Answer:
a) 7.0.
b) Nickel sulfate hepta hydrate.
c) 280.83 g/mol.
d) 44.9%.
Explanation:
<u><em>a) What is the formula of the hydrate?</em></u>
The mass of the hydrated sample (NiSO₄.xH₂O) = 5.0 g,
The mass of the anhydrous salt (NiSO₄) = 2.755 g,
The mass of water = 5.0 g - 2.755 g = 2.245 g.
∴ no. of moles of water = mass/molar mass = (2.245 g)/(18.0 g/mol) = 0.1247 mol.
∴ no. of moles of anhydrous salt (NiSO₄) = mass/molar mass = (2.755 g)/(154.75 g/mol) = 0.0178 mol.
∴ water of crystallization in the sample (x) = no. of moles of water/no. of moles of anhydrous salt (NiSO₄) = (0.1247 mol)/(0.0178 mol) = 7.0.
<u><em>b) What is the full chemical name for the hydrate?</em></u>
The name of the salt (NiSO₄.7H₂O) is Nickel sulfate hepta hydrate.
<u><em>c) What is the molar mass of the hydrate? </em></u>
(NiSO₄.7H₂O)
The molar mass = molar mass of NiSO₄ + 7(molar mass of H₂O) = (154.75 g/mol) + 7(18.0 g/mol) = 280.83 g/mol.
<em><u>d) What is the mass % of water in the hydrate?</u></em>
The mass % of water = (mass of water)/(mass of hydrated sample) x 100 = (2.245 g)/(5.0 g) x 100 = 44.9%.
Explanation:
a) Anode:
Cathode :
b)
c) As , the reaction is spontaneous.
d)
Explanation:
a) Here Ni undergoes oxidation by loss of electrons, thus act as anode. Hydrogen undergoes reduction by gain of electrons and thus act as cathode.
Anode:
Cathode :
b) The representation is given by writing the anode on left hand side followed by its ion with its molar concentration. It is followed by a slat bridge. Then the cathodic ion with its molar concentration is written and then the cathode.
c)
Where both are standard reduction potentials.
= +ve, reaction is spontaneous
= -ve, reaction is non spontaneous
= 0, reaction is in equilibrium
Thus as , the reaction is spontaneous.
d) The standard emf of a cell is related to Gibbs free energy by following relation:
= standard gibbs free energy
n= no of electrons gained or lost
F= faraday's constant
= standard emf
Thus value of Gibbs free energy is -48250 Joules.
Pushing down a piston in an airtight cylinder would tend to increase the pressure in the system since the particle collision and collisions with the walls are now more frequent. Also, pushing further, the gas would undergo a phase change from gas to a liquid.
Answer:
The boiling point of 1-chlorobutane is substantially lower than that of 1-butanol
Explanation:
Fractional distillation is a separation process based on difference in boiling point of two compounds.
1-chlorobutane is a polar aprotic molecule due to presence of polar C-Cl bond. Hence dipole-dipole intermolecular force exists in 1-chlorobutane as a major force.
1-butanol is a polar protic molecule. Hence dipole-dipole force along with hydrogen bonding exist in 1-butanol.
Therefore intermolecular force is stronger in 1-butanol as compared to 1-chlorobutane.
So, boiling point of 1-butanol is much higher than 1-chlorobutane.
Hence mixture of 1-chlorobutane and 1-butanol can be separated by fractional distillation based on difference in boiling point.
So, option (D) is correct.
Answer:
Group 12
Explanation:
Group 12 is also called a transition metal group. This group in the periodic table lies in between the groups or tables. These metals are classified as the transition metal in the table.
These metals are found from the group number 3 to 12. In the periodic table, These transition elements are ductile and malleable. These metal conduct heat and electricity.
These elements are generally called dense and less to react to the alkaline metal. Iron, copper-silver, gold is the most important transition metal.