The question incomplete , the complete question is:
A student dissolves of 18.0 g urea in 200.0 mL of a solvent with a density of 0.95 g/mL . The student notices that the volume of the solvent does not change when the urea dissolves in it. Calculate the molarity and molality of the student's solution. Round both of your answers to significant digits.
Answer:
The molarity and molality of the student's solution is 1.50 Molar and 1.58 molal.
Explanation:
Moles of urea = 
Volume of the solution = 200.0 mL = 0.2 L (1 mL = 0.001 L)

Molarity of the urea solution ;

Mass of solvent = m
Volume of solvent = V = 200.0 mL
Density of the urea = d = 0.95 g/mL


(1 g = 0.001 kg)
Molality of the urea solution ;


The molarity and molality of the student's solution is 1.50 Molar and 1.58 molal.
Answer:
N, B, Be, C
Explanation:
N (Nitrogen) has 14.0067 B (Boron) has 10.81 Be (Beryllium) has 9 and C (Carbon) has 12
Answer:
An amide may be produced by reacting an acid chloride with ammonia.
Answer:
Ammonia gas reacts with oxygen gas.
Nitric oxide gas and liquid water are produced.
Platinum is used as a catalyst.
The equation is unbalanced because the number of hydrogen atoms is not the same on both sides of the equation.
Explanation:
Answer:
![[H^+]=0.00332M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D0.00332M)
Explanation:
Hello,
In this case, considering the dissociation of valeric acid as:

Its corresponding law of mass action is:
![Ka=\frac{[H^+][C_5H_9O_2^-]}{[HC_5H_9O_2]}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH%5E%2B%5D%5BC_5H_9O_2%5E-%5D%7D%7B%5BHC_5H_9O_2%5D%7D)
Now, by means of the change
due to dissociation, it becomes:

Solving for
we obtain:

Thus, since the concentration of hydronium equals
, the answer is:
![[H^+]=x=0.00332M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3Dx%3D0.00332M)
Best regards.