I would love to help but it is 3 or is it 3 million?
Answer:
CaCO3 + 2HCl ---> CaCl2 + H2O + CO2
Explanation:
The reaction between solid calcium carbonate and a mineral acid such as aqueous HCl is a neutralization reaction and occurs with the evolution of CO2 gas.
The balanced equation is given below
CaCO3 + 2HCl ---> CaCl2 + H20 + CO2
The product CaCl2 is water soluble which accounts for why the stain is removed, while CO2 gas escapes away from the reaction surface.
Answer : To balance a chemical equation you need to find the same number of molecules on both the sides of the reaction.
Here in the reaction ;

here we can see that I is not balanced so we need to balance that,
also nitrate is unbalanced we need to work on that as well.
so on solving we get,
Answer:
ΔH°f C₂H₅O₂N(s) = -537.2kJ
Explanation:
Based on the reaction:
4 C₂H₅O₂N(s) + 9O₂(g) → 8CO₂(g) + 10H₂O(l) + 2N₂(g)
ΔHrxn = ΔH°f products - ΔH°f reactants.
As:
ΔH°fO₂(g) = 0
ΔH°fCO₂(g) = -393.5kJ/mol
ΔH°fH₂O(l) = -285.8kJ/mol
ΔH°fN₂(g) = 0
The ΔHrxn is:
ΔHrxn = (8×-393.5kJ/mol + 10×-285.8kJ/mol) - (4×ΔH°fC₂H₅O₂N(s)) = -3857kJ/mol
-6006kJ/mol - (4×ΔH°fC₂H₅O₂N(s)) = -3857kJ/mol
-4×ΔH°fC₂H₅O₂N(s) = 2149kJ/mol
ΔH°fC₂H₅O₂N(s) = 2149kJ/mol / -4
<h3>ΔH°f C₂H₅O₂N(s) = -537.2kJ</h3>