How is it possible to change the shape of your molecular models without breaking any of the covalent bonds?

A molecule's shape strongly affects its physical properties and the way it interacts with other molecules, and plays an important role in the way that biological molecules (proteins, enzymes, DNA, etc.) interact with each other.

Explanation:

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.