The answer is B charged particles
Answer:
Look at the properties of Oxygen and Silicon - the two most abundant elements in the Earth's crust - by clicking on their symbols on the Periodic Table.
Explanation:
Answer:
Amount of heat energy released by light bulb = 25 joules
Explanation:
Given:
Energy receive by light bulb = 100 Joules
Energy released by light bulb as light energy = 75 Joules
Find:
Amount of heat energy released by light bulb
Computation:
We know that, energy is neither be created nor destroys
So,
Using Law of conservation of energy
Energy receive by light bulb = Energy released by light bulb as light energy + Amount of heat energy released by light bulb
100 = 75 + Amount of heat energy released by light bulb
Amount of heat energy released by light bulb = 100 - 75
Amount of heat energy released by light bulb = 25 joules
Enthalpy of formation is calculated by subtracting the total enthalpy of formation of the reactants from those of the products. This is called the HESS' LAW.
ΔHrxn = ΔH(products) - ΔH(reactants)
Since the enthalpies are not listed in this item, from reliable sources, the obtained enthalpies of formation are written below.
ΔH(C2H5OH) = -276 kJ/mol
ΔH(O2) = 0 (because O2 is a pure substance)
ΔH(CO2) = -393.5 kJ/mol
ΔH(H2O) = -285.5 kJ/mol
Using the equation above,
ΔHrxn = (2)(-393.5 kJ/mol) + (3)(-285.5 kJ/mol) - (-276 kJ/mol)
ΔHrxn = -1367.5 kJ/mol
<em>Answer: -1367.5 kJ/mol</em>
