18- The number of orbitals in each sublevel are: A:-s:2, p:3, d:10, and f:14
B:-s:2, p:6, d:10, and f:14
C:-s:1, p:3, d:5, and f:7
D:-s:1, p:2, d:3, and f: 4

s2,p6,d10,f14

S contains 2 orbitals

P contains 6 orbitals

D contains 10 orbitals

F contains 14 orbitals

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"