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<PLEASE READ!!!! = Welcome to your Yr 10 science assignment information centre (when not in class) for 2011. = = This approach to working on assignments will allow you to develop your skills in resource based learning (RBL), research a topic that is a part of the curriculum and to study and learn with other students. =

To join this wiki, you would have recieved an email with an invitation.
== Once you have signed onto this wiki, you will need to add a page with a name that identifies who you are to your teacher. To add your own page click on "New Page'" icon found on the top left hand column. == == YOUR page is to record an electronic copy of your work that you complete during the research project. In other words, all your work is to be completed on your new page. ==

So again Welcome students of science. Use this page to copy relevant information and to keep in touch with other students and progress on your work. By now you should have printed of a copy of the core information for this term's work (power point presentation) shame if not follow this route on the school's directory: L- drive -- science ---students stavs yr10 class. Print a copy and bring it to class. You should also Save a copy to your own documents folder.

The assignment below is to be completed collaboratively (in groups) and ideally the whole class has the opportunity to help each other, on- line. Complete the table and read the three (3) options to choose from. Only **choose** ONE (1) assignment and work collaboratively to complete. Thao Jenny Christina Chanice || CO2 Inveestigation ||  ||
 * **Group #**
 * & names** || **Topic** || **Learning style** ||
 * 1. ||  ||   ||
 * Troy || Ecosystem Suburbia || Dynamic Learner ||
 * Sean || Ecosystem Suburbia || Innovative Learner ||
 * Alexander || Ecosystem Suburbia || Dynamic Learner ||
 * Alex || Ecosystem Suburbia || Innovative Learner ||
 * 2. || Class debate ||  ||
 * Breana ||  ||   ||
 * Tony ||  ||   ||
 * Ivana ||  ||   ||
 * 3.Amy || Class debate || 1 ||
 * Alicia ||  || 3 & 2 ||
 * 4.Christine || Ecosystem Suburia ||  ||
 * Quinn || Ecosystem suburia || 1 Innovative learner ||
 * Nala || Ecosystem Suburia || 1 innovative Leaner ||
 * 5.Dalena || Creative Writing || 2 ||
 * 6. ||  ||   ||
 * 7.Deni || class debate ||  ||
 * Mirso ||  ||   ||
 * Amra ||  ||   ||
 * Amra ||  ||   ||
 * 7.
 * 6. ||  ||   ||
 * 7.Deni || class debate ||  ||
 * Mirso ||  ||   ||
 * Amra ||  ||   ||
 * Amra ||  ||   ||
 * 7.
 * Amra ||  ||   ||
 * Amra ||  ||   ||
 * 7.







Below is an widget link that can help you reference your work when it comes to completing a bibliography in assignments. It can be used for any source of information; newspapers, text books, internet websites, journals, magazines, CD Rom, encyclopedias, documantries, and so on. Please use it.



=Term 2: Matter= Please view this clip to further assist you to understand matter (atoms, molecules, compounds and mixtures)

media type="youtube" key="sDmMxZJvJFk?fs=1" height="299" width="433"

Read and study this prcedure and assessment prior to entering the laboratory, tomorrow, 11/ 05/ 2011 DUE 25/ 05/ 2011

=**Writing chemical equations**=
 * Chemical equations are a shorthand way of representing chemical reactions. These equations take the form:**
 * reactants --> products**
 * The substances present at the start of a reaction are called the reactants and the new substances formed a called the products.**
 * For example,**
 * The reaction between magnesium and oxygen may be represented as:**
 * magnesium + oxygen > magnesium oxide (word equation)**
 * or**
 * 2Mg + O2 >2 MgO (balanced formula equation)**
 * It is important that you know how to write correct chemical formulas. The following information relates to chemical formulas and how atoms form different substances.**
 * Revision:**
 * **A pure element consists of only one type of atom.**
 * **A compound consists of two or more different atoms, chemically bonded together. **
 * ** ﻿Ions are charged particles. Positive ions are formed when atoms lose electrons and are called cations. ﻿Negative ions are formed when atoms gain electrons and are called anions.   **
 * + 2- **
 * **A polyatomic ion is a charged particle made up of more than one atom, e.g. NH4 & CO3**

Atoms of the noble gases (Group viii) exist by themselves. For this reason, we say their molecules are monatomic. For carbon dioxide, a molecule consists of one carbon atom and two oxygen atoms covalently bonded together and has a molecular formula CO2. The molecular formula represents the actual number and type of atoms in a compound. A diatomic molecule consists of two non metals atoms covalently bonded. Elements that exist as diatomic molecules at SLC are hydrogen ( H2), oxygen (O2), nitrogen (N2), fluorine(F2), chlorine(Cl2), bromine(Br2), and iodine(I2).
 * Pure Metals: **
 * The bonding within metals is called metallic bonding
 * All metals are solid at SLC (Standard Laboratory Conditions, 25 degrees Celsius and 1 atmosphere pressure), except mercury, which is liquid.
 * Covalent bonding:**
 * Covalent bonding is the sharing of electrons and occurs only between non metals like carbon and oxygen.
 * A molecule is composed of non- metals and is a specific number of atoms bonded together.


 * Ionic bonding:**
 * Ionic bonding involves mainly a metal combined with a non- metal. Ionic compounds are crystalline solids at SLC, unless dissolved in water as an aqueous solution.
 * The formula of an ionic compound is not a molecular formula, since ionic compounds form crystal lattices, not molecules. It simply shows the ratio of positive and negative ions in the crystal. For example, the ionic compound, magnesium oxide (MgO). This doesn't mean that one atom of magnesium and one atom of oxygen move around together, it just means that, in any sample of magnesium oxide, the ratio of magnesium ions to oxide ions is 1: 1. A small crystal may contain a million magnesium ions and a million oxide ions, whil;e a larger crystal may a trillion magnesium ions and a trillion oxide ions. Either way, the formula is always MgO.
 * If, in a formula, more than one of a polyatomic ion is needed, brackets should be used, for example, Fe2(SO4)3, Ca(OH)2, (NH4)CO3

=**Balancing chemical equations.**= Let's take a look at the reaction between magnesium and hydrochloric acid.

Mg + 2HCl --> MgCl 2 + H 2 (balanced)
Within this equation there are numbers like the pink 2, (normally a subscript) and a large 2, like the one in front of the formula for HCl. The pink numbers show many particular number of atoms or ions are in the formula and if there is no number after an atom or ion it means that there is only one atom or ion in the formula. The formula MgCl 2 shows us that magnesium chloride is made up of one magnesium ion and two chloride ions. H 2 shows that hydrogen gas is made up of two hydrogen atoms chemically bonded together.

The larger numbers in front of formulas are used to balance the equation. **__The Law of Conservation of Matter__** states that matter can neither be created nor destroyed ; it can only be changed from one form to another. This means that there must be the same number of a particular type of atom on each side of the equation. The atoms re- arrange.

So the unbalanced equation for the above reaction is

Mg + HCl --> MgCl 2 + H 2 (unbalanced)
To balance the reaction, look at each element in turn and add numbers in front of the formulas so that there is the same number of that type of atom on both sides.The pink numbers (subscript numbers) must not be altered. Start with magnesium, there is one magnesium atom on each side so balancing is not required. Hydrogen has one atom on the left hand side and two hydrogen atoms on the right hand side, therefore it requires balancing. A large two is written in front of the HCl making the H balanced with 2 on each side. This also balances the chlorines aswell with tow atoms on each side.

Now balance the reaction between sodium carbonate and nitric acid that produces sodium nitrate, water and carbon dioxide.
 * step 1 : write the word equation for this reaction


 * step 2 : write the unbalanced formula equation.

Na2CO3 + HNO3 ---> NaNO3 + H2O + CO2
 * step 3 : look at each element in turn, adding numbers in front of formulas where needed to get the same number of atoms on each side of the equation

Na (sodium); two on the left but only one on the right, therefore '2' in front of NaNO3 (sodium nitrate)

C (carbon); no balancing required O (oxygen): six on the left and nine on the right so placing a '2' in front of the nitric acid (HNO3) gives a balance outcome. H (hydrogen): two on each side due to the previous step, and this often happens N (nitrogen): two on each side also. So, the final balanced equation is: Na2CO3 + 2 HNO3 ---> 2 NaNO3 + H2O + CO2

Often there will be __trial and error__ before finding the __right combination__ of numbers to __balance the atoms__ of the left with the atoms of the right. Try balancing this equation: Al2O3 + C -> CO + Al.
 * Questions to be completed either in your book or on your wiki page.**

1. Which of the following are molecules a) CO2 b) H2O c) NaCl d) LiCO3 e) N2 f) CaO g) Ar

2. Write the chemical formula for the following substances and state whether they are metallic, ionic, or covalent. a) magnesium b) strontium sulphate c) oxygen gas d) carbon monoxide e) calcium chloride f) sulphur dioxide

3. Why is Na2SO4 not a molecular formula but H2O is?

4. When are small subscript numbers used in chemical equations, and when are normal sized numbers used.

5. What conditions does SLC represent?

6. Why is it necessary to balance equations?

7. What is the difference between NaCl (s) & NaCl (aq)

8. Balance the following equations: a) H2 (g) + O2 (g) -> H2O (l) b) KClO3 (s) --> KCl (s) + O2 (g) c) CH4 (g) + O2 --> CO2 (g) + H2O (l)

d) BaO (s) + HNO3 (aq) --> Ba(NO3)2 (aq) + H2O (l)

e) Pb3O4 (s) > PbO (s) + O2 (g)

9. Blance the following equations and add the missing states.

a) Na + Cl2 ---> NaCl (s)

b) CaCO3 (s) ---> CaO (s) + CO2

c) P4(s) + O2 -> P2O5 (s)

d) Pb(NO3) (s) > PbO (s) + NO2 (g) + O2

10. For each of the following reactions, i) write the word equations ii) write the balanced formula equation including states.

a) dilute sodium hydroxide solution is added to dilute sulphuric acid, producing sodium sulphate and water

b) Nitrogen gas is added to hydrogen gas, producing ammonia (NH3) gas.

c) Carbon monoxide gas combines with oxygen to form carbon dioxide gas.

d) Solid iron combines with chlorine gas to produce solid iron (III) chloride

EXTENSION

Draw a diagram to show how the ions are arranged in a crystal of

a) Magnesium oxide.

b) sodium chloride. =**Stoichiometry(The maths in chemistry)**=
 * Lets say we wanted to weigh out a 10 water molecules. Ten water molecule together are too small to weigh and that is why chemists deal with very large numbers of atoms, ions and molecules by using a term called 'the mole' .**
 * If you weighed a drop of water, you would have weighed the mass of billions of water molecules (due to them being so small). To speak of the actual number can get very confusing and so a more convenient way of counting in chemistry is needed and that's where the mole comes in.**
 * The atomic mass that can be found on most periodic tables is the mass of 1 mole of substance of those atoms . Tellurium for example has an atomic mass of 127.6. This is the mass in grams of a very large number (called a mole) of atoms of that type.**
 * The mass of one mole of carbon atoms is 12 grams and the mass of one mole of oxygen atoms is 16 rgrams. **
 * The number of atoms in a mole is 6.02 E 23 and is called Avogadro's number .**
 * A mole is used in the same way you may use the term a dozen or a couple referring to 12 or 2 respectively. A dozen people meaning 12 people and a mole of people meaning 6.02 E23 people (a very large number).**
 * The mole is very useful in chemistry because it quantifies the number of atoms or ions or molecules that are involved in a given reaction or process and therefore can be measured out.**
 * Using balanced chemical equations aswell as data from the periodic table it is possible to calculate exactly what mass of reactant should produce a certain mass of product .**
 * Questions:**
 * 1. What is a mole (in chemistry)?**
 * 2. How many:**
 * a) socks in a pair of socks**
 * b) eggs are in a dozen eggs**
 * c) atoms ar in a mole of gold**
 * d) H20 molecules are in a mole of water**
 * e) dozens of eggs are in a mole of eggs**
 * f) pairs of socks are in a mole of socks**
 * 3. How is the mole useful in chemistry?**

** Practical: reactivity of metals & balancing equations . Wednesday 25/ 05/ 2011- lab. report due 01/ 06/ 2011**

 * This Wednesday 25/ 05/ 2011 we will be investigating the reactivity of certain metals (zinc, aluminium, copper, lead, magnesium, iron, & tin) when reacted with acid. The acids used will be sulphuric acid (H2SO4) and hydrochloric acid (HCl). From our observations we will determine which metal is most reactive and an reactivity series ( from least reactive to most reactive ) will be constructed based on your results.**
 * Record your results in a table.**
 * Metal || HCl || H2SO4 ||
 * zinc ||  ||   ||
 * aluminium ||  ||   ||
 * copper ||  ||   ||
 * lead ||  ||   ||
 * magnesium ||  ||   ||
 * iron ||  ||   ||
 * tin ||  ||   ||
 * You will compare your results with either an on line or text book source to compare the accuracy of your results. Also compare with other groups in the classroom!**
 * Write the symbols of each metal.
 * Write the symbols of each metal.


 * **Comment on the reactivity of the metal and its position in the periodic table. Do you notice any trend?**
 * **Write balanced equations for each reaction including the states .**
 * **What gas was formed from the reaction. What simple test did you conduct to determine this?**


 * The more reactive metals tend to corrode easily. Less reactive metals show little corrosion. Give examples of some metals and there use in everyday life and relate this to their properties or reactivity series.**