I don’t know so ask someone else
Answer:
Explanation:
Physical Change:
The changes that occur only due to change in shape or form but their chemical or internal composition remain unchanged.
These changes were reversible.
They have same chemical property.
These changes can be observed with naked eye.
Example
:
Water converting to Ice
Water converting to gas
In this water molecule remain the same only they rearrange themselves that change its state of mater not composition
Chemical changes:
The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.
These changes are irreversible
These changes occur due to chemical reactions
These may not be observed with naked eye
Example:
Combustion of fuel or wood: that oil or wood convert into energy, CO₂ and ash in case of wood
Boiling of egg: that change the chemical composition of protein in the egg
The reaction of Hydrogen and oxygen:
H₂ (g) + O₂ (g) -------------------------------------> 2H₂O (l)
Answer:
335 Joules kJ of heat will be released
Explanation:
Given the balanced equation:
8 Al (s) + 3 Fe3O4 (s) ----------> 4 Al2O3 (s) + 9 Fe(s),
ΔH = -3350*KJ/mol rxn
This is the heat released when 8 moles of Al react with 3 mol Fe3O4.
We then need to calculate the moles of reactants, verify if there is a limiting reagent and proceed to answer the question based on the soichiometry of the reaction.
Atomic weight Al = 26.98 g/mol Molecular Weight Fe3O4 = 231.53 g/mol
mol Al = 47.6 g/26.98 g/mol = 1.76 mol
mol Fe3O4 = 69.12 g/ 231.53 g/mol = 0.30 mol
Limiting reagent calculation:
8 mol Al / 3 mol Fe3O4 x 0.30 mol Fe3O4 = 0.80 mol Al are required and we have 1.76 mol, therefore Fe3O4 is the limiting reagent
Amount of Heat
-3350 kJ/ 3 mol Fe3O4 x 0.30 mol Fe3O4 = -335.00 kJ
The reason for this is that in almost all ionic compounds, there is an equivalent transfer and acceptance of the same number of electrons, whereby each transfer results in a + and receiver is a -. This ultimately cancels out when the ions come close together.