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A because dormant volcanoes are volcanoes that have not erupted in a long time but are expected to erupt again in the future
Answer:
2H2(g) + O2(g) --------> 2H2O(g). ∆H= -242KJmol-1
Explanation:
A thermochemical equation is a balanced chemical reaction equation that includes the physical states of all reactants and products and the energy change.
As shown above, hydrogen reacted with oxygen in the gas phase to form water, an energy of 242KJ was evolved and we are required to put this in a thermochemical equation using the least coefficients.
Hydrogen reacts with oxygen to form water in the gas phase in a least ratio of 2:1 as shown in the answer.
The term 'energy evolved' in the question means that the reaction is exothermic and energy is evolved. Hence ∆H is negative as shown.
Molality= mol/ Kg
if we assume that we have 1 kg of water, we have 3.19 moles of solute.
the formula for mole fraction --> mole fraction= mol of solule/ mol of solution
1) if we have 1 kg of water which is same as 1000 grams of water.
2) we need to convert grams to moles using the molar mass of water
molar mass of H₂O= (2 x 1.01) + 16.0 = 18.02 g/mol
1000 g (1 mol/ 18.02 grams)= 55.5 mol
3) mole of solution= 55.5 moles + 3.19 moles= 58.7 moles of solution
4) mole fraction= 3.19 / 58.7= 0.0543
