Give the molecular geometry of each central atom: nitrogen, middle carbon, right carbon,

respectively.

1. linear, angular, tetrahedral

2. angular, angular, tetrahedral

3. angular, trigonal planar, tetrahedral

4. linear, linear, linear

5. linear, tetrahedral, tetrahedral

6. tetrahedral, tetrahedral, tetrahedral

7. trigonal planar, trigonal planar, tetrahedral

8. trigonal planar, trigonal planar, trigonal

planar

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.