Answer: 873 kJ of energy will be required to break two moles of hydrogen gas.

Above chemical equation shows that two moles of hydrogen gas is reacting with one mole of oxygen gas to give two mole of water molecule.
Bond energy of H-H = 436kJ
According to reaction we have two moles hydrogen,so energy required to break the
H-H bond in two moles of hydrogen gas will be:

= 872kJ
872kJ of energy will be required to break H-H bond in two moles of hydrogen gas.
The average atomic mass of oxygen is the atomic mass with respect to 1/12th the mass of a C-12 atom, related to natural abundance.
amu - atomic mass units
O-16 - 15.995 amu
O-17 - 16.999 amu
O-18 - 17.999 amu
the average atomic mass is 15.9994 amu
average atomic mass = ∑atomic mass of each isotope * relative abundance percentage
in other words the average atomic mass is closer to the atomic mass of the most abundant isotope. In this case 15.9994 is closest to 15.995 amu which is the atomic mass of O-16.
This means that O-16 is the most abundant isotope.
The sponge is unsaturated when it is taking in more water. It becomes saturated when it stops taking in water. It is supersaturated when water starts oozing out from the sponge.
A saturated solution contains just as much solute as it normally hold at a particular temperature. An unsaturated solution contains less solute than it can normally hold at a particular temperature. A supersaturated solution contains more solute than it can normally hold at a particular temperature.
We can use a sponge to model these three scenario as follows;
Water continues to enter into the sponge when it is unsaturated, this continues until the sponge becomes saturated with water and takes in no more water. When the sponge becomes supersaturated, water begins to ooze out from the sponge because it can no longer hold more water.
Learn more: brainly.com/question/1527403
Mass defect and binding energy are related as
ΔE = Δmc^2
Where
ΔE = binding energy
Δm = mass defect
c = speed of light
given
mass defect = 3.09x 10-27 kg
We know that speed of light = 3 X 10^8 m /s
ΔE = 3.09x 10-27 kg (3 X 10^8 m /s)^2 = 2.781 X 10^-10 J / Kg
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