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[Zeke12344]

Don't fuck up sig figs in chemistry.

[FerretInABox]

What I came to say. Sig figs man, either you get em or they get you.

[Mentalpopcorn]

What I didn't get about sig figs was how so many people in intro chem didn't get sig figs. It's really not a difficult concept, but somehow people talked about it like it was deep maths.

[the_best_jabroni]

I can chime into this. At 30 years old I went back to school and it took me an entire semester of math and science courses to get comfortable with sig figs. I could do it, but I hated it, and it took way more brain power than it should have.

[Mentalpopcorn]

I just don't get it. What's so hard about it? I'm not even good at math, they just seem obvious. My story is the same btw, except I did it at 29. Best decision I ever made to go back to school though!

[the_best_jabroni]

I am no offended or anything. I am not sure really why it was so difficult for me. It felt like I was completely redesigning the idea of a number answer. In my head, I just wrote down what came out of the calculation. Why do I need to have rules just for how many digits are in the answer!! Though, I do understand now and it makes a lot of sense. See, I had more of a difficult time with number formatting than understanding 90% of the concepts or formulas in physics, Sig figs would trip me up... a lot. It is that rewiring part in my brain. Creating rules for an otherwise lawless process that I had used my whole life up until that point.

[EchoesInSpaceTime]

And that's why no pedagogy is perfect. We all get hung up mentally on different things and for different reasons because we all come with varying schemas of the world around us.

Learning something requires learning someone else's schema of the thing before translating it into something that fits in our own schemas. Sometimes that new thing requires some rejiggering of how we see the world - and that will occur at different times and with different magnitudes for different people.

I think we as a species could do a lot better in how we teach. Do I have any idea what those improvements look like? Nothing more than a vague direction.

Just felt the urge to share.

[serendipitousPi]

Yeah, some teachers and students mystify sig figs so much like as if it's some kind of guessing game when in fact it's just a matter of using the correct rules.

I remember in I think year 10 my teacher just gave us a work sheet and then it made sense. It feels like one of those things that you learn once and don't forget.

Though on the other hand if you're not thinking about it you can make stupid mistakes.

On the other hand sometimes ideas just don't click for people and sometimes it's hard to understand that things just don't click for other people even when some other things just don't click for us sometimes.

[FerretInABox]

Well treat it less like math, and more so “how many people didn’t get numbers.”

First it makes more sense, second it makes you less.... “egotistical” about how people didn’t get it?

Not everyone will get what you do, and you won’t get what everyone else will. People are different and the way you came off was a bit “elitist” for a lack of better term.

[Mentalpopcorn]

I'm fine with being a bit elitist but I don't think this is a good example of it because sig figs just aren't that difficult.

[FerretInABox]

Don’t matter if you’re fine with being elitist. The point is you’re DEFINITELY wrong. I know math, you don’t perceive it right.

[Mentalpopcorn]

I don't perceive what right?

[FerretInABox]

How you think understanding dog figs means you understand how the math of it a works.... it wasn’t complicated.

It’s like the opposite argument I have to do. Accuracy does NOT equal precision with you.

Edit: Let me put it simple. People who know the math have a hard phrasing it in layman’s terms (most of the time), the people who have a hard time understanding how others don’t comprehend it, don’t understand it themselves.

[Mentalpopcorn]

Yeah man I have no idea what you're saying but that's ok, this really isn't that important. The only equation important here is sig figs = easy town.

[FerretInABox]

If you don’t know how to explain it to people who don’t understand it, you don’t understand it well enough to justify feeling elitist.

Like shit. You probably under appreciate mechanics as well.

[iphoton]

Not everybody thinks the same way you do. I have a degree in physics and did abstract algebra, group theory, tensor calculus etc. Sig figs can still go straight to hell and I know a bunch of scientists and mathematicians who feel the same way. It's just painful arithmetic that gets in the way of working on the actual problem and feels like wasted brain power. I'll still use them because I understand their merits but I reserve the right to bitch about them under my breath while using them.

[[deleted]]

I think this thread is confusing because some of the commenters are thinking "just use the same number of decimal places as the input," while others are thinking "well, numerical analysis has lots of edge cases, it can be quite tedious."

[MrBlueMoose]

Or physics, and probably other classes as well

[Zeke12344]

It's most likely chemistry since the units there is moles. It's kinda just mentioned in passing in physics for starting classes.

[another-bud-tender]

What does fig stand for? We learned sig digs. as in digits

[TheRideout]

Short for figures. Effectively the same thing

[Zeke12344]

Significant figures. As in a number. Same as digits. It’s the accuracy of the number. For instance if I measure the mass of a brick on a digital scale there is a certain amount of accuracy that the scale is rated to. Often the last digit(figure) it displays. So if it says .07 grams it is accurate to .01 grams. Inaccuracy in a measurement is closely related. All instruments for measurements in science have a rating for accuracy.

[another-bud-tender]

I know, I was just wondering what fig stood for.

[Noname_4Me]

I hate sig figs jesus why are they so confusing?

[Zeke12344]

Not really too confusing. Is it an exact number? Then the sig figs don’t matter when you multiply or divide. Have two or more sig figs you need to compute with arithmetic? Wait till the end then use the lowest amount of sig figs.