Question

Many hospitals, and some doctors\' offices, use radioisotopes for diagnosis and treatment, or in palliative care (relief of symptoms such as pain). Some radioisotopes used in medicine are listed below. Write the isotope symbol for each radioisotope. Replace the question marks with the proper integers. Replace the letter X with the proper element symbol.

a) Iodine-131:

b) Iridium-192:

c) Samarium-153:

Answer 1

a)
`^(131)_(53) I`

b)
`^(192)_(77) Ir`

c)
`^(153)_(62) Sm`

Step-by-step explanation:

The symbols of the isotopes are written like

`^(A)_(Z) X`

where,

X is the element

A is the mass number (protons + neutrons)

Z is the atomic number (protons)

a) Iodine-131

The atomic number of iodine is 53. The mass number of this isotope is 131. The symbol is
`^(131)_(53) I`.

b) Iridium-192

The atomic number of iridium is 77. The mass number of this isotope is 192. The symbol is
`^(192)_(77) Ir`.

c) Samarium-153

The atomic number of samarium is 62. The mass number of this isotope is 153. The symbol is
`^(153)_(62) Sm`.