Question

1. A $2M$ solution of urea $(C{H_4}{N_2}O)$ can be prepared by dissolving $1$ mole of urea in $500ml$ water.
2. Urea is a non-polar molecular compound.
A. Statement $1$ is true, statement $2$ is true.
B. Statement 1 is true, statement 2 is false.
C. Statement 1 is false, statement 2 is true.
D. Statement 1 is false, statement 2 is false.

Answer 1

Hint: At first we will know about Urea and its composition. Then we will know what molality is and will calculate the molality of the solution and compare it with the value given in the question. Then we will know whether the Urea is polar or not. We will find a reason about why it is polar.

Complete Step by step Solution:
Step1: Urea, chemical formula $C{H_4}{N_2}O$ . It is also known as carbamide. It is a major compound of the human urine, and waste products of many living organisms. It is extensively used in agriculture. More than 90% of urea is made just for agriculture only.
Step2. Molarity is the total moles of solute in the 1 litre of the solvent.
$Molarity = \dfrac{{moles of solute}}{{Volume(L)}}$
Step3. We will look into the given data in the question:
Number of moles of urea: $1$ mole
Volume of Urea: $500ml$
Step4. Molarity of urea : $\dfrac{{Moles}}{{Volume(L)}}$
$ \Rightarrow \dfrac{1}{{0.5L}} = 2M$
Hence the Statement is is true the molarity is $2M$.
Step5: Urea is a polar compound. The bond between the carbon and oxygen has high difference between electronegativity. The polarity is increased by the donation of lone pairs by the nitrogen atom to the pi-bond between carbon and oxygen. The partial negative and positive charges are formed increasing its polarity.
Hence the statement 2 is false.

So, the correct Option is B.

Note: Soil bacteria contain the enzyme urease, which acts as catalyst of urea to ammonia. The urea rapidly converts into the ammonium form in the soil. It makes the soil nitrogen rich. It is also soluble in water, it is very suitable for use in fertilizer solution.