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.
i mean technically, no. only because water is water and water makes things wet. you know? unless you pour water onto water then idk honestly, truly...
Answer: M = 0.036 M
Explanation: Solution attached:
First convert mass of NH3 to moles
Next convert volume in mL to L
Use the formula for Molarity
M = n / L
and
.
Assuming complete decomposition of both samples,
First compound:
;
of the first compound would contain
Oxygen and mercury atoms seemingly exist in the first compound at a
ratio; thus the empirical formula for this compound would be
where the subscript "1" is omitted.
Similarly, for the second compound
;
of the first compound would contain
and therefore the empirical formula
.
B- 90 grams bc 45 mL times 2 equals 90