PH=14-pOH
pOH=-lg[OH⁻]
pH=14+lg[OH⁻]
pH=14+lg(8.7*10⁻¹²)=14-11.06=2,94
<span>As mentioned, the isomerization of cyclopropane to propylene is a first-order process with a half-life of 19 min at 500°c. A first-order reaction kinetic rates means that the rate is constant throughout the reaction.
Thus, the time it takes for the partial pressure of cyclopropane to decrease from 1 atm to 0.125 atm at 500°c is </span><span>57 minutes.</span>
As you mentioned the question in chemistry so it may be a concentration unit I.e mass per volume.
(SOLUTION)
Mass/volume = total mass/ total volume
Now:
Total mass= 42.95 g
Total volume =351.8mL
Put these values in above equation;
Mass/volume = 42.95/351
“”. = 0.122 g/mL