It's a possibility that your car may not start correctly.
If you are talking about bar soap, then supposedly it will form a sticky solid.
When they mix, they form an oxygen gas.
It separates and doesn't mix together. The soap sits at the top of the soft water. Soft water doesn't have that much minerals in it so it doesn't mix with the soap.
many things can happen
take a spray bottle and mix it with water and some soap and spray that were you think that you might have a leak and if the soap starts to bubble you have a leak there.
Soap does mix with food colouring and in stains.
what happens when you mix bleach and muriatic acid
You have a mess.
it makes bubbles
You will get anti-bacterial soap in the end really. Hand sanitizer will kill bacteria, and soap will wash off dirt and oils
You produce a lot of gas (CO2).
you can but then you'd get hand soap
Nothing because krypton is an inert/noble gas.