Last questions I'll ask, I got the rest the rest :) And a quick thank you to Bob, you've helped me out a lot and even taught me some stuff I couldn't learn from school. You're amazing.

Question

17 Which statement about the number of protons and neutrons in a nuclear change is correct?(1 point)

The relative numbers of protons and neutrons are the same before and after the change.

The total atomic mass before and after the change remains the same, but the total charge is different.

The total charge before and after the change remains the same, but the total atomic mass is different.

The relative numbers of protons and neutrons can differ before and after the change, but the total number of those particles remains the same.****

(If not D then C)

19 A nucleus decays to produce a nucleus with one additional proton. Which type of decay did the nucleus undergo?(1 point)

gamma decay

alpha decay

beta-minus decay****

beta-plus decay
(if not C then D)

20 Which type of decay is a form of nuclear fission?(1 point)

gamma decay

beta-minus decay****

alpha decay

beta-plus decay
(Pretty confident on this but still want to double check)

Answer 1

17.
I'm not sure how the term "relative number of protons and neutrons" is being used but I agree with your choice. I think C, your other possible choice definitely is not right.

19. Let's work this out logically.
92U238 ==> 93Np238 + -1e0
So if we start with 92U238 it goes to produce an element with "one additional proton" that means that element must be 93. that makes it Np238 and to make everthing add up on both sides we know that particle that was emitted has to have a -1 charge and a zero mass. That's a beta minus particle. You don't need to guess. See what happens IF 92U238 gives off a beta plus.
92U238 ==> 1e0 + 91Pa238 BUT this can't be right because it produced an element "with one LESS" .........
20.
I don't know what "a form of nuclear fission" means but I'll try to guess.
First, I don't agree with your choice.
Nuclear fission to me means you "split" an atom apart producing smaller pieces. You saw in question 19 that beta minus INCREASES the atomic number by 1. In my example of beta + I showed you that beta plus produces an element with 1 less proton which is a SMALLER number. I think that is whar "form of nuclear fission" must mean. I also think, if my understanding of "form of nuclear fission" is correct. is that alpha decay will qualify. For example:
92U238 ==> 2He4 + 90Th234
Personally I don't like that expression of "form of nuclear fission". We can't answer a question we don't understand.
Thanks for the compliment. I've been teaching for 74 years. Good luck. Be sure and let me know if I inadvertently make a mistake. Sometimes I read the quesion wrong or interpret it wrong. My eyesight is getting worse by the day, too, and that sometimes is a problem.