Question

which of the following could have 82 neutrons? w-182 cs-132 ba-138 ta-181

Explanation:

Step1: Recall neutron - proton relationship

Number of neutrons = Mass number - Atomic number

Step2: Find atomic numbers

W (tungsten) has atomic number 74, Cs (cesium) has atomic number 55, Ba (barium) has atomic number 56, Ta (tantalum) has atomic number 73.

Step3: Calculate neutrons for each

For W - 182: $182−74 = 108$ neutrons.
For Cs - 132: $132−55 = 77$ neutrons.
For Ba - 138: $138−56 = 82$ neutrons.
For Ta - 181: $181−73 = 108$ neutrons.

Answer:

Ba - 138