The formula Fe2O3 tells us that one mole of Fe2O3 contains . A: 3 iron atoms and 2 oxygen atoms
B: 3 grams of iron and 2 grams of oxygen
C: 2 moles of iron atoms and 3 moles of oxygen atoms
D: 2 iron atoms and 3 oxygen atoms

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).

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.