Considerando as equações abaixo: 5
C2H2(g) +5026) 2 CO2(g) + H2050 AH = – 1.299,5 kJ
Cigr) + O2(g) + CO2(g) AH = – 393,5 kJ
1
H2(g) + 2 02(0) H20) AH 5 – 285,8 k]
Calcule a variação de entalpia da reação:
2 C(gr) + H2(g) → C2H2(g)
O (A) +226,7 kJ
O (B) +620,2 kJ
O(C) +798,3 ku
(D) -1.978,8 kJ
(E)-2.372,3 kJ

in theory, limestone is composed principally of the compound calcium carbonate - caco3, but in reality this compound is deposited in conditions involving a number of other compounds as impurities so it ends up being a mixture of many compounds.

hope this : -)

tony (lordcaos066)

answer; /// i do believe that the correct answer is (c)nuclear bond

well in order to answer this question you have to provide more information < 3