Cat urine. May sound weird, may get it wrong, but it's true. Your teacher'll freak out.
<span>this
could be a substitution reaction. as you will locate, between the
hydrogen's on the propane chain replaced into substituted for a Br from
Br2. that's particularly no longer a addition reaction! addition
reactions artwork once you have a AlkENE! by using fact that's an AlkANE
it would not have a double bond to act as a nucleophile to attack the
Br2 (which might act as a electrophile to boot reactions).</span>
Answer:
Explanation:
Depression in freezing point is given by:

= Depression in freezing point
i= vant hoff factor = 1 (for non electrolyte like urea)
= freezing point constant = 
m= molality

Weight of solvent (X)= 950 g = 0.95 kg
Molar mass of non electrolyte (urea) = 60.06 g/mol
Mass of non electrolyte (urea) added = ?


Thus
urea was dissolved.
Answer: 50 degrees Celsius is hotter than 50 degrees F. 50 degrees Celsius is half way between freezing and boiling