Classify the bonds formed between each pair as ionic, polar covalent, or nonpolar covalent based solely on each element's position on the periodic table.

o-o, fe-o, al-n, o-i, s-i, br-br, p-br, be-cl

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.