because when
non-metals such as carbon or sulfur are burnt they form non-metal oxides that react with water in
the atmosphere to form a weak acid solution (acid rain)
   d) What is the (approximate) pH of the weakly acidic acid rain.


The acid rain that falls eats away at limestone buildings and statues. This is because limestone
is made up of calcium carbonate.
   e) Write a balanced equation for the reaction that occurs between the calcium carbonate in
      the statues and sulfuric acid (which is one of the acids in acid rain)
   (Hint: Write a word equation first and continue from that)




   f) A student was asked to prepare a solution of lead chloride. Write a word equation for the
      formation of lead chloride from an appropriate acid and another suitable substance.
QUESTION ONE: ATOMIC STRUCTURE
You will need to use the Periodic Table and the Table of Ions to answer these questions.
(a) Copy and complete the table below by putting the appropriate numbers or symbols into all

   the boxes.

                                                                    Electron     Mass
     Name         Symbol     Protons    Neutrons    Electrons
                                                                  arrangement   number

   Aluminium                                                                     27

     Argon                                 22

    Chloride
                                                                                 35
      ion


(b) Explain why the magnesium ion has a 2+ charge.




(c) Complete the table below by putting in the appropriate name or compound formula.

                                             Your answers below
         Magnesium
          hydroxide
         Ca(HCO3)2

         Lead nitrate

             Li2SO4

     Iron (III) carbonate

             BaCl2

(d) How many atoms of oxygen are there in the formula Al2(CO3)3?


(e) What is the total number of atoms in the formula Al2(CO3)3?
QUESTION TWO: METALS AND COMPOUNDS
(a) Sebastian was required to investigate physical properties of two different substances.
    Substance A was calcium and substance B was calcium carbonate (limestone).

   Sebastian said calcium was a ductile substance Describe what this means.



(b) Discuss how both substances would behave when
    connected to an electrical circuit as shown. Give
    reasons for their behaviour.
                                                                                   Substance

                                                                             A




(c) Explain why calcium is not a suitable metal to use in an electrical circuit.




(d) Both substances A and B can be used to make calcium chloride.
    Write a word equation for the reaction of calcium carbonate that will form calcium chloride.




It is not recommended for calcium to be put into acid. However it can be put into water
relatively safely. A piece of calcium is put into water containing universal indicator.

(e) Describe the colour of the universal indicator before the calcium was put in.



(f) Write a balanced symbol equation for the reaction of calcium with water (universal indicator
    is not included in the equation).
(g) Describe and explain the observations you would make as the reaction proceeds and relate
    them to the chemical changes taking place.




(h) Lead is used within the keels of boats and aluminium is used for a   number of the fittings on
the boat.

Pure aluminium is much more reactive than pure lead.

Discuss two reasons (one physical and one chemical) why aluminium is a suitable metal for the
fittings.
     Physical reason




   Chemical reason




(i) Explain two reasons (one physical and one chemical) why lead is used for the keel.
   Physical reason




   Chemical reason
QUESTION THREE: ACIDS AND BASES


Mohutu and Chi are in their baking class. The first task of
the day is to follow a recipe to make a banana cake.

The ingredients in the recipe are shown below.
      Flour           bananas                    baking powder       baking soda
      eggs            water                      Milk                butter
      vanilla essence

(a) At the end of the lesson, Mohutu says their cake is too hard. Chi points out the obvious, that
    the cake had not risen.

   Which ingredient(s) did the students probably leave out of their cake?




(b) One of the listed ingredients is called baking soda. What is its chemical name?



(c) Early in the recipe the mashed bananas are mixed with warm milk. This mixture is weakly
    acidic. What would be the observation if two types of litmus paper (red and blue) were dipped
    into this milk-banana mixture?

   Red litmus paper

   Blue litmus paper

(d) Describe the pH of the milk solution



(e) Describe what happens when this weakly acidic mixture comes in contact with baking soda in
    the cake recipe. Explain your observations.




(f) In another lesson, Mohutu and Chi had to cook eggs in an iron frying pan.
    Give reasons why iron is a suitable material for use in a frying pan.

				
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