Monday, September 14, 2009

TOK When are symbols necessary in aiding understanding and when are they redundant?

How often when reading a news article do we say to ourselves “Why is that relevant?”; for example why do we need to know that the woman who appeared in court for shop-theft was age 37, or even that it was a woman come to that? (Though the English language, having “he” and “she”, but no gender neutral equivalent would make this difficult - what about other languages?) If pressed a journalist would probably talk about “human interest”. The same thing however arises in science - how much information does the person reading or work require; what is relevant and what irrelevant. In the case of state symbols then certainly it is relevant if the focus is thermochemistry because changes of state (like ice melting) involve heat changes. They are also probably useful when considering equilibrium (which side of the equation has most moles of gas?) or kinetics (water in thegas phase is much more “dilute” than as a liquid) and in electrolysis (molten and aqueous sodium chloride give different products). If the focus is purely stoichiometric however then the information may be redundant,

for example C6H6 + 3 H2 C6H12

one mole of benzene, whether it is in the liquid or gas phase, will still react with three moles of hydrogen (pretty safe to assume this is a gas!). Probably the best policy is to consider that you really do not know what use an equation may be put to, and so include state symbols just to be on the safe side (as we have in this book), but whether it adds human interest to these equations is another matter!
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The IB Learner Profile

THE IB LEARNER PROFILE

Inquirers: They develop their natural curiosity. They acquire the skills necessary to conduct inquiry and research and show independence in learning. They actively enjoy learning and this love of learning will be sustained throughout their lives.

Knowledgeable: They explore concepts, ideas and issues that have local and global significance. In so doing, they acquire in-depthknowledge and develop understanding across a broad andbalanced range of disciplines.

Thinkers: They exercise initiative in applying thinking skills critically and creatively to recognize and approach complex problems, and make reasoned, ethical decisions.

Communicators: They understand and express ideas and information confidently and creatively in more than one language and in a variety of modes of communication. They work effectively and willingly in collaboration with others.

Principled: They act with integrity and honesty, with a strong sense offairness, justice and respect for the dignity of the individual, groups and communities. They take responsibility for their own actions and the consequences that accompany them.

Open-minded: They understand and appreciate their own cultures and personal histories, and are open to the perspectives, values and traditions of other individuals and communities. They are accustomed to seeking and evaluating a range of points of view, and are willing to grow from the experience.

Caring: They show empathy, compassion and respect towards theneeds and feelings of others. They have a personal commitment to service, and act to make a positivedifference to the lives of others and to the environment.

Risk-takers:They approach unfamiliar situations and uncertainty with courage and forethought, and have the independence of spirit to explore new roles, ideas and strategies. They are brave and articulate in defending their belief

Balanced: They understand the importance of intellectual, physical and emotional balance to achieve personal well-being forthemselves and others.

Reflective: They give thoughtful consideration to their own learning and experience. They are able to assess and understand their strengths and limitations in order to support their learning and personal development.