Ok to answer this question we firsst need to fin the number of mol of Urea (CH4N2O). to do this we simply :
1 mol of urea =15/60.055 = 0.25mol
therefore 200g of water contain 0.25mol
the next step is to determine the malality of our solution in 200g of water, to do this we say:
200 g = 1Kg/1000g = 0.2kg
therefor 0.25mol/0.2Kg = 1.25mol/kg
and from the equation:
we know that i = 1
we are given Kf
b is the molality that we just calculated
therefore;
the solutions freezing point is -2.325°C
Answer: a. 79.6 s
b. 44.3 s
c. 191 s
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
b) for completion of 32% of reaction
c) for completion of 81 % of reaction
Answer:
I'll take a gander at your question
Explanation:
If you mean the Earth's crust, your answer is The Mantle.
Answer:
25 g/hr
Explanation:
Remember that the rate of reaction refers to the rate at which reactants are used up or or the rate at which products appear.
Hence;
Rate of reaction = mass of reactant used up/time taken
Mass of reactant used up= 2g
Time taken = 5 minutes or 0.08 hours
Rate of reaction = 2g/0.08 hours = 25 g/hr