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    Topic overview in a mindmap 

    This mind map is being put together by students and will grow with time
    Chemistry & cooking by Magnus Drechsler

    1.2 The Mole Concept 

    Understanding

    1. The mole is a fixed number of particles and refers to the amount, n, of substance
    2. Masses of atoms are compared on a scale relative to 12C and are expressed as relative atomic mass (Ar) and relative formula/molecular mass (Mr).
    3. Molar mass (M) has the units g mol–1.
    4. The empirical and molecular formula of a compound give the simplest ratio and the actual number of atoms present in a molecule respectively.

    Applications and skills

    ​
    1. Calculation of the molar masses of atoms, ions, molecules, formula units.
    2. Solution of problems involving the relationship between the number of particles, the amount of substance in moles, and the mass in grams.
    3. Interconversion of the percentage composition by mass and the empirical formula.
    4. Determination of the molecular formula of a compound from its empirical formula and molar mass.
    5. Obtaining and using experimental data for deriving empirical formulas from reactions involving mass changes

    Inquiry questions 

    1.2 What is the definition of the empirical and molecular formula?
    1.2 How can the empirical formula determined experimentally?
    ​
    ​1.2 How can interconvert between empirical formula and percentage composition 
    Flipped classroom 

    Introducing and calculating relative atomic mass 

    These videos explains what relative atomic mass is and why this mass is relative and what it is relative to. It also recaps on what an isotope is an and how to calculate the relative atomic mass using abundance data of these isotopes. 
    Write down the definition of relative atomic mass and follow the example calculation.
    ​
    ​After watching the video complete the quiz.

    Molecules in cooking​ 

    Food has a number of basic molecules such as:
    ​

    ​​Fats (triglyceride)

    ​Carbohydrates (sucrose)
    Protein 

    U.2 + AS.1 - Exercise - Relative formula Mass:

    1. Identify the number of carbon, hydrogen and oxygen atoms the the carbohydrate molecule.
    2. Determine the relative formula mass Mr of Sucrose.
    Picture
    Sucrose (Ball and stick diagram)
    Syllabus points addressed: 
    U.2: Masses of atoms are compared on a scale relative to 12C and are expressed as relative atomic mass (Ar) and relative formula/molecular mass (Mr).
    ​
    AS.1: Calculation of the molar masses of atoms, ions, molecules, formula units.

    P1 - Practical - Food test (Review from MYP - Middle school) 

    This parctical you would probably have done already in middle school. This is just a nice investigation of the food molecules that we will be talking about quite a bit. 

    Chemistry behind the tests

    Please note that some of the chemistry is discussed in later units and novel at this point. 

    Fats 

    Picture
    triglyceride
    Bromine water test 
    As you can see in the structure above triglycerides contain alkenes and the Bromine water test is used to detect those bonds.

    Carbohydrates 

    Benedict test
    So for the Benedict test to be positive we need aldehydes. Maltose as displayed above does not have any aldehydes but the ring close and open ring structure that has an aldehyde are in equilibrium. 
    ​ 
    Picture
    https://en.wikipedia.org/wiki/Reducing_sugar
    During the benedict test a redox reaction takes place. The Cu in the benedict solution is reduced and the aldehyde in the open ring structure is oxidised

    Reaction equation:
    Picture
    https://en.wikipedia.org/wiki/Benedict%27s_reagent

    Explaining results 

    Task:
    ​

    Avogadro's number 

    Just like there are 12 apples in a dozen of apples there are 6.02x10^23 atoms in 1 mole. This is important for the next exercise.

    U.1 + AS.2 - Exercise - Number of particles to number of moles using avogadro's numbers:

    1. Complete worked solution on the Pearson textbook p16/17
    2. If you have 2x10^23 triglyceride and 8x10^23 sucrose molecules in your food item, identify how many moles of Oxygen atoms would be present.
    Syllabus points addressed:
    U.1: The mole is a fixed number of particles and refers to the amount, n, of substance

    AS.2: Solution of problems involving the relationship between the number of particles, the amount of substance in moles, and the mass in grams.

    Relative formula mass and molar mass 

    Converting between Grams and Moles 

    Converting between moles, atoms and molecules 

    U.3 + AS.2 - Exercise - Mass to number of moles and number of atoms using avogadro's numbers and molar mass

    Complete worked examples in the Pearson textbook page 20
    See to the right a nutrition label that you would find on your food that you buy from a grocery shop.
    1. Identify how much g of carbohydrates, protein and fat there is in a serving size of 75g.
    2. Determine the amount of a) moles and b) atoms of the carbohydrates, protein and fat.
    Picture
    Nutrition label showing the food ingredients (https://www.fda.gov/food/new-nutrition-facts-label/calories-new-nutrition-facts-label)
    Syllabus points addressed:
    U.3: Molar mass (M) has the units g mol–1.

    AS.2: ​Solution of problems involving the relationship between the number of particles, the amount of substance in moles, and the mass in grams.
    blended learning

    U.3 + AS.2 - Nutrition label calculation - student presentation 

    Sketchnoting poster example

    Video of student presentation example 
    Picture
    Artist: Fatin Muhamed Zulkhibri (Student work)
    Student work 

    Practice what you have learned

    Differentiation by outcome:
    All: Pearson Textbook - Exercise: 13-15 p17 + 16-23 p 21
    Most: Oxford Textbook - Quick questions: 1-3 p17-18
    Some: Silberberg Textbook - SL Ch 1: 3, 4, 7, 8, 19, 24, 39, 40, 53
    Additional explanation from Havard X 

    AS.5 - Determining the empirical formula experimentally (IB Prescribed practical)

    There are 2 practicals that are determining both the empirical formula of a compound.
    Raw data:
    Follow the instruction, record your data and answer any question on the practical sheet. Fill in your raw data in the form and get your and other students data form the spreadsheet to analyse. 
    Processed data
    1.  Determine the mean of your and other students data 
    2. Calculate the mass of magnesium and oxygen 
    3.  Using the practical sheet follow the steps to determine the empirical formula of Magnesium oxide

    Cooking to introduce Percentage composition

    This is a recipe that we are going to use in our cooking lab later on. This recipe does not use animal fats or proteins. Let's look at the recipe in more detail having percentage composition in mind.  
    Ingredients
    • 1 1/2 Cups/252.2g flour (all-purpose)
    • 3 Tbsp./45g cocoa (unsweetened) 
    • 1 Cup sugar/201.6g (All purpose sugar – Granulated Pure Cane Sugar)
    • 1 tsp./4.2g baking soda
    • 1/2 tsp./2.1g  salt
    • 1 tsp./4.2g white vinegar
    • 1 tsp./4.2g pure vanilla extract
    • 5 Tbsp./75g vegetable oil
    • 1 Cup/201.6g water
    Inquiry task 
    1. Calculate the total mass of the ingredients 
    2. Determine how much percent of the total mass is the vegetable oil, flour and sugar. 
    3. Identify the ratio between vegetable oil, flour and sugar
    Differentiation by task:
    If you are stuck and need help use the videos below and apply the theory to this real life problem. 
    Picture
    https://sweetlittlebluebird.com/tried-true-tuesday-crazy-cake-no-eggs/

    AS.3 - Percentage composition 

    Videos explain how to determine the empirical formula using the percentage composition. 

    AS.3 - Percentage composition 

    Complete worked examples in the Pearson textbook page 22 - 25
    Comparing percentage compositions in food molecules - Blog 
    Task 1: Research and select any food molecule (not too large) 
    Task 2: Find a picture of the full structural or skeletal formula 
    Task 3: Determine the percentage by mass of C, H and O in the compound
    ​Task 4: Explain your calculations in the blog by commenting to the post that you can access using the button below 
    Task 5: Reply to  another students post and give feedback on 
    1. Accuracy of calculation 
    2. Clarity of their explanation 
    3. Suggest improvements or needed corrections 
    Picture
    Example of food molecule: Triglyceride (fat)
    Picture
    (https://www.flickr.com/photos/dj-dwayne/4652345168)
    Syllabus point addressed:
    AS.3: Interconversion of the percentage composition by mass and the empirical formula.

    Skills-based Inquiry questions

    1.2 How can you interconvert between empirical formula and percentage composition?
    ​1.2 How can the empirical formula be determined experimentally?
    Flipped classroom

    U.4 + AS.4 - Empirical and molecular Formula 

    The video explains the difference between the molecular and empirical formula. It demonstrates how to derive the empirical formula from the molecular formula, giving a number of examples. 
    Watch the videos and complete the quiz

    Determine the empirical formula 

    Calculate the molecular formula using the empirical formula and molar mass

    U.4 + AS.4 - Determining the empirical and molecular formula 

    Complete worked examples in the Pearson textbook page 25 - 26
    Syllabus points addressed:
    ​U.4: The empirical and molecular formula of a compound give the simplest ratio and the actual number of atoms present in a molecule respectively.
    ​AS.4: Determination of the molecular formula of a compound from its empirical formula and molar mass.

    ​
    ​

    Content- based inquiry question

    1.2 What is the definition of the empirical and molecular formula?

    Practice what you have learned 

    Differentiation by outcome:
    All: Oxford Textbook - Quick questions: 24-35 p27
    Most: Silberberg Textbook - SL Ch 1: 6a, 13, 17b, 25, 32, 44, 46

    Biology 

    The science of Flavour 

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