Seriously, how can you read this tripe without wanting to hit your head against a wall? How can you call a novel that has this sort of nonsense and does almost every single chemistry equation wrong "hard science fiction"? Does anything that spouts pseudoscientific BS qualify as "hard science fiction" these days?
IMHO you are being too hard on the book. In the book, the things Watney does are plausible solutions to problems that make sense to me.
Andy Weir said he didn't want Watney being "hit by lightning" over and over. The initial chain of events that leads to Watney being stranded is implausible (and Andy Weir is the first to admit that the physics is wrong there, because the atmosphere of Mars is so thin). But once Watney is stranded, the rest of it makes sense to me.
This isn't like a story where someone needs to "restart the sun" by flying a ship made of "Unobtanium" into the sun and lighting off nuclear bombs. If you fix the science mistakes in a story like that, there is no story left; it's just fundamentally wrong.
In an interview, Andy Weir mentioned getting feedback from some chemist, and he said something like "I loved that, because chemistry is what I'm worst at". It sounds like you are so expert at the chemistry stuff that every mistake was a torment for you, and I think I get it... I can picture how annoyed I would be if the book was about software development, and lots of little stuff was constantly wrong.
One of his mistakes: someone actually calculated how much the Hab would heat up from burning up the rocket fuel to make water, and concluded that if Watney burned the fuel as fast as described, the Hab would heat up to 400 degrees C. But that mistake doesn't ruin the book for me, because we can assume that he just didn't burn the fuel as fast, or he arranged some sort of heatsink or something to get rid of the heat. Fundamentally, you can make water by burning hydrazine in the presence of oxygen, so it works for me.
I also liked the way he portrayed NASA. On the one hand, everything NASA does is expensive and takes forever, but on the other hand, his equipment works and he trusts it; and there was one launch that failed, and Weir listed two places where NASA procedures would have prevented the failure if there had been more time. (Someone would have studied the effects of a "shimmy" on protein cubes, and also someone would have found a minor defect in a bolt and replaced it with a perfect one; either of these would have prevented the failure.)
A novel that I hated, that I just couldn't get through, is The Windup Girl. I bought it figuring "anything that wins both the Hugo and the Nebula must be worth reading" but I hated it. I couldn't swallow the science upon which the whole plot rests. It's the future, and the worst predictions of catastrophic anthropogenic global warming came to pass: the sea levels have risen, temperatures are high, lots of people died off. As a result, fossil fuels are no longer used by anyone, and the world is in a horrible depression. So, you might think that nuclear power, solar power, and Internet telecommuting would be a big deal? Nope, cities are lighted with methane gas lamps, and the methane is made from animal feces, and moving things are powered by kinetic energy stored in "kink-springs" and the springs are wound by elephant-sized bioengineered animals. No buildings seem to have solar panels on them, and at one point the protagonist uses a computer powered by a treadle! The Internet barely seems important, which is hard to believe given that the Internet is already hugely important... but in this future catastrophe world it now takes months for a business executive to travel from America to Thailand (he has to travel by wind-powered ship), yet they still send the executive instead of using teleconferencing.
I hated The Windup Girl as much as you seem to have hated The Martian. So I guess I understand how you feel about The Martian, but I don't feel the same way.
I think the difference for me is that The Windup Girl feels like the author worked backward from his desired goals: "biopunk" is cool, so let's explain why everything is biopunk now; I want to have big factories full of elepant-sized animals walking in circles to wind "kink-springs". Whereas The Martian feels like one situation flows to another. And in fact in an interview he said that this is how he wrote the book: after he had Watney do something, he thought about what would likely happen next, and worked from there.
P.S. In the book, Watney joked about poking a hole in his glove and flying around in space like Iron Man, and they discussed just how stupid and unworkable that idea was... even Watney didn't think it would work. I gather that the movie changed this part quite a bit.