How many elements and atoms are in chalk

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.

In the reaction between a crushed antacid tablet and vinegar what gas is emitted

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?