Calculate AH for the following reaction. C2H4(g) + H2(g) → C2H6(g)
(ΔHf° for C2H4(g) = 52.5 kJ/mol; ΔHf° for C2H6(g) = -84.7 kJ/mol)
a. -137.2 kJ
b. -32.2 kJ
c. 32.2 kJ
d. 137.2 kJ

a.-137.2 kJ

Explanation:

If the first example symbol used is addition you can copy the plus and follow it how to solve the next!And also if the negative or positive sign.

the correct answer is b. a strong acid completely dissociates to its ions when dissolved in water. completely dissociates to and ions. a is incorrect because does not fully ionize to and ions and some remain as the compound . c and d are incorrect because, and do not fall into the category of bronsted lowry acids. a bronsted lowry acid is a proton donor and since both molecules do not have a proton to donate they are not bronsted lowry acids. likewise,   if we use the lewis acid definition, they cannot be acids. a lewis acid is an electron pair acceptor. both and have a complete octet so can not accept any electrons which disqualifies them as acids.

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.