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  • Greetings fellow nerds.

  • I’ve been asked by one of my patrons to go over the various pieces of equipment for setting up an amateur lab.

  • After thinking about it I realized i can’t possibly cover the whole thing in one video

  • because every lab is going to be different and the equipment needed for one lab might not be applicable to another lab.

  • So i’m going to split this video into a series and try and cover as much equipment as possible.

  • I’ll let you decide which ones are applicable to you.

  • In no particular order, let’s start with beakers.

  • Whenever people think of chemistry they most often think about beakers.

  • Used for handling and transferring chemicals as well as performing reactions,

  • their symbol as the defining tool of chemistry is rightly deserved.

  • Try and get an assortment of sizes for your lab and make sure the glass is a material called borosilicate glass.

  • Such glass has a low coefficient of thermal expansion and thus can withstand heat shock very well.

  • Another good thing about beakers is that you won’t confuse them with drinking glasses and possibly poison yourself.

  • Almost every serious chemistry lab has a hotplate stirrer.

  • It’s probably the number one piece of equipment youve seen me use in most of my videos.

  • As the name suggests, it behaves as a hotplate and allows you to heat up liquids.

  • But it also has a magnetic stirring function.

  • It works by having a magnet mounted on a motor underneath the hot plate.

  • The magnet couples to a magnetic stir bar through the hotplate and allows you to stir your solutions as long as you want without having to do it manually.

  • You of course need a supply of teflon coated stir bars that are chemically resistant

  • and you have to remember to retrieve them at the end of your experiments.

  • Unfortunately hotplate stirrers are ludicrously expensive.

  • The ones you see here cost hundreds of dollars each.

  • I’d say they were worth it if they were more reliable.

  • But the one you see on the left is broken and i don’t have the skill to repair it.

  • And the one on the right has had a heater element failure and a power supply failure that required replacement.

  • Neither of these hot plate stirrers lasted longer than a year.

  • So get a hot plate stirrer if you really want one, but be aware of the cost.

  • Some sort of weigh scale is absolutely essential for a laboratory.

  • In our particular universe the amount of a substance is directly proportional to its mass.

  • So measuring that is the most reliable way to know how much of something you have.

  • Now a laboratory scale like this one is very good, reliable, accurate and precise.

  • It’s also a few thousand dollars, so youre probably not going to buy one, I sure haven’t.

  • Instead, most of your needs can be served by getting two scales of different ranges.

  • The reason why a good laboratory scale is so expensive is because it has a large dynamic range.

  • It can measure a wide range of values and also count tiny increments between those values.

  • That kind of precision requires good design and high quality machining that eventually translates to very high cost.

  • Instead, by using two different scales that have different ranges,

  • you can cover most of the measurements youll ever need.

  • Chances are if youre measuring a heavy amount of substance, the small changes are inconsequential.

  • And if youre measuring a very small amount of substance, you won’t be loading the scale with a heavy container.

  • So using two different scales can be very effective and cheap.

  • Each of my scales here are only twenty dollars each.

  • The drawback of this approach if youre doing high precision analytical or semiconductor work

  • and need more dynamic range than your scale allows.

  • In those cases, using a less precise scale that can’t tell you what tiny amounts you have can seriously undermine your work.

  • Keep this in mind when selecting your scales for the type of work youre doing.

  • Fortunately, for most amateurs, the two cheap scales approach is sufficient.

  • A very useful thing to have in an amateur lab is a large supply of resealable plastic bags.

  • These are also known as ziplock bags.

  • For inorganic chemicals like salts, metals and so on, these are cheap and readily available storage.

  • A useful convenience is that they flatten or expand depending on how much they are filled unlike bottles.

  • So you can have a full bag of material and relatively unused bag and theyll only take up as much space as needed.

  • Bottles and boxes however take up the same space whether they are full or not.

  • These bags are also a useful for safely storing bottled chemicals if youre worried about leakage or vapors coming out.

  • So have a good supply of resealable plastic bags in your lab.

  • Just remember not to store organic chemicals or chemicals that dissolve plastics for obvious reasons.

  • A lab jack is one of those annoying things you don’t know you need until you need it.

  • And then you forget you need to acquire one when you don’t need it.

  • All they do is lift things to various heights.

  • While you can get away with just using anything on hand like other beakers.

  • A lab jack is so convenient and useful that i think it’s worth having one or two.

  • I primarily use these for sitting the receivers in my distillations.

  • Vials are tremendously useful for storing and running small reactions.

  • Youve seen me use them in large number of my videos.

  • Vials have replaced the famous test tube for most chemists.

  • Theyre self-standing so you don’t need a test tube rack.

  • Theyre easy to stack and store and so many industries outside of chemistry also use vials so vials are pretty easy to acquire.

  • When buying vials pay attention to their caps.

  • Foil caps are good for non-reactive solids but will be destroyed by reactive acids or strong bases and theyre not liquid proof.

  • For liquids and more reactive substances like acids, plastic liners are prefered.

  • This one is a polycone type plastic liner. Now plastic is great but even plastic is permeable to organic solvents.

  • The ultimate liner is a PTFE or teflon liners.

  • You can use these for very wide range of chemicals and theyre extremely resistant.

  • Theyre also rather expensive so keep in mind what kind of chemistry youre doing and purchase the appropriate vials.

  • Now i’m not going to cover all the types of glassware in this video as that topic is so vast it requires its own video.

  • But what i do want to show you is the current standard of using ground glass joints.

  • Now in the past chemists had to connect glassware using corks.

  • Ground glass joints are the more expensive but ultimately more convenient modern way.

  • This is because the sizes have all been standardized and most glassware will be labelled with the right type of joint.

  • This one for example is 24/40 joint meaning it has 24mm wide opening that extends 40mm down.

  • The taper is standardized to 1:10 for all glassware.

  • I can mate this joint with any other piece of glassware of the right gender

  • even if they are from completely different manufacturers thanks to the standard.

  • Now 24/40 is a common standard for moderately sized glassware and for smaller glassware there is the 14/20 standard.

  • So pay attention to the joint sizes of the glassware youre buying to make sure it’s compatible with your existing glassware.

  • That being said, having a mix of glassware is still very usable as there are adapters to fit different types of joints together.

  • This way you don’t have to purchase duplicates of every glassware part you have and you can mix and match parts for special experiments.

  • Now ground glass joints can seize up and become stuck.

  • To prevent this you first grease up the joints to both seal and lubricate them.

  • A very common grease is dow corning vacuum grease which is quite inert and in general won’t harm your reactions.

  • You can also use hardware store greases but be careful as some can react with your chemistry

  • or might decompose at the temperatures youre working with.

  • Grease is conveniently applied by first putting some in a syringe and then applying it to the joint.

  • You don’t need to cover the whole thing, just a bit on the side

  • and turn the joints when you put them together until the lubrication gives an even coat.

  • Okay that’s all the time i have for this video. There is still a lot more to cover and more videos to go.

  • In the next video i’ll probably look at things like safety gear and stuff for electrochemistry.

  • If there is any piece of lab equipment you think i should go over, let me know in the comments.

  • Thanks for watching.

  • If you would like to support the continued production of science videos like this one, please support the channel on Patreon. Links are in the video description.

Greetings fellow nerds.

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業餘實驗室的設備--第一部分 (Equipment for an amateur lab - Part 1)

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    Yrchinese 發佈於 2021 年 01 月 14 日
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