The atomic radius decreases across a period from left to right and increases down a given group. The atoms with the largest atomic radii are located in group l and at the bottom of groups. Moving from left to right across a period, electrons are added one at a time to the outer energy shell. Hope this helps!
3rd one sorry if it’s wrong
Answer:
For number 5 it is the 2nd one some stants has a mass of 1.25 g And the 2nd 1 number 6It is the 1st 1A subject has a melting point of 40
The number of moles of moles of Magnesium,chlorine and oxygen atoms in 7.80 moles of Mg(ClO4)2 is calculated as below
find the total number of each atom in Mg(ClO4)2
that is mg = 1 atom
Cl = 1x2 = 2 atoms
O = 4 x2 = 8 atoms
then multiply 7.80 moles with total number of each atom , to get the number moles of each atom
that is
Mg = 7.80 x1= 7.80 moles
cl = 7.80 x2=15.6 moles
O = 7.80 x8= 62.4 moles
Oxygen carbon and hydrogen