As students prepare for their exams, questions that only assessors can answer often pop into mind. Unfortunately, most students don’t have access to assessors in most of their subjects, so we took your questions and presented them to a senior VCAA assessor who has extensive experience in marking the VCE exams that you will soon sit. Here are his/her answers.

We hope that your exam preparations are going well.

TSFX.

I have looked though a few past exams on the vcaa website and I was wondering if definition questions will be asked? My teacher said it is important to memorise definitions, but I dont see it as worthwhile, considering as it will not be explicitly asked.

The definition of chemical terms is not usually asked such as ‘What does boiling point mean?’ However, if they ask ‘Explain the reason for the changes in boiling point in the homologous series of alcohols.’, you would need to know the definition of boiling point, homologous series, alcohols as well as dispersion forces, hydrogen bonding and dipole/dipole forces. Even though a ‘simple’ question of ‘Write down the definition of boiling points’ is not expected on the exam, you will need to incorporate its meaning and be capable of applying the meaning to new situations. It is critical that you can EXPLAIN not just MEMORISE each chemical concept and term used in Units 1,2,3 and 4.

Do you prefer students to answer in full sentences or in dot points? Will you lose marks if answers remain in dot points?

Answers to questions can be put into dot points. However, if you are asked to ‘Explain’ a concept or ‘Justify’ your answer, it is better for you to write it in full. Examiners have to be able to understand your answer to give you marks, so the easier you make it on them, the more likely you will receive full marks. Secondly, please DO NOT ABBREVIATE words, unless you have explained your abbreviation. If you write L.C.P. instead of Le Chatelier’s Principle WITHOUT DEFINING IT, you may not receive any marks for it.

In the last few years, VCAA is expecting students to be able to explain concepts and validate their conclusions for more questions than they have in past exams. If your dot points are not well explained, your answer will not receive full marks.

What do students lose the most marks for on an exam?

This is dependent on the year the exam was written and on the knowledge of the student. Most of the time, marks are lost by students who have not read the question completely, hence they do not answer all the parts of the question. Please read Chris Dwyer’s articles in “The Age” over the last couple of years, he provides a different perspective on what students do or don’t complete well each year. This article changes every year and the examination changes every year.

What are the rules for significant figures? Do you accept a range of answers that are close to the correct answer? Thank you.

Your final answer should have the same number of significant figures as the least number of significant figures in your data. There is a range that is available for each answer, but not a range in significant figures. Please ensure that you have the correct number of significant figures in your FINAL ANSWER. Do not round up, to the required number of significant figures until the last answer. Only your final answer needs to have the correct number of significant figures.

Will questions asked in the exam always relate to a study design dot point? Or will there be questions that may deviate from the study design and require general knowledge? Thank you.

The questions that are on the examination will relate to the study design. However, the situation that is presented may be a ‘new scenario’. So, you may be expected to think on your feet, review all the concepts that have been taught and use what you believe is applicable.

Should we always put states in equations, even if it is not asked for? Thank you.

Please provide states whenever possible. Read over the information that is provided, often they will tell you the states of each compound in the question. The only area where they will not expect states is in the organic pathways.

Are we allowed to refer to our databooks during reading time? Thank you.

You are permitted to look through the examination booklet and the Data booklet during your reading time. You are not permitted to pick up your pen and write during your reading time.

How are significant figures marked? Do you lose a mark every time you get it wrong?

Significant figures are expected all the time. Please ensure that you check the number of significant figures for EVERY QUESTION. You will lose a mark anytime your answer is not within the correct range of answers and if the correct significant values are not provided. Ensure that you use the correct significant figures always.

How strict are assessors on rounding errors? say you use an earlier rounded answer and are off by 0.1 or 0.01, will you lose marks?

Rounding incorrectly, before the end of the calculations is a BIG MISTAKE. Please ensure that you DO NOT ROUND UP/DOWN your answer UNTIL THE VERY END OF THE QUESTION. Leaving your answer to 4 or 5 significant figures is ideal during your calculations. Rounding your answer early will incur errors.

Will I lose marks if I don’t provide an answer with the appropriate significant figures? E.g. If I write 30.55 instead of 3 x 10^3? And vice versa?

Absolutely! If the information that you are provided is to 1 significant figure, then your answer must be to 1 significant value. The answer can only be as accurate (in terms of significant figures) as your original data. Hence 30.55 has 4 significant figures while 3 x 103  has only 1 significant figure.

What are some topics found in the Course work that is generally not tested on the VCAA Exam?

Awesome question! If only I knew! If only anyone knew! We do not know. Most of the topics are covered every exam. The study design is too big to include a question about every aspect but usually most of the topics are covered. The writers of the examination can pick and choose different sections or different ways of asking questions every year. Hence every year has different questions and a different focus.

For combustion equations, should the state of water be in the liquid or gaseous form?

Water should be shown as a gas, since combustion usually occurs at temperatures higher than 100o C, then water should be gaseous. However, you may write the state of water as a liquid, this is acceptable.

If there’s a percentage number in a question, and is has the lowest significant figures, does our final calculation have to be based on the significant figures of the percentage? Or does the percentage not affect our significant figures answer?

In general, the significant figures that count are of the measured quantities such as mass/concentration/number of mole. If the percentage is related to the mass of a compound or element in the ore it will be important. It is important to read the question carefully, will you need this percentage to complete a calculation? Is this percentage providing you with important data to complete the question? If yes, then the significant figures of the percentage will need to be taken into account.

Does it matter which monosaccharide loses the H and O atom when glycosidic links are formed? If yes, how do we determine this?

It does not matter which O and H is lost or left as each OH on both sides of the monosaccharide are identical. The examination will not ask you which oxygen or hydrogen from the OH groups is kept or lost.

How do we determine the change in oxidation number of an element, when two of the same element in different molecules are formed in the products. FOR EXAMPLE: oxygen in the equation:: CH3CH2O + O2 —-> CO2 +H2O

In this case, you will notice that in the reactants we have O2 (g) which is in its natural state, so it’s oxidation number will be zero while in both products the oxidation number of oxygen is -2 (CO2 oxygen is -2×2=-4 while carbon will be +4, while in H2O, Hydrogen is +1×2 =+2, hence Oxygen is -2). Hence this will be a redox reaction where oxygen (from oxygen gas changes from 0 to -2) is the oxidant.

Therefore, you will need to check the oxidation number of the ‘same element’ in all of the reactants and products to determine if a redox reaction has occurred and which element/compound has undergone oxidation or reduction.

Hi there! Do you penalise students for taking up more space than the lines on an exam paper? I have big handwriting and sometimes I can be pretty inarticulate, so I usually end up taking up more space than is given, sometimes going into the margins. Is this just annoying or is it something I can lose marks for? Thank you!

Hi! You are asked not to write in the margins, this is clearly written on the examination paper. If you run out of space please write a note under the question to say where the rest of your answer has been written. As the papers are scanned and split up into each separate question, it is critical that you specify where we can find the rest of your answer.

Hi, what are the best (most accurate in terms of difficulty) practice exams to do for Chemistry? Which of the trial companies is most suitable (Neap, LisaChem, STAV, Insight, TSSM)?

A better question is, how many trial exams do you have time to complete? Each of the above companies produce some good trial exams and they provide a variety of the types of questions you could find on the upcoming examination. In general, Neap and STAV, tend to be the most difficult exams to complete. However, I would recommend you complete a number of papers from different trial companies, as they will give you a better range of questions to practice.

What is the main factor that results in the GI levels of certain foods? Is it the presence or absence of carbohydrates in the food, or the specific carbohydrate that is in the food (e.g. amylose vs amylopectin ratio)? Thanks.

The GI is a ranking of carbohydrate foods from 0 to 100 based on how quickly and how much they raise blood sugar levels after being eaten. This is related to how quickly a carbohydrate containing food is broken down into glucose. Low GI foods produce a slower, lower rise in blood sugar levels.

Firstly, GI definition is important (as stated above), secondly the ratio of Amylose and Amylopectin will influence the GI levels of foods. Both the definition of GI, the difference between the two different starches and the ratio of the two different starches in food is important.