What's the Matter?
Define the term "matter".
Matter = anything that has mass and takes up space.
Define the term "pure substance" and "mixture"
Pure Substance = A substance that is homogeneous and has an unchangeable composition
Mixture = a system made up of two or more substances
Ionic or Molecular compound?
- Metal + Non-metal
Ionic Compound
Write the chemical formula resulting from the combination of the following ions.
1) NH4+ SO42-
2) Ca2+ OH-
(NH4)2SO4
Ca(OH)2
What is the correct name for each of the following ionic compounds:
1) Silver Chloride
2) Sodium Oxide
AgCl2
Na2O
What is the difference between an atom and an ion?
Ion contains an electrical charge, atoms do not.
Atom = smallest possible unit of an element
Ion = atom or molecule that contains an electrical charge (+/-)
State three things that distinguish a pure substance from a mixture (consider its nature, physical properties, composition, etc.)
1) pure substances have unchanging, uniform physical properties
2) mixtures can have changeable composition
3) In heterogenous mixtures, each component present has different physical properties
What type of chemical bonding do molecular compounds have?
Covalent bonding (sharing electrons)
What is the chemical formula for Copper (II) sulphate pentahydrate
CuSO4·5H2O
What is the correct name for the following molecular compounds?
1) N2O
2) I2O5
1) Nitrous oxide
2) Iodine pentoxide
What is water considered?
a) atom
b) molecule
c) ion
d) none of the above
b) molecule (H2O)
molecule = cluster of two or more atoms held together by strong electrical forces
What is the difference between a homogeneous mixture vs. a heterogeneous mixture?
Homogeneous mixtures have a uniform composition throughout, appearing as a single phase (e.g. brass)
Heterogeneous mixtures have non-uniform, visibly distinct phases or regions (e.g. salad dressing)
A newly discovered compound was tested and found to have the following characteristics:
- high melting point
- solid at room temperature
Is the compound ionic or molecular?
Ionic Compound
Write the formula for the following compounds:
- tungsten (V) bromide
- mercury (II) acetate
tungsten (V) bromide: WBr5
Mercury (II) acetate: Hg(CH3COO)2
What is the correct name for the following ionic hydrate:
Ba(HS)2·4H2O
Barium hydrosulfide tetrahydrate
What is the difference between an element vs. a compound? Provide an example of an element and a compound.
Element is made up of one type of atom, Compound is made up of different types of atoms
One possible answer:
element: Hydrogen (H)
compound: Sodium Chloride (NaCl)
Determine which are pure substances or mixtures:
a) sugar
b) dirt
c) air
Pure substance: sugar (compound)
Mixture: dirt (heterogeneous), air (homogeneous)
True or false: Molecular compounds conduct electricity in any state.
False. Molecular compounds do NOT conduct electricity.
What is the formula for Chromic Acid?
H2CrO4
True or False: the correct formula for Iron (III) sulphate nonahydrate is Fe3(SO4)2·9H2O
False. The correct formula is Fe2(SO4)3·9H2O
A student is given a sample of matter with the following properties:
It has a uniform composition throughout.
It cannot be separated by physical methods.
When tested, it is found to contain two different elements chemically bonded in a fixed ratio.
It can only be broken down using chemical reactions.
What type of matter is the sample?
Compound
You've been given a bottle of gravel and you've been asked to separate the gravel into its component parts.
What type of matter is gravel, and what separation method should you use?
Gravel: mechanical mixture (heterogeneous mixture)
Separation method: filtration
NaCl
CO₂
MgO
CH₄
CaF₂
Classify each compound as ionic or molecular.
Ionic: NaCl, MgO, CaF2
Molecular: CO2, CH4
What is the formula of Manganese(IV) monohydrogen phosphate?
Mn(HPO4)2
A compound has the formula Fe₂O₃.
Answer the following:
Chemical Name
Ionic or molecular compound?
The ion charges
Iron (III) Oxide
Ionic
Fe3+ O2-