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Flashcards in C4c Deck (7):
1

What do ionic compounds form?

-ionic bond for between metals and non-metals and always make giant ionic lattices
-ions form a closely packed
-ions not free to move so the compounds do not conduct electricity when solid
-very strong chemical bonds between all the ions

2

What are the properties of NaCl and why?

-giant ionic structure
-high melting and boiling point due to very strong attraction between oppositely charged ions in the giant structure
when melted ions are free to move and will conduct electricity
-dissolves to form solution that conducts electricity (ions dissolve and separate so are free to move in the solution, so they carry electric current)
-Na+ and Cl- ions

3

What are the properties of MgO and why?

-giant ionic structure
-high melting and boiling point due to very strong attraction between oppositely charged ions in the giant structure
-Mg2+ and O2- ions (double the charge of NaCl
-higher melting point than sodium chloride:
*as it has double the charge of NaCl, so the attraction is harder to overcome
*O2- ions are smaller than Cl- ions, so ions in MgO more dense , also making the attraction harder to overcome
-when melted ions are free to move and will conduct electricity

4

What are ions and how are they formed?

-charge particles, can be a single atom(Cl-) or a group of atoms(NO-3)
-non metal: gain electrons to form negative ions
-metal: lose electrons to form positive ions

5

What is ionic bonding?

-atoms losing or gaining electrons to form charged particles (ions) which are then strongly attracted to each other (because of the attraction of opposite charges)

6

Why are the boiling and melting points of molecular substances low?

-atoms within the molecules are help together by very strong covalent bonds
-by contrast, the forces of attraction between these attractions are very weak
-because of these feeble intermolecular forces, they have very low boiling and melting points

7

What are some properties of molecular substances?

-substances formed from covalent bonding usually have simple structures (CO2)
-most are liquids or gases at room temperature
-don't conduct electricity, because there are no free electrons or ions