Which of the following processes are spontaneous: (a) the melting...

Question

Which of the following processes are spontaneous: (a) the melting of ice cubes at -10 °C and 1 atm pressure; (b) separating a mixture of N2 and O2 into two separate samples, one that is pure N2 and one that is pure O2; (c) alignment of iron filings in a magnetic field; (d) the reaction of hydrogen gas with oxygen gas to form water vapor at room temperature; (e) the dissolution of HCl(g) in water to form concentrated hydrochloric acid?

Accepted Answer

Hey everyone. So here it says, identify the phase change description that corresponds to a positive DELTA G. Remember if your delta G. Is positive, that means it's non spontaneous, meaning it doesn't occur under natural conditions. So here ice forming liquid water at a standard pressure and 4°C. Right? So ice solid ice going to liquid water. Remember water begins to melt once we get to 0°C and it starts climbing. So it makes sense that we would be going from ice to liquid water with a temperature of 4°C. So this would be spontaneous and therefore delta U. Will be negative, not positive. Next steam forming liquid water at standard pressure 150°C. Remember water starts to vaporize once we get to 100°C the temperature is even higher than that. So we should expect our water to stay in its gaseous phase. We won't expect steam to condense down into a liquid. This doesn't make sense. This does not occur naturally. Therefore it's non spontaneous and delta G will be positive. This would be our answer. So far, Liquid water forming steam at standard pressure 106°C. Here, the temperature is high enough that liquid water can be vaporized into gas. So this isn't um spontaneous And then liquid water forming ice at a standard pressure and negative 5°C. So the temperature is low enough that liquid water can solidify into ice. So this is possible here are answer would have to be option

Watch next