Which reactions are redox reactions? check all that apply. check all that apply. 4li(s)+o2(g)→2li2o(s) mg(s)+fe2+(aq)→mg2+(aq)+fe(s) pb(no3)2(aq)+na2s?

The reaction s that are redox reactions are

4Li(s) +O2 (g)→ 2Li2O (s)\

Mg(s) +  Fe2+ (aq)→ Mg2+(aq) + Fe(s)

A redox reaction involve both oxidation and reduction. During redox reaction there is change in oxidation states. For example in

4Li +O2 →2Li2O  Li is oxidized  while O  is  reduced

in  Mg +Fe2+ → Mg2+ +Fe   Mg is oxidized since it move from oxidation state 0 to 2+ while Fe2+ is reduced since it move from oxidation state of 2+ to 0

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.