11. Atomic numbers of elements A, B, C and D are 3, 9, 11 and 17 respectively. Identify two pairs amongst the elements which have similar chemical properties. Which pair is likely to be metallic in character? fleaz helf me ||_|| I'm crying

3. if the dartboard below is used to model an atom, which subatomic particles would be located at z?

Consider the following reaction at equilibrium. 2co2 (g) 2co (g) + o2 (g) h° = -514 kj le châtelier's principle predicts that the equilibrium partial pressure of co (g) can be maximized by carrying out the reaction a. at high temperature and high pressure b. at high temperature and low pressure c. at low temperature and low pressure d. at low temperature and high pressure e. in the presence of solid carbon

Calculate the energy required to ionize a hydrogen atom to an excited state where the electron is initially in the n = 5 energy level. report your answer in kilojoules