The phrase “molar mass of sn02” is interpreted as the molar mass of tin(IV) oxide, SnO2, where the symbol for oxygen is the letter O (not the numeral 0). The molar mass is the sum of the atomic masses in the formula, expressed in g/mol.
Chemical formula and meaning of subscripts
SnO2 contains one tin atom (Sn) and two oxygen atoms (O). The subscript 2 multiplies oxygen’s atomic mass by 2. Tin(IV) oxide is consistent with oxidation states Sn4+ and O2−, giving a neutral compound.
Atomic masses used
| Element | Symbol | Count in SnO2 | Atomic mass (g/mol) | Contribution (g/mol) |
|---|---|---|---|---|
| Tin | Sn | 1 | 118.71 | 118.71 |
| Oxygen | O | 2 | 15.999 | 31.998 |
Molar mass calculation
\[ M(\mathrm{SnO_2}) = M(\mathrm{Sn}) + 2 \times M(\mathrm{O}) \] \[ M(\mathrm{SnO_2}) = 118.71 + 2 \times 15.999 = 118.71 + 31.998 = 150.708\ \mathrm{g/mol} \]
Rounded to typical periodic-table precision, the molar mass of SnO2 is 150.71 g/mol. The same numeric value is the formula mass in atomic mass units (amu) because \(1\ \mathrm{amu}\) per particle corresponds to \(1\ \mathrm{g/mol}\) per mole.
Mass contribution picture
Common rounding conventions
Periodic tables often list oxygen as 16.00 and tin as 118.71. Substituting \(16.00\) for \(15.999\) gives \(118.71 + 2 \times 16.00 = 150.71\ \mathrm{g/mol}\), matching the rounded value.