@EmAugus
“vant Hoff” factor is just a fancy way of saying “how many ions it makes in water”. All other things being constant, the compound that makes more ions in water will raise the boiling point more, so that automatically eliminates both choices with KCl. Now the other thing that affects how boiling point is raised is concentration, specifically molality. Now, they don’t give you molality, but you know that it’s directly related to molarity (the big M), so you know that the greater molarity has the greater boiling point elevation. Ergo, choice 4.
Yes, the answer to the radiation question is gamma rays. They’re highly penetrating and what gives it away is that the passage mentions that the emission isn’t deflected by a charged field. This tells you that it’s neutral, and the only neutral particles (at least on the Regents) are gamma rays and neutrons, but neutrons are heavy and don’t penetrate well, so that just leaves gamma rays.
@IequalSmart
Believe it or not, fission is less correct than radioactive decay. I believe the original question asked what is the name for the reaction that emits alpha and beta particles. Fission never emits those particles, only neutrons come out. Radioactive decay is accurate, although I don’t know if it would be accepted since I believe the original question mentioned “alpha and beta decay”. It’s anybody’s guess though. The correct answer was “natural transmutation” though.
@HritikKumar
The answer is density. Hopefully you were able to eliminate temperature based on the fact that it was cooled. Mass will stay the same because moles aren’t affected at all since it’s a sealed container. Volume actually decreases since the particles have less energy to go far. And once you know that volume decreases and mass stays the same, hopefully you could figure out that that would mean that density would have to go up. Otherwise you could have used process of elimination or, my preferred method, visualizing the gas contract as it cools.
@MrBryan
Yes, chem does have one of the toughest curves. I think it hurts you (your scale score as a % is lower than your raw score as a %) until you get into the low '70s and under.
@Keyboard1528 I didn’t remember if fission would be correct, but i was pretty sure they wouldn’t accept radioactive decay, as that contains many other decay modes. Anyone know if they accepted radioactive decay?
@IequalSmart
You’re right about that, radioactive decay is the umbrella term that describes alpha, beta, and other kinds of decay, but the same logic applies to natural transmutation, which is the answer. The problem, I think, with radioactive decay is that “natural transmutation” is the term preferred by the Regents in the context of reactions, not radioactive decay, plus the fact that decay may have been mentioned in the question. Then again, I’ve seen some pretty lenient answer possibilities for questions on this regents. At the end of the day, it’s anybody’s guess what they would/wouldn’t give credit for, and none of us will know the answer to that until they release the answer key.
@ Keyboard1528 Yeah I got density
For the spectrum question, one of the questions were about how the spectroscope helps see colors?
I wrote:
It shoots out lines that corresponds to the metal ions.
Is this considered to be correct?
@alexhuang76
I think you’d have to mention how electrons emit energy when they return to the ground state in order to earn credit for that one. But they may give you credit, I don’t know.
Not hat was the other question, the question after that
Sadly I got a 96. It’s weird because I only knew that I got the last one wrong. Apparently they accepted radioactive decay, so I guess I’ll be vague when I’m not sure from now on.
@alexhuang76
Oh, my mistake. I’m not a grader so I don’t know what they’d accept, but if you mentioned comparing metal spectra to those of the unknown I think you’d get credit.
I got a 92 when I took it last year:b 80/85 which would probably be a 96 on other science regents.
Just got my score got a 98 only 2 more points and I would have had the highly desired 100