For which of the following reactions does Kc equal Kp?*A. Sn(s) + 2H2O(g) <---> SnO2(s) + 2H2(g)B. 2C2H6(g) + 7O2(g) <----> 4CO2(g) + 6H2O(g)C. NH4Cl(s) <---> NH3(g) + HCl(g)D. N2(g) + 3H2(g) <----> 2NH3(g)

The relationship between Kc and Kp is given by the equation Kp = Kc(RT)^(Δn), where Δn is the change in moles of gas in the reaction (moles of gaseous products - moles of gaseous reactants), R is the ideal gas constant, and T is the temperature in Kelvin.

For Kc to equal Kp, Δn must be zero, meaning the number of moles of gaseous products must equal the number of moles of gaseous reactants.

Looking at the reactions:

A. Sn(s) + 2H2O(g) <---> SnO2(s) + 2H2(g) The number of moles of gaseous reactants is 2 (from 2H2O) and the number of moles of gaseous products is 2 (from 2H2). So, Δn = 2 - 2 = 0.

B. 2C2H6(g) + 7O2(g) <----> 4CO2(g) + 6H2O(g) The number of moles of gaseous reactants is 2 (from 2C2H6) + 7 (from 7O2) = 9 and the number of moles of gaseous products is 4 (from 4CO2) + 6 (from 6H2O) = 10. So, Δn = 10 - 9 = 1.

C. NH4Cl(s) <---> NH3(g) + HCl(g) The number of moles of gaseous reactants is 0 (since NH4Cl is a solid) and the number of moles of gaseous products is 1 (from NH3) + 1 (from HCl) = 2. So, Δn = 2 - 0 = 2.

D. N2(g) + 3H2(g) <----> 2NH3(g) The number of moles of gaseous reactants is 1 (from N2) + 3 (from 3H2) = 4 and the number of moles of gaseous products is 2 (from 2NH3). So, Δn = 2 - 4 = -2