Tuesday, March 05, 2024

Cooking up some colloids

This morning we made a couple of gallons of chocolate milk for the youth to consume after their temple trip this evening. Evidently buying milk at Costco (because it's much cheaper there than other places) and some Nesquik powder is more cost effective than buying ready-made gallons of chocolate milk. It just requires a little bit of preparation. 

So Andrew had Miriam dump a gallon of milk into a big mixing bowl and add 262 grams of powder (equivalent to 1 cup or so) and give it a few rounds with the immersion blender before pouring it back into the milk jug. This last step required Andrew's assistance because a gallon of chocolate milk sloshing around in a bowl was a little heavy and precarious for Miriam or I to handle.

(I, like, tweaked my back the other day. I could hardly move at all yesterday—was on the brink of tears for most of the day because it was so painful—but woke up feeling a bit better this morning...but not able to handle a sloshing gallon of chocolate milk).

Andrew poured the milk while I held the funnel. 

"I dunno," I said as I observed how full the jug was getting and how much milk was still left to pour in it. "Does the volume of milk increase when you add the powder?"

"Nah," Andrew said. "It just dissolves."

"Sure," I said. "But...does it though? Like, it just doesn't seem like this jug is going to hold all of this..."

"But if it dissolves then it doesn't add to the volume, right?"

"Are you sure about that? I just still don't think it's going fit..."

"Oh, it'll fit," he said confidently, dumping the rest of the milk into the funnel. 

Meanwhile, you should know that all this time Phoebe was begging for a cup of milk (for which she was repeatedly told "no"; and you should also know that she's having a really hard day because Rachel also made cookies last night and told Phoebe she couldn't have any until (and if)* they brought home leftovers and Daddy's office has a few little boxes of cookies he picked up at the store and she can't have any of those, either, and it's all just very unfair).

But the rest of that milk did not go into the jug. It swirled down the funnel and then overflowed the jug, cascading down the sides, running through my fingers, flooding the counter.

"Huh," Andrew said. "It's not going to fit."

"Shoulda just given Phoebe a cup," I said. 

"Now we know," he said. 

And then he and Miriam whipped up another batch, this time giving Phoebe a cupful before dumping it back into the jug. It worked out splendidly!

As it turns out, "a solute almost always changes the volume of the final solution." It either increases or decreases (depending on how things are mingling and what the end solution is—for example, if you mix baking powder and vinegar...the final solution might have less volume than what you started out with because there's a byproduct, right...? disclaimer: I'm not a chemist so this might not be the best example). Also, while sugar dissolves in liquids, chocolate doesn't, not really. So chocolate milk is more of a colloidal mixture rather than a solution (sometimes you have to shake things back up again to have the particles evenly dispersed because they'll separate back out on their own).

* Don't tell Rachel, but when I was packing up all her cookies last night I set aside a little container for the little kids to eat while the big kids are off having fun. So they won't even have to wait for leftovers. 

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