Consider the intermediate chemical reactions.
ca(s) + co2(g) + o2(g) - cacos(s) ah, = -812.8 kj
2 ca(s)+ o2(g) → 2cao(s)
ah, = - 1,269.8kj
the final overall chemical equation is cao(s) + co2(g) → caco3(s). when the enthalpy of this overall chemical equation is
calculated, the enthalpy of the second intermediate equation
is halved and has its sign changed.
is halved.
has its sign changed.
is unchanged.

How can one make a supersaturated solution? (apex)

The sum of the oxidation numbers in a neutral compound is always

Which of the following represents a balanced nuclear equation showing bismuth-212 undergoing alpha decay followed by beta decay? (2 points) superscript 212 over subscript 83 bi yields superscript 4 over subscript 2 he + superscript 208 over subscript 81 tl yields x−superscript 208 over subscript 82 pb + superscript 0 over subscript -1 beta superscript 212 over subscript 83 bi + superscript 0 over subscript -1 beta yields superscript 4 over subscript 2 he + superscript 208 over subscript 81 tl yields x−superscript 208 over subscript 82 pb superscript 216 over subscript 85 as yields superscript 4 over subscript 2 he + superscript 216 over subscript 85 as yields superscript 216 over subscript 85 pb + superscript 0 over subscript -1 beta superscript 212 over subscript 83 bi yields superscript 0 over subscript -1 beta + superscript 208 over subscript 81 tl yields superscript 208 over subscript 82 pb + superscript 4 over subscript 2 he