Question

1)Describe the process you would go through to find the number of valence electrons for any of the main group (columns 1-8) elements.2) Although both sugar and salt are soluble in water, the way in which they dissolve is different. Explain how their dissolving process is different and elaborate why these differences exist. 3)Do you think one gram of sucrose or one gram of sodium chloride will melt at a higher temperature? Explain your answer. 4)

Using chemical nomenclature name the following ionic compounds: 

NaCl

KBr

MgO

Answer 1

1)Describe the process you would go through to find the number of valence electrons for any of the main group (columns 1-8) elements.

we group them via families or "columns"

each family "number" accounts for the valence electrons shown, for instance

alkali metal --> group 1, must have 1 electron in its valence shell

For halogens, family 7, then, 7 electrons are in the  valence shell

.2) Although both sugar and salt are soluble in water, the way in which they dissolve is different. Explain how their dissolving process is different and elaborate why these differences exist.

salt will dissociate into ions, each ion will attract the opposite

NaCl(aq) --> Na+(aq) + Cl-(aq), each ion will get solvated by H2O each sonsiting of their respecitv epositivE/negative dipole

sugar will get dipoles of water similar to the salt but will NOT form ionic species, this is mainly just due to dipole-dipole interactions between the solvent + solute

3)Do you think one gram of sucrose or one gram of sodium chloride will melt at a higher temperature? Explain your answer.

1 gof sucrose --> molecular, should have a lower melting point, since it has weaker interacitons

1 g of NaCl --> iwll have a very high melting point, ionic interacitons require lots of oenergy to break between the ions...

4)

Using chemical nomenclature name the following ionic compounds: 

NaCl -_> Na+ + Cl- --> Sodium chloride

KBr --> K+ + Br- --> Potassium bromide

MgO --> Mg2+ + O2- --> Magnesium oxide