2.1) Draw the Lewis diagram of the phosphate ion, PO43 2.2) How many moles of OHmust be added to 6.50L of a HCl solution to change the pH from 4.82 to 5.22 ? You may assume the volume of the solution remains constant. (4) 2.3) Given the reaction: 2NOBr(g)2NO(g)+Br2(g),KC=2.01(100C) What is the partial pressure of NO(g) (in atm) at equilibrium, if the partial pressures of NOBr(g) and Br2(g) are 0.30atm and 0.50atm, respectively? (Hint: KP=KC(RT)n)(4) 2.4) State whether the following statements are TRUE or FALSE: (4) i. Effective nuclear charge decreases from left to right across the periodic table because the effect of shielding increases as more electrons are added to an orbital. ii. The density of an ideal gas is independent of temperature because the molecules of an ideal gas occupy no volume. 2.5) A0.505g sample of a metal carbonate, MCO3 containing unknown metal M, is heated to complete decomposition releasing 0.222g of CO2(G) and a leaving a metal oxide, MO(s) : MCO3(s)MO(s)+CO2(g) Which group 2 element is M? 2.6) Write the balanced chemical equation in alkaline solution. Show all balancing steps clearly: MnO4(aq)+SO3(aq)2Mn(aq)2++SO4(aq)2 2.7) Calculate the concentration of NH3(aq)(Kb=1.8105) necessary to initiate the precipitation of iron(II) hydroxide (KSP=1.61014) from a [Fe2+]=0.0030M (6) solution