A certain diprotic acid H2X is a strong acid in its first deprotonation and a weak acid in its second deprotonation. A solution of H2X that is initially 0.020 M has a pH of 1.66. What is the value of Ka2for this acid

c (diamond),

sio2 (quartz)

diaria maybe go see a doctor about that

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.