Describe the manufacture of ethanol by: (a) fermentation of aqueous glucose at 25–35°C in the presence of yeast and in the absence of oxygen (b) catalytic addition of steam to ethene at 300°C and 6000 kPa/60 atm in the presence of an acid catalyst including a comparison of the advantages and disadvantages of the two methods

Describe the formation of covalent bonds in simple molecules, including \( H_2 \), \( Cl_2 \), \( H_2O \), \( CH_4 \), \( NH_3 \), \( HCl \), \( CH_3OH \), \( C_2H_4 \), \( O_2 \), \( CO_2 \) and \( N_2 \). Use dot-and-cross diagrams to show the electronic configurations in these and similar molecules