Calculate HRXN for the reaction: CaO(s)+CO2(g)CaCO3(s). Use the following reactions and given H's.
Ca(s)+CO2(g)+1/2 O2(g)--CaCO3(s) H=-812.8kJ
2 Ca(s)+O2(g)--2CaO(s) H=-1269.8kJ
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Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.