Show how to work it out 1. 32.5grams of NaOH (sodium hydroxide) reacts an excess of CO2 (carbon dioxide). 2NaOH(s) + CO2(g) → Na2CO3(s) + H2O(1)

a. What is the theoretical yield of Na2CO3 in grams? 43.1g Na2CO3

b. If 16.45 g of Na2CO3 is formed, what is the percent yield? 38.2%

any far is the region can control the climate

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.