It has to be understood that 2 moles of oxygen are there in each mole of PbO2. Then it has to be calculated for 2 moles of oxygen.
Amount of oxygen = 2 * 5.43 moles = 10.86 moles Now it is also a fact that each mole of H2O contains 1 mole of oxygen. Then it can be easily concluded that 10.86 moles of water will be produced. I hope the procedure is clear enough for you to understand.
<span>Acid is a molecule capable of
donating hydrogen ion and they form aqueous solutions with a sour taste while
base is a substance that accepts proton from proton donor and in aqueous solution,
they have an astringent or bitter taste. Moreover, a good example for base is
sodium hydrogen carbonate as baking soda or baking powder and for acid, the
most common example is the acetic acid or vinegar.</span>
The Clausius-Clapeyron equation is used to estimate the vapour pressure at different temperature, once the enthalpy of vaporization and the vapor pressure at another temperature is given in the question. The detailed solution is shown in the image attached. The temperatures were converted to kelvin and the energy value was converted from kilojoule to joule since the value of the gas constant was given in unit of joule per mole per kelvin. The fact that lnx=2.303logx was also applied in the solution.