one isotope of chromium (atomic number 24) has an atomic mass of 53 amu. how many neutrons are in this particular isotope of chromium?
A. 24
B. 29
C. 53
D. 77
I say A
#protons + #neutrons = mass #.
I don't agree with A as the answer.
Look at the equation I gave you. # protons is the atomic number. That's 24. Mass # in the problem is 53.
# neutrons = 53-24 = ?
got it now B
To find the number of neutrons in an atom, we subtract the atomic number (which represents the number of protons) from the atomic mass.
In this case, the atomic number of chromium is 24 (given in the question). The atomic mass of the isotope is 53 amu (also given in the question).
To find the number of neutrons, we subtract the atomic number (24) from the atomic mass (53).
53 amu - 24 = 29
Therefore, the correct answer is B. There are 29 neutrons in this particular isotope of chromium.