The formula for the pH of a solution of hydronium ions is given by the logarithmic equation pH= -log[h3o^+], where [H3o^+] is the hydronium ion concentration. Find the pH of a certain agricultural product with the hydronium ion concentration of 4.7x10^-4 The pH is =?

iron and sleel

make siroeel

the answer is either b or c

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.