To find the number of neutrons, we need to subtract the atomic number from the mass number.
Number of neutrons = mass number - atomic number
Number of neutrons = 226 - 88
Number of neutrons = 138
Therefore, an atom of radium has 138 neutrons.
Answer: D. 138
The element radium has a mass number of 226 and an atomic number of 88. How many neutrons does an atom of radium have?
A. 226
B. 314
C. 88
D. 138
1 answer
1 answer