Can you explain why hot water freezes faster than a tap water?

In general, it doesn't. That's an old wives' tale.

However, under very specific orchestrated conditions, you can get it to do that by arranging things so that most of the hot water escapes as vapor, so that there is significantly less liquid water remaining in the hot cup to freeze than in the cold cup. A lot less mass to freeze, so it freezes faster.

Are you aware that you need to drain the junk out of your hot water heater yearly, so the sludge doesn't build up and ruin the heater? That sludge precipitated out of the water, makes the water cleaner. Or, from the other side, the stuff being carried by the water not treated in the water heater acts as anti-freeze.

if this is true, it might have to do with the speed with which the heat is removed. Kind of like a wind chill effect. Since there is a greater distance between hot water and freezing temperature than cold water and freezing temeprature.

I don t know just a guess.

no thats called the inexplainable point in physics