answer:
A
explanation:
it have to be balanced to form water
and water is H2O
Answer:
the UK and Ireland for your business
Answer:
Options A, C and D.
Explanation:
Oxidation is the loss of electrons during a reaction by a molecule, atom or ion. It is represented by an increase in the oxidation number.
Reduction is the loss of electrons during a reaction by a molecule, atom or ion. It is represented by a decrease in the oxidation number.
Both processes makes up what we know as Redox (REDuction - OXidation) reactions.
Note: The oxidation number of an element in its ground state is 0.
To identify which reactions are redox, we look out for change in oxidation number of the molecule, atom or ions involved.
A) Al has an increase in oxidation number for 0 (reactant side) to +3 (product side), Silver moves from +1(reactant) to 0 (product side). this means Al was oxidized and Ag+ was reduced. This is a redox reaction.
B) All atoms involved retains their oxidation number. S= +6, O =-2, H =+1. This is not a redox reaction.
C) Ba has an increase in oxidation number form 0 to +2, while Cl has a decrease in oxidation number form 0 to -2. This is a redox reaction.
D) Mg has an increase in oxidation number form 0 to +2, while Br has a decrease in oxidation number form 0 to -2. This is a redox reaction.
Answer: The standard enthalpy change for this reaction is -116 kJ
Explanation:
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given chemical reaction is,
Now we have to determine the value of for the following reaction i.e,
According to the Hess’s law, if we reverse the reaction then the will change its sign and if we half the reaction, then the
So, the value for the reaction will be:
Hence, the standard enthalpy change for this reaction is -116 kJ