Answer:
Molar mass of vitamin K = 450.56\frac{g}{mol}[/tex]
Explanation:
The freezing point of camphor = 178.4 ⁰C
the Kf of camphor = 37.7°C/m
where : m = molality
the relation between freezing point depression and molality is
Depression in freezing point = Kf X molality
Where
Kf = cryoscopic constant of camphor
molality = moles of solute dissolved per kg of solvent.
putting values
2.69°C = 37.7°C/m X molality
molality = 0.0714 mol /kg

moles of vitamin K = 0.0714X0.025 = 0.00178 mol
we know that moles are related to mass and molar mass of a substance as:

For vitamin K the mass is given = 0.802 grams
therefore molar mass = 
Answer:
Deep ocean currents (also known as Thermohaline Circulation) are caused by: The sinking and transport of large masses of cool water gives rise to the thermohaline circulation, which is driven by density gradients due to variations in temperature and salinity. The earth's rotation also influences deep ocean currents.
Answer : The number of molecules present in nitrogen gas are,
Explanation :
First we have to calculate the moles of nitrogen gas by using ideal gas equation.
where,
P = Pressure of
gas =
(1 atm = 760 mmHg)
V = Volume of
gas = 985 mL = 0.982 L (1 L = 1000 mL)
n = number of moles
= ?
R = Gas constant =
T = Temperature of
gas =
Now put all the given values in above equation, we get:

Now we have to calculate the number of molecules present in nitrogen gas.
As we know that 1 mole of substance contains
number of molecules.
As, 1 mole of
gas contains
number of molecules
So,
mole of
gas contains
number of molecules
Therefore, the number of molecules present in nitrogen gas are,
Answer:
= 25.05°C
Explanation:
Given:
the value of ΔHcomb (heat of combustion) for dimethylphthalate (C10H10O4) is = 4685 kJ/mol.
mass = 0.905g of dimethylphthalate
molar mass = 194.18g dimethylphthalate
number of moles of dimethylphthalate = ???
= 21.5°C
= 6.15 kJ/°C
= ???
since we have our molar mass and mass of dimethylphthalate ;we can determine the number of moles as;
0.905g of dimethylphthalate × 
number of moles of dimethylphthalate = 0.000466 moles
Heat released = moles of dimethylphthalate × heat of combustion
= 0.000466 moles × 4685 kJ
= 21.84 kJ
∴ Heat absorbed by the calorimeter =

21.84 kJ =6.15 kJ/°C 
21.84 KJ = 
21.84 KJ =
- 132.225 kJ
21.84 KJ + 132.225 kJ = 
154.065 kJ = 
= 
=25.05°C
Matematically speaking, maybe because:
The number of substances = number of elements + number of different combinations of those elements