ch. 4 Flashcards
What’s the difference between a ball and stick model and a space filling model of a compound
-ball and stick model shows the amount of atoms –space filling model shows the size of atoms in a molecule
why is it easier to separate substances in a mixture than the elements in a compound
mixtures are combined physically and can be separated physically, compounds have to be separated chemically
Chemical bond
An attractive bond that holds atoms together
ionic substances
metal and non-metals
solids at room temp
compounds made up of ions
Molecular substances
Non-metal and nonmetal
made up of molecules
can be solid liquid or gas at room temperature
How does the structure of a substance affect its properties
Very strong bonds = harder to break
weak bonds = easier to break
ionic compounds are
Held together by very strong bonds
-Therefore it requires higher temperatures to break bonds
Bonds of molecular substances are
Weaker
so it requires less heat to break bonds
Network structure
high bonds+ high melting point
Which substance melts easier sugar or salt?
sugar melts easier because it’s a molecular substance meaning the bond is weaker
why do atoms bond
To become more stable
ionic bonds are formed between oppositely charged..
ions
covalent bonds are formed by the ___ between atoms
Sharing of electrons
covalent bonds are ___conductors of electricity
poor
Nonpolar covalent bonds
Bonds in which atoms share electrons equally
