A hydrated sample of cobalt II chloride has a molar mass of 309.99 g/mol. What is the mole ratio between cobalt II chloride and
2 answers:
Answer:
Explanation:
First, identify the formula of cobalt II chloride: CoCl₂
Next, find the molar mass of CoCl₂. Identify the individual element's mass.
- Cobalt (Co): 58.93319 g/mol
- Chlorine (Cl): 35.45 g/mol
Since there is a subscript of 2 after the Cl, we must multiply the molar mass of chlorine by 2
- CoCl₂: (58.93319 g/mol) + (2* 35.45 g/mol) = (58.93319 g/mol)+(70.9 g/mol)
- 129.83319 g/mol
Assuming the sample is 1 mole, we can subtract the mass we just found from the hydrate sample's mass. This is the mass of the water.
- 309.99 g - 129.83319 g= 180.15681 g
Now, we need to find the number of moles of water. Begin by finding the molar mass of water: H₂O
- Hydrogen (H): 1.008 g/mol
- Oxygen (O): 15.999 g/mol
Since there is a subscript of 2 after the H, we must multiply the molar mass of hydrogen by 2.
- H₂O: (1.008 g/mol *2)+ 15.999 g/mol = (2.016 g/mol)+(15.999 g/mol)=18.006 g/mol
Finally, divide the mass of the water by the molar mass of water.
- 180.15681 g / 18.006 g/mol
Note that the grams or g will cancel.
- 180.15681 / 18.006 mol = 10.00537654 mol
This is roughly 10, so we can round to 10.
- ≈ 10 mol H₂O
So, the mole ratio is 1 mole CoCl₂ to 10 mole H₂O
You might be interested in
Answer:
a)
In Boyle's Law, the variable that remains constant is the absolute temperature of the gas.
In Charle's Law, the variable that remains constant is the pressure of the gas.
In Avogadro's Law, the variables that remain constant are pressure and temperature of the gas.
b)
In Boyle's Law, the variables involved are pressure and volume: the law states that for a fixed mass of ideal gas at constant temperature, the pressure of the gas is inversely proportional to the volume:
where p is the pressure of the gas and V the volume.
In Charle's Law, the variables involved are volume and temperature: the law states that for a fixed mass of ideal gas at constant pressure, the volume of the gas is directly proportional to the temperature:
where V is the volume of the gas and T the temperature.
In Avogadro's Law, the variables involved are the volume and the number of moles: the law states that for an ideal gas kept at constant pressure and temperature, the volume of the gas is directly proportional to the number of moles:
Where V is the volume of the gas and n the number of moles.
c)
See the graphs of the three Laws in attachment:
- First graph: Boyle's Law, which shows that the pressure of the gas is inversely proportional to the volume
- Second Graph: Charle's Law, which shows that the volume of the gas is directly proportional to the absolute temperature
- Third graph: Avogadro's Law, which shows that the volume of the gas is directly proportional to the number of moles of the gas
d)
Here we want to re-write the three laws by making V the subject.
For Boyle's law, we get:
For Charle's Law, we get:
For Avogadro's Law, we get:
Therefore, we see that the two laws that show a direct proportionality are Charle's Law and Avogadro's Law, while Boyle's Law shows an inverse proportionality between the two variables.
Answer:
D. All of them would have the same kinetic energy
Explanation:
The expression for the kinetic energy of the gas is:-
k is Boltzmann's constant =
T is the temperature
<u>Since, kinetic energy depends only on the temperature. Thus, at same temperature, at 300 K, all the gases which are will posses same value of kinetic energy.</u>