<u>Answer:</u> The average of the densities of the given measurements is 1.363 g/mL
<u>Explanation:</u>
The equation used to calculate density of a substance is given by:
We are given:
First measured value of density, = 1.019 g/mL
Second measured value of density, = 1.498 g/mL
Third measured value of density, = 1.572 g/mL
Putting values in above equation, we get:
Hence, the average of the densities of the given measurements is 1.363 g/mL
Answer:
-514 kJ/mol
Explanation:
The bond enthalpy which is also known as bond energy can be defined as the amount of energy needed to split one mole of the stated bond. The change in enthalpy of a given reaction can be estimated by subtracting the sum of the bond energies of the reactants from the sum of the bond energies of the products.
For the given chemical reaction, the change in enthalpy of the reaction is:
Δ [2(409) + 4(388) + 3(496) - 4(630) - 4(463)] kJ/mol = 818 + 1552 + 1488 - 2520 - 1852 = -514 kJ/mol