Answer:
(ΔHrxn) = 1.273kJ/mol
Explanation:
Applying
m=78.2, c= 3.97, ∆t= 25.8-21.7
(ΔHrxn)= mc∆t
=78.2× 3.97× 4.1= 1.273kJ/mol
Explanation:
probably because, X rays are used to ionise the gas molecules, which is loss of electrons, these electrons are absorbed by oil drops
Answer:
C. Balanced forces caused a change in the motion of the plates.
Explanation:
Scientists believe that Pangea broke apart for the same reason that the plates are moving today. The movement is caused by the convection currents that roll over in the upper zone of the mantle. This movement in the mantle causes the plates to move slowly across the surface of the Earth.
Answer: 1.19 V
Explanation:
Standard potential for an electrochemical cell is given by:
= standard electrode potential =
The 
values have to be reduction potentials.
Given:
Cadmium is losing electrons , undergo oxidation and thus act as anode. mercury is gaining electrons, undergo reduction and thus acts as cathode.
= standard electrode potential =
Thus the standard potential for an electrochemical cell with the cell reaction is 1.19 V.
Answer:
3.93 mol
Explanation:
The balanced equation is given as;
2 Fe₂S₃+ 9 O₂ --> 2 Fe₂O₃ + 6 SO₂
From the reaction;
2 mol of Fe₂S₃ reacts with 9 mol of O₂ to form 6 mol of 6 SO₂
This means;
1 mol of Fe₂S₃ requires 9/2 mol of O₂
Also,
1 mol of O₂ requires 1/9 mol of Fe₂S₃
In the question, we have;
1.31 moles of Fe2S3 and 22.8 moles of O2
The limiting reactant which determine how much of the product formed is; Fe₂S₃ because O₂ is in excess.
The relationship between Fe₂S₃ and SO₂ is;
2 mol Fe₂S₃ produces 6 mol of SO₂
1.31 mol of Fe₂S₃ would produce x mol ?
2 = 6
1.31 = x
x = 6 * 1.31 / 2 = 3.93 mol
