Lost. Help!

Question

Which statement correctly compares nuclear fission with nuclear fusion?
A. Nuclear fission uses uranium, and nuclear fusion uses hydrogen.

B. Nuclear fission produces energy from matter, and nuclear fusion produces matter from energy.

C. Nuclear fission joins nuclei, and nuclear fusion splits them.

D. Nuclear fission produces radioactive waste, and nuclear fusion does not.

Answer 1

Hi Amanda,

 

A. Nuclear fission uses uranium, and nuclear fusion uses hydrogen.

This is not worded intelligently. Nuclear fission does not use uranium. Uranium undergoes nuclear fission. But, so also does plutonium, radium, polonium, etc. The same is true for the fusion statement. Small elements undergo fusion, and hydrogen is such an example. It undergoes fusion to create helium. Large nuclei undergo fission. So, statement A is not true because of the way it is worded and that it is not general. 

B. Nuclear fission produces energy from matter, and nuclear fusion produces matter from energy.

This is TRUE. Nuclear fission splits a large atom into smaller ones and gives off energy. Some matter Δm is lost and converted to energy by Einstein's Δm*c². Nuclear fusion takes smaller elements and makes a larger element. It takes energy to be converted to mass for fusion to occur. For instance, the mass of Helium is greater than the sum of the masses of the constituent Hydrogen atoms.

C. Nuclear fission joins nuclei, and nuclear fusion splits them.

This is wrong. Nuclear fission splits nuclei, nuclear fusion joins nuclei.

D. Nuclear fission produces radioactive waste, and nuclear fusion does not.

Both processes create radioactive waste.

 

So, the answer is B