Physics Questions

[0621]

Could you please explain the answers to these 2 questions to me or tell me what site to visit that would explain it? thanks!

 

 

A positron orbiting an antiproton would make up an atom of?

 

A. unobtaninium

B. anti-hydrogen

C. positronium

D. anti-helium

 

Compared to the energy it takes to separate oxygen and hydrogen from water, the amount of energy given off when they recombine is?

 

A. much more

B. slightly more

C. the same

D. slightly less

E. much less

[toastywombel]

Could you please explain the answers to these 2 questions to me or tell me what site to visit that would explain it? thanks!

 

 

A positron orbiting an antiproton would make up an atom of?

 

A. unobtaninium

B. anti-hydrogen

C. positronium

D. anti-helium

 

Compared to the energy it takes to separate oxygen and hydrogen from water, the amount of energy given off when they recombine is?

 

A. much more

B. slightly more

C. the same

D. slightly less

E. much less

 

Number 1 the answer is 'B'. This is because a positron is the anti-particle to an electron. And an anti-proton is obviously the anti-particle to the proton. One electron orbiting on proton is hydrogen. Therefore one positron orbiting an anti-proton is anti-hydrogen. You can look it up on wikipedia's page for anti-hydrogen here. In the first paragraph you might notice that the definition for anti-hydrogen is the same as the question.

 

"Antihydrogen is the antimatter counterpart of hydrogen. Whereas the common hydrogen atom is composed of an electron and proton, the antihydrogen atom is made up of a positron and antiproton."

 

I hope this helps!

 

Number 2 I think the answer would be 'A'. I might be wrong, but I thought generally fusion reactions release a lot more energy than fission reactions.

Edited January 8, 2010 by toastywombel
Elaborating on my lazy first answer :/

[timo]

"Fusion" usually means "nuclear fusion", not chemical bonding as in Q2. But even in nuclear fusion energy is conserved.

[0621]

thanks for your help

[swansont]

multiple choice typically means homework, and it's not our mission to just give out the answers

[swaha]

for question no. 2 shouldnt it be C? if it was a solid there could be lattice energy release but for liquids?

[swaha]

pls explain.

[swansont]

The discussion is for a single molecule. The answer is indeed c. Energy is conserved.

[swaha]

thanks i got confused..........