Are You Ready? Page 2
1.
a) physical, quantitative

b) physical, quantitative

c) physical, qualitative

d) chemical

e)  chemical
2.
a)  physical - water is changing state from liquid to gas

b)  chemical - propane reacts with oxygen in the air to produce carbon dioxide and water

c)  chemical - iron oxide was produced

d)  chemical - The sugars in the apple have reacted with the oxygen in the air to produce new and different molecules which are brown in colour.

e)  physical - if the tea is evaporated we get the sugar back

f)  chemical - the egg proteins have denatured with the heat and taken on new shapes

g)  physical - the butter has just changed state from solid and liquid

h)  chemical - the wood molecules react with the oxygen in the air to produce carbon dioxide and water

i)  physical - the copper molecules have changed position, nothing else has taken place

j)   chemical - the vaporized candle molecules have burned to produce carbon dioxide and water

k)   physical - the water molecules in snow melt from solid to liquid, a change of state
3.  
a)  malleability

b)  conductivity

c)   density

d)   melting point

e)   hardness
4.
a)  An element is considered to be the a group of atoms of all the same type.  A compound is considered to be a grouping of molecules of all the same type.   Examples of elements are Gold, Silver, Iron, Chlorine gas, while examples of compounds are water, NaCl, CO2 and NH4NO3

b)  The solute is the substance that dissolves when a solution is created while the solvent is the substance that does the dissolving.  The solute makes up the smaller percentage of the solution while the solvent makes up the larger percentage.  In a solution of salt water the salt makes up the solute and the water makes up the solvent.

c)  A mechanical mixture is a mixture that has distinct phases that can be seen after mixing.  A example would be a mixture of salt, sand and sawdust.  Even after mixing the three substances can be seen clearly.  A solution is a mixture in which one substance disappears and so the entire solution displays only 1 phase.  An example is sugar and water.    Once the sugar is dissolved the solution shows only the water phase.

d)   A homogeneous mixture is one that displays only one phase, examples being sugar and water, milk,  and cough syrup.   A heterogeneous  mixture is one in which two or more phases can be seen after mixing has taken place.

e)   A proton is a positively charged sub atomic particle found in the nucleus of an atom.  The neutron is a neutral particle also found in the nucleus of the atom.

f)   A metal is usually a solid with silvery-greyish colours (the exceptions are gold and silver) which are malleable, good conductors of heat and electricity.   A non-metal  can be a brittle solid,  gas or liquid and  they are poor conductors of heat and electricity

g)  A atom is a lone particle of an element.  A molecule is the smallest part of a compound.

h)  The atomic number (Z) is the number of protons in the nucleus and the number of electrons in orbit in an atom.  The mass number (A) is a mathematical sum of the protons and neutrons in the nucleus..

i)   A pure substance can be either an element or compound that is made up of 100% with nothing else added to it.  i.e. Pure gold must have no atoms other than gold in the sample.    A mixture is something that has more than one type of atom or compound mixed together.
5.
a)  element - All the molecules are made from identical atoms.  This could be hydrogen, fluorine, chlorine, oxygen or nitrogen.

b)  compound - All the molecules are identical.

c)  compound - All the molecules are identical

d)  mixture - There are two different types of  in this diagram. The green atoms represent a monoatomic element like one of the noble gases and the purple compound  is a diatomic molecule of the element like  hydrogen.

e)  mixture - two different diatomic elements

f)   mixture - two diatomic elements and one compound

g)   mixture - one diatomic element and two different compounds

h)   mixture - a monatomic atom and a compound
6.
Particle
Relative Mass
Relative Charge
Location Within Atom
proton
1
+1
in nucleus
electron
1/1867 or 0
-1
in orbit around the nucleus
neutron
1
0
in nucleus

7.
a)   halogens - fluorine, chlorine, bromine, iodine, astatine

b)   alkali metals - hydrogen, lithium, sodium, potassium, rubidium, cesium, francium

c)   noble gases - helium, neon, argon, krypton, xenon, radon

d)   alkaline earth metals -  beryllium, magnesium, calcium, strontium, barium, radium
8.
Chemical name
Chemical symbol
Atomic number
Number of protons
Number of neutrons
Mass Number
Number of electrons
helium
He
2
2
2
4
2
sulphur
S
16
16
16
32
16
oxygen
O
8
8
8
16
8
neon
Ne
10
10
10
20
10
potassium
K
19
10
20
39
19

9.
a)  calcium

b)  oxygen

c)  sodium

d)  chlorine
10.
a)  magnesium

b)  boron

c)  helium

d)  potassium

e)  oxygen
11
a)  The elements in column A are metals

b)  The elements in column B are non-metals

c)   calcium oxide, CaO; potassium fluoride, KF; aluminium nitride, AlN
12
a)   The individual components of this mixture can be separated from each other by using knowledge of their different physical properties.  Sand and iron filings are solid; whereas rubbing alcohol and water are both liquids.  This mixture can be passed through filter paper.  The sand and iron filings will remain in the filter paper, and the alcohol-water mixture will pass through it.  The water that remains mixed with the sand and iron filings will eventually evaporate.  Since iron filings are magnetic, where as sand is not, the iron filings can be separated from the sand using a magnet.  For the liquid components, the alcohol has a lower boiling point so the mixture can be heated and the alcohol will evaporate out of the mixture first leaving behind the water.

b)    mixture, magnet, paper towel, filter paper, large beaker, distillation apparatus, funnel, iron clamp, retort stand, Bunsen burner, 10-mL graduated cylinder, round-bottomed flask

c)    Procedure
Part A: Removal of Sand and Iron Filings from Liquid
    1.  Pour the mixture through the filter paper. Collect the liquid flowing through the filter paper into a large beaker.  
     2.  Remove the sand and iron filings from the filter paper onto a paper towel.
     3.  Pour the collected liquid through the filter paper a second time.  Collect any additional sand and iron filings caught in the filter paper and add it to the pile on the paper towel.  Allow the pile to dry.

Part B: Removal of Iron Filings
     4.   Use a baggy covered magnet to collect the iron filings from the pile of sand and iron filings on the paper towel.
      5.   Pull the baggy off the magnet, dropping the iron filings onto a clean paper towel.
      6.   Repeat until all the iron filings are removed from the sand.

Part C:  Separation of the Alcohol and Water
      7.   Pour the liquid from the large beaker into a round-bottomed flask
      8.   After setting up the distillation apparatus, turn the water on to fill the condenser tube.
      9.   Light the bunsen burner and place it under the round-bottomed flask
    10.   When the temperature reaches approximately 78oC, the alcohol will start to boil.  At this temperature, the distillate is alcohol.
     11.   Collect the distillate at the end of the condenser tube into a 10 mL graduated flask.
     12.   Stop collecting the distillate when the temperature has reached 82oC
   
13.
Distribute the gas into three tubes. To determine whether the gas is hydrogen, invert the first tube and place a burning splint just inside its mouth.  If you hear a popping sound, the gas is hydrogen.  To determine whether the gas is oxygen, invert the second tube and place a glowing splint just inside its mouth.  If the splint ignites, the gas is oxygen.  To determine whether the gas is carbon dioxide, pour limewater into the third test tube.  Shake well.  If a white precipitate forms, the gas is carbon dioxide.
14.
a)   This action is unsafe.  The student may cut herself with the broken glass through the paper towel.  the broken glass may be coated with toxic or corrosive chemicals.  Also, the student may not be able to collect all the pieces of broken glass with a paper towel, leaving behind an unsafe work area for other students.  The student should have obtained a brush and a dustpan from the teacher to collect the broken glass.  The broken glass should have been placed in the container designated "Broken Glass" in the classroom.

b)   This action is unsafe.  Rubbing one's eyes does not remove the chemical, but further distributes it and allows it to be further absorbed by the eye, resulting in more irritation and damage.  The student should have proceeded immediately to the eye wash station and flushed the eye with water for 10-15 minutes.

c)   This action is safe.

d)   This action is unsafe.  The substances ingested may be poisonous.  No chemicals should ever be ingested in a chemistry laboratory.
15
a)   compressed gas

b)   flammable and combustible materials

c)   corrosive materials