Ascorbic Acid is usually vitamin C. Take enough of it and it might kill you, but in any reasonable amount, it is beneficial to you.
no. if to much then yes but a reasonable amount no
If you swallow an acid based cleaning agent, call the local poison control center immediately.
it could be if you swallow it
yes
It is dead instantly.
Stomach acid also kills most bacteria that you might swallow with you food.
You probably have taken an aspirin then.
stomach
Sulfuric acid is highly corrosive, and would be fatal if ingested. It is not available for retail purchase.
Yes! If you swallow a penny, you will most likely die.
The pufferfish - the acid in it's organs can kill you instantly
Yes it can and will if you swallow enough. The liquid out of a wet cell battery contains Sulfuric Acid, which is deadly to humans if ingested.