Answer:
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Explanation:
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In this case, since the combustion of B2H6 is:
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Thus, since there is 1:2 mole ratio between the reactant and product, the produced grams of the latter is:
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Answer:
3.11%
Explanation:
We express a solution's volume by volume percent concentration, % v/v,
Take the ratio of the isopropyl alcohol (IPA) volume to the total volume of the solution, which is 1400 mL of water+ 45 mL of IPA,
and multiply by 100 to get the percentage: 45/(1400+45) *100 = 0.0311*100 = 3.11%
Zn⁰ ----> Zn⁺² + 2e⁻ - oxidation
Hg⁺² + 2e⁻ ----> Hg⁰ - reduction
Zn loses 2 moles of electrons , and Hg gains 2 mole of electrons.
So, number of moles of electrons gained and lost during reaction is equal.
A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.
Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).
For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.
Activation energy of reverse and forward reactions is related by:
Activation energy of reverse rxn = Activation energy of forward rxn - ΔH rxn
=> Activiation energy of reverse rxn = 102 kJ/mol - 55 kJ/mol = 47 kJ/mol
Answer: 47 kJ/mol