As shown by the periodic table, why do the elements potassium and sodium have similar chemical properties?

Consider the reaction: n2(g) + o2(g) ⇄ 2no(g) kc = 0.10 at 2000oc starting with initial concentrations of 0.040 mol/l of n2 and 0.040 mol/l of o2, calculate the equilibrium concentration of no in mol/l how would this be done?

What is the molar mass of ca(cio4)2

What is the ph of a solution that has a hydrogen ion concentration of 1.0 * 10 -9 m?