Answer:
30
Step-by-step explanation:
To find out the neutron number of an element we must first know what the mass value of that element is and the value of the atom number of that element. To find out these values, just look for the element in the periodic table. Once discovered simply subtract the values using the formula:
No. of neutrons = mass - atom number.
In the case of Cr, the mass is 54, while the atom number is 24. So we can find the number of neutrons.
Cr Neutrons = 54-24 = 30