If A represents atomic mass and Z represents atomic number, which of the following describes an atom after a proton is emitted from its nucleus?
A. A+ 1, Z + 1
B. A-1,Z-1
C. A+ 1, Z-1
D. A-1, Z + 1
My answer is B
yes
charge goes down
mass goes down
Thank you.
To answer this question, we need to understand what happens when a proton is emitted from an atom's nucleus.
When a proton is emitted, the atomic mass (A) of the atom decreases by one because a proton, which has a mass of approximately 1 atomic mass unit, is being lost.
Additionally, the atomic number (Z) of the atom decreases by one because the emission of a proton means one less proton is present in the nucleus, resulting in a change in the element.
Let's now consider the given options:
A. A+1, Z+1: This option suggests that the atomic mass increases by one and the atomic number also increases by one. This is not correct because the emission of a proton results in a decrease in both A and Z.
B. A-1, Z-1: This option correctly reflects that the atomic mass decreases by one and the atomic number also decreases by one due to the loss of a proton. Therefore, this option seems to be the correct answer.
C. A+1, Z-1: This option suggests that the atomic mass increases by one while the atomic number decreases by one. This is incorrect because, as mentioned earlier, the emission of a proton leads to a decrease in both A and Z.
D. A-1, Z+1: This option presents an increase in atomic mass by one and an increase in atomic number by one. However, as stated before, the emission of a proton causes a decrease in both A and Z.
Based on this analysis, option B (A-1, Z-1) seems to be the correct answer as it accurately reflects the changes that occur when a proton is emitted from an atom's nucleus.