Answer:
a) 
b) 
c) 
Explanation:
The symbols of the isotopes are written like

where,
X is the element
A is the mass number (protons + neutrons)
Z is the atomic number (protons)
<em>a) Iodine-131</em>
The atomic number of iodine is 53. The mass number of this isotope is 131. The symbol is
.
<em>b) Iridium-192</em>
The atomic number of iridium is 77. The mass number of this isotope is 192. The symbol is
.
<em>c) Samarium-153</em>
The atomic number of samarium is 62. The mass number of this isotope is 153. The symbol is
.
Convert the mass to moles .
85.1 g ÷ 20.18 g/mol = 4.21704658
convert the moles to molecules
4.2170 mol × 6.022^23 molecules/mol = 2.539^24
Answer:
A solvent is a substance which dissolves a solute. When a solvent dissolves into a solute, it creates a solution