No, the battery will be overcharged and battery damage will occur if it is done.
No, it will overcharge the 6 volt battery.
No it will not work
No, you cannot charge an 8 volt battery with a 6 volt charger. The voltage of the charger must match the voltage of the battery.
It is not recommended to charge a 6 volt battery with a 12 volt battery charger as it can damage the battery. The higher voltage can overcharge the battery and cause it to overheat. It is important to use the correct charger with the matching voltage to prevent damage to the battery.
If you are asking the question, can you charge a 6 volt battery with a 12 volt charger, the answer is no.
Nope.
This is not advised! The 9-volt charger might have a current limiter so that nothing burns up, but it any case if left on it will destroy the 6 volt battery by overcharging. A 6-volt charger is not expensive.
Some have a switch for 6 or 12V - if not you will "cook" a 6 volt battery using a 12 Volt charger
Yes as long as it is the right voltage: a 6v battery needs a 6v charger; a 12v battery needs a 12v charger. <><><> If you can set the battery charger's output to give either a 6 or a 12 volt output, then you must always remember to set it to 6 volts if you want to use it to charge a 6 volt motorcycle car battery.
No.
If you have two 6 volt batteries you can take a jumper wire and connect the negative post on one battery to the positive post on the other battery then connect the remaining pos and neg posts to the 12 volt battery charger.
Not on any modern car with a 12 volt system.