Liquid Nitrogen in the Lab

A thermos with some bubbling liquid nitrogen at the bottom.
A thermos with some bubbling liquid nitrogen at the bottom.

Liquid nitrogen is used pretty much everyday by someone in my lab.

Liquid nitrogen is an extremely cold liquid coming in at close to -200°C (-330°F).

Nitrogen’s natural phase is a gas. Its a fairly common gas to, making up 78% of the Earth’s air.

When it nitrogen is condensed as a liquid it is essentially always at boiling temperature.

I tried to capture the vapor coming off the bubbling liquid nitrogen in the picture above, but its difficult to convey what liquid nitrogen is like in a photo.

Liquid nitrogen looks exactly like boiling water. If you put liquid nitrogen into a pot it would look just like a boiling pot of water ready for spaghetti to be added.

But liquid nitrogen is not boiling water. It won’t scald your hand if you touch it.

Liquid nitrogen is the coldest thing you will ever touch and can instantly freeze burn your hand.

Even things that come out of liquid nitrogen are painful to touch with you hands. I can’t do it for more than a second.

Using gloves to handle liquid nitrogen has another problem attached to it.

When you wear gloves a natural layer of sweat and oil occurs between your hand and the inside of the glove.

If your gloved hand is in the liquid nitrogen for too long, the sweat freezes.

That’s just ice though. It’s happened to me plenty of times. I just yank my hand out of the nitrogen and my bodyheat melts the ice back into sweat right away.

So if its so dangerous, why do we use it in the lab?

Liquid nitrogen is useful because it stops all biological activity. That’s why its dangerous and why its useful at the same time.

When working with a dead specimen its best to prevent bacterial decay. Bacteria can’t survive at liquid nitrogen temperatures, so its used for that.

Liquid nitrogen is also used to isolate RNA from a specimen.

Every cell has RNA inside of it, but RNA is also what many viruses are made out of.

Cells quickly learn to distinguish RNA inside the cell as good and RNA outside of the cell as bad virus RNA.

Cells have defense mechanisms to destroy RNA called RNases.

RNases can’t work at liquid nitrogen temperatures though!

I was using liquid nitrogen for a third purpose today, just to quickly freeze some worms.

More on why I need to freeze worms another day!

-Mister Ed

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Hearthstone Economy

The different items you can have in Hearthstone: cards, packs, gold, and dust.
The different items you can have in Hearthstone: cards, packs, gold, and dust.

I wanted to talk a little bit about the different types of currency in Hearthstone.

All the forms of currency are essentially funneled into getting more cards.

The first currency the game introduces is gold.

Gold is essentially interchangeable with real world money. Both can be used to purchase card packs or arena tickets.

Arena is a game mode similar to gambling. You create a deck and then try to win as many games as you can before you accumulate 3 losses with that deck.

After finishing an arena run, the game awards you a pack and a few other things as seen in the picture above.

Gold and real world currencies can only be used to buy packs for 100 gold ($1.50) each or arena tickets for 150 gold ($1.99) each.

Each pack contains 5 cards. Cards come in 4 degrees of rarity, common, rare, epic, and legendary.

The average pack has 4 commons and 1 rare. The card won from the arena run pictured above is a common card.

Unlike other CCGs there is no way to trade your cards with other players in Hearthstone.

Instead, cards must be traded with the computer at a bad exchange rate.

Card exchange is mediated through the dust currency I mentioned earlier.

The exchange rate is pretty bad as shown in this table. It takes 8 dusted common cards to get 1 common card that you want. 5 rares to make 1 rare. 4 epics or legendaries to make another epic or legendary.

Rarity Crafting

Cost

Disenchanting

Refund

Common (White) 40 5
Rare (Blue) 100 20
Epic (Purple) 400 100
Legendary (Orange) 1600 400

A pack is worth 100 gold and that sets up the exchange rate for other things in the game. The value of an arena run is always compared to what you would get if the 150 gold cost for the arena run had been spent on a pack instead.At one point I wondered what the exchange rate between dust and gold should be.

So an average 100 gold pack gets you 4 commons and 1 rare. The above table shows that the average pack is worth 40 dust.

I’d say that number is slightly higher as occasionally more rares show up and epics and legendaries can pop up as well.

I’d estimate the value of a pack to be at 50 dust. So the exchange rate is 1 dust = 2 gold.

So if you’re new to playing and are disappointed when an arena run give dust instead of gold like I was, don’t be that way.

Dust is a good thing! At least in Hearthstone.

-Mister Ed