The given question is incomplete. The complete question is ;
A student dissolves of 15 g aniline in 200 ml of a solvent with a density of 1.05 g/ml. The student notices that the volume of the solvent does not change when the aniline dissolves in it. Calculate the molarity and molality of the student's solution. Be sure each of your answer entries has the correct number of significant digits.
Answer: The molarity is 0.81 M and molality is 0.82 m
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.
where,
n= moles of solute
= volume of solution in ml = 200 ml
Now put all the given values in the formula of molarity, we get
Thus molarity is 0.81 M
Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.
where,
n = moles of solute
= weight of solvent in g
Mass of solution = 
mass of solvent = mass of solution - mass of solute = (210 - 15) g = 195 g
Now put all the given values in the formula of molality, we get
Therefore, the molality of solution is 0.82m
Answer:
5. gains two electrons.
Explanation:
In order to determine the most stable monoatomic ion of oxygen, we need to consider the octet rule: atoms will gain, lose or share electrons to complete their valence shell with 8 electrons.
Oxygen is in the Group 16 in the Periodic Table, so it has 6 valence electrons. Therefore, it will gain two electrons to have the electron configuration of the closest noble gas.
Answer:
<em>B.</em><em> </em><em>It </em><em>is </em><em>spontaneous </em><em>at </em><em>5</em><em>0</em><em>0</em><em>k</em><em> </em>
Answer:
There are 
moles of bactoX present in a 3.0 μL sample volume that contains 7.512×106 bacterial cells
Explanation:
Given that:
The number of molecules present in one bacterial cell is 
molecules
and the sample contains 
molecules.
Number of moles = number of molecules /Avogadro's number
where;
Avogadro's number = 6.023 × 10²³
Number of moles = 
Number of moles = 
moles
So; moles is present in one bacteria cell
Similarly; the sample contains molecules.
Therefore; the number of moles present in the bactoX is = 
= moles
