What is the total number of electrons needed to completely fill all of the orbitals in an atoms second principal energy level

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

How many moles of no2 will form when 3.3 moles of cu are reacted with excess hno3?

Use the periodic table to identify the number of core electrons and the number of valence electrons in each case below. potassium (k): 1s22s22p63s23p64s1