Can some please help me understand what this means!! Write the electron configurations of the following elements. Only write them as noble gas or full if it states to do so.

1. Phosphorus (P) Full configuration :

2. Ruthenium (Ru) Full configuration :

3. Barium (Ba) Noble gas configuration :

4. Thorium (Th) Noble gas configuration :

Phosporus- 1s2 2s2 2p6 3s2 2p3

Ruthenium- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d6

Barium- (Xe)6s2

Thorium- (Rn) 6d2 7s2

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.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2