The reaction;
O(g) +O2(g)→O3(g), ΔH = sum of bond enthalpy of reactants-sum of food enthalpy of products.
ΔH = ( bond enthalpy of O(g)+bond enthalpy of O2 (g) - bond enthalpy of O3(g)
-107.2 kJ/mol = O+487.7kJ/mol =O+487.7 kJ/mol +487.7kJ/mol =594.9 kJ/mol
Bond enthalpy (BE) of O3(g) is equals to 2× bond enthalpy of O3(g) because, O3(g) has two types of bonds from its lewis structure (0-0=0).
∴2BE of O3(g) = 594.9kJ/mol
Average bond enthalpy = 594.9kJ/mol/2
=297.45kJ/mol
∴ Averange bond enthalpy of O3(g) is 297.45kJ/mol.
When light travels from air into water,it slows down,causing it to change directions slightly
D) burning magnesium ribbon, as combustion is a chemical reaction so causes chemical change. The other 3 options do not involve reactions so there isn't a chemical change.
C. single replacement. A single replacement is represented by this formula : AB + C = AC + B
Distance traveled by the race horse=6 furlongs
Converting the distance from furlongs to rods: 40 rods =1 furlong
Converting the distance from rods to yards, feet and miles: 5.5 yards = 1 rod, 3foot =1 yard, 1 mile = 5280 feet.
The given speed of race horse = 40.7mi/hr
Calculating the time required:
Therefore, 66.34 s is required for a race horse to run six furlongs at 40.7 miles per hour.