Answer:
Cool air moves down while hot air rises
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.
Answer:
C. Mole
Explanation:
Chemical formula deals with mole number
Calculate the mass of water used
that is
100-22.2=77.8g convert into Kg = 77.8/1000=0.0778Kg of water
then calculate the moles of HCOOH used
that is 22.2g/molar mass of HCOOH(1+12+16+16+1)=46
therefore the moles of HCOOH=22.2/46=0.48moles
the mole of water= 77.8/18(molar mass of water= 4.32moles
the molarity of HCOOH = 0.48mol/0.0778kg=6.17M
The mole ratio= moles of HCOOH divided by total moles
the total moles= 0.48+4.32=4.8moles
therefore the mole ratio= 0.48/4.8moles=0.1(the moles fraction of HCOOH)
Answer:
Student 3
Explanation:
This question lets us know something about how the density of a gas varies with temperature.
When a gas is heated, its molecules spread out and expand. When this happens, the volume of the gas increases. Remember that density is defined as mass/volume. Thus as the volume increases, the density of the gas decreases.
Therefore, the carbon dioxide rose up because the heat expanded the gas and it became less dense.