There is no way to check. Synthetic urine is chemically equivalent to real urine. However most labs check the temperature of the urine and know the exact temperature it should be at the moment you give it to them. That's how most people get caught.
No
Some labs do and some labs don't. To be safe, I would assume that they do. It is very easy to distinguish male urine from female urine.
Synthetic is the term you are looking for i believe.
After opening and heating once how long does synthetic urine last
No. Synthetic urine is a thing. Felonies are crimes, and describe actions, not things. Purchasing or producing synthetic urine may be a felony, but the substance itself cannot be felonious.
only to eat
no
Drug users commonly use synthetic urine to pass drug tests required by employers and probation officers. Synthetic urine is made of sodium chloride of barium nitrate (depending on blood type) and red food dye.
No, because it is simply not urine.
Some brands synthetic urine are detectable (multi or one panel tests), better use clean friend to help you. Also many big pharmacy keep on stock 12 panel tests.. so you can check out your friend.
No, it is not safe to reuse synthetic urine. Once synthetic urine has been used, it is contaminated and should not be reused. Using contaminated urine may lead to inaccurate results in drug tests and other applications.
They Could Tell Its Not Real Urine And You Could Get In Trouble