Ok, first off. I'm biased cause I took it all the way to Uni and taught chemistry.
To say that O Level Chemistry is totally the real senario in the real world would be naive, but to say that its a ONE BIG LIE means your senior have not learnt to link "past knowledge" (Secondary) with the "new knowledge" (i.e. JC), or his teacher has failed to link it for him.
The problem in the pursuit of getting grades and just passing the next exam, secondary students are drilled on certain rules that sometimes they are not told/don't care that there are exceptions (e.g the octet structure and many more).
Secondary school science is general and lays the foundation. You will encounter many exceptions to the general rules in your post secondary school. That doesn't totally negate what you learn in secondary school.
Just like composition in photography, sometimes you need to be familar with the rules before you know when to break it.
Is your senior in JC? Tell you senior that Uni would show that JC chemistry to be a lie also. But it that is really so, consider why it is that we can't skip Sec/JC chemistry and go straight away into Uni level of chemistry? Don't take foundation for granted.
