What are two examples of metals provided in the text?
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Aluminium (Al) and Magnesium (Mg)
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What are two examples of metals provided in the text?
Aluminium (Al) and Magnesium (Mg)
What are two examples of non-metals provided in the text?
Nitrogen (N) and Oxygen (O)
What are two examples of metalloids (semi-metals) provided in the text?
Silicon (Si) and Boron (B)
How is the physical appearance of a metal described?
Shiny
How is the physical appearance of a non-metal described?
Dull
What is the characteristic melting and boiling point of metals?
High (typically solids)
In terms of shape-changing properties, what are two characteristics of metals?
Malleable and ductile
How do metals compare to non-metals regarding electrical and heat conductivity?
Good conductors of heat and electricity
Where do the properties of metalloids fall relative to metals and non-metals?
Between metals and non-metals
Aside from appearance and conductivity, name two physical properties that differentiate metals from non-metals.
Hardness (metals are hard, non-metals are soft) and Density (metals have high density, non-metals have low density).
What extraction method is used for very unreactive metals like gold (Au) and platinum (Pt)?
Physical methods (e.g., gold panning)
How are unreactive metals such as mercury and silver extracted from their ores?
Heating the ore alone
What chemical method is used to extract moderately reactive metals like iron?
Heating the ore with carbon
How are highly reactive metals such as magnesium and aluminum extracted?
Electrolysis of molten ores
Name two very unreactive metals that can be extracted using physical methods.
Gold (Au) and Platinum (Pt)
Which moderately reactive metal is extracted by heating its ore with carbon?
Iron (Fe)
Which two reactive metals are extracted via electrolysis of their molten ores?
Magnesium (Mg) and Aluminum (Al)
Which two unreactive metals can be extracted by simply heating their ores alone?
Mercury (Hg) and Silver (Ag)
Provide an example of a physical method used to collect gold from the environment.
Gold panning
What sub-atomic particles are found inside the nucleus of an atom?
Protons and neutrons
What is the name of the area surrounding the nucleus where electrons move?
Electron cloud
What is the symbol, relative charge, relative mass, and position of a proton?
(p), (+1), 1, inside the nucleus
What is the symbol, relative charge, relative mass, and position of a neutron?
(n), 0, 1, inside the nucleus
What is the symbol, relative charge, relative mass, and position of an electron?
(e^-), (-1), (1/1836), move around the nucleus
Which sub-atomic particles have a relative mass of 1, and which has a relative mass of (1/1836)?
Proton and neutron ((1)) vs electron ((1/1836))
Which two sub-atomic particles have opposite relative charges?
Proton (+1) and electron (-1)
Which sub-atomic particle has no relative charge?
Neutron (0)
Where is the majority of an atom's mass concentrated, based on the location of protons and neutrons?
Nucleus
Which sub-atomic particle is found moving outside the nucleus?
Electron
List three common forms of calcium carbonate (CaCO(_{3})).
Chalk, Limestone, and Marble
What are the products of heating calcium carbonate?
Calcium oxide (CaO) and Carbon dioxide (CO(_{2}))
What is the common name for calcium oxide (CaO)?
Quicklime
What is formed when calcium oxide (quicklime) reacts with water?
Calcium hydroxide [Ca(OH)(_{2})]
What is calcium hydroxide [Ca(OH)(_{2})] called when only a small amount of water is added?
Slaked lime
What is the term for a solution of calcium hydroxide when a lot of water is added?
Lime water
What products are formed when calcium hydroxide reacts with carbon dioxide?
Calcium carbonate (CaCO({3})) and water (H({2})O)
What happens to lime water (calcium hydroxide) when carbon dioxide is bubbled through it?
It turns milky.
What chemical is formed when calcium carbonate reacts with excess water and carbon dioxide?
Calcium hydrogencarbonate (Ca(HCO({3}))({2}))
What visual change occurs when calcium carbonate reacts with excess water and carbon dioxide?
The solution turns colorless.
Write the balanced chemical equation for the thermal decomposition of calcium carbonate.
(CaCO_{3} \rightarrow CaO + CO_{2})
Write the chemical equation for the reaction between calcium oxide and water.
(CaO + H_{2}O \rightarrow Ca(OH)_{2})
Write the chemical equation representing the lime water test for carbon dioxide.
(Ca(OH){2} + CO{2} \rightarrow CaCO_{3} + H_{2}O)
Write the chemical equation for the formation of calcium hydrogencarbonate from calcium carbonate.
(CaCO_{3} + H_{2}O + CO_{2} \rightarrow Ca(HCO_{3})_{2})
What does the atomic number of an element represent?
The number of protons ((p)) in an atom.
What does the mass number of an atom represent?
The sum of the number of protons and the number of neutrons ((p + n)) in an atom.
Which two sub-atomic particles have an equal number in a neutral atom?
Protons ((p)) and electrons ((e^-))
Why are all atoms considered neutral? (Provide two points)
The relative charge of a proton and an electron are (+1) and (-1), and their numbers in an atom are equal.
What are the relative charges of a proton and an electron, respectively?
(+1) for a proton, (-1) for an electron.
If an atom's atomic number is known, which specific sub-atomic particle count does this directly provide?
Protons ((p))
What particle count is added to the proton count to calculate the mass number?
Neutrons ((n))
What products are formed when calcium carbonate reacts with dilute hydrochloric acid?
Calcium chloride, water, and carbon dioxide.
What is the primary observation when dilute hydrochloric acid is added to calcium carbonate?
Effervescence (bubbling) occurs.
Write the chemical equation for the reaction of calcium carbonate with dilute hydrochloric acid.
(CaCO_{3} + 2HCl \rightarrow CaCl_{2} + H_{2}O + CO_{2}) (note: balanced)
What simple chemical test is used to identify the presence of a carbonate (like calcium carbonate)?
Addition of dilute hydrochloric acid and observation of effervescence (bubbles).
What is the definition of an isotope?
Different atoms of the same element with the same number of protons but different number of neutrons.
How do isotopes of the same element differ in terms of physical properties?
Isotopes have different physical properties.
How do isotopes of the same element compare in terms of chemical properties?
Isotopes have the same chemical properties.
What is the definition of Relative Atomic Mass (RAM)?
The weighted average mass of the relative isotopic masses of all naturally occurring isotopes of an element.
On what scale is the relative atomic mass (RAM) measured?
(^{12}C = 12.00) scale.
How is the relative atomic mass (RAM) of chlorine calculated based on its isotopes (35) (75%) and (37) (25%)?
(35 \times 75% + 37 \times 25% = 35.5)
Is RAM a simple average or a weighted average of isotopic masses?
Weighted average mass.
According to the unit overview, what are the two primary components that make up a solution?
Solute and solvent
In the context of sea water, which substance acts as the solvent?
Water
In sea water, what substances act as the solutes?
Several salts (e.g., NaCl)
What are the three types of solutions mentioned in the Unit 3 overview?
Dilute solution, concentrated solution, and saturated solution.
What type of solution is formed when a solution can no longer hold any more solute at a given temperature?
A saturated solution.
How does increasing the temperature of a solvent typically affect the solubility of a solute?
Solubility increases as the temperature of the solvent increases.
What is an electron shell defined as?
The position of electrons within an atom.
How many electrons are shown surrounding the 'H' symbol in the hydrogen atom diagram?
Two 'x' symbols (representing 2 electrons in the diagram).
How many electrons are shown surrounding the 'O' symbol in the oxygen atom diagram?
6 'X' symbols (representing 6 electrons in the diagram).
Which separation method is described as a quick way to separate a much denser insoluble solid from a liquid?
Decantation
What is the primary purpose of using the decantation method?
To obtain a clear liquid or remove unwanted liquid.
Which piece of equipment is used in decantation to help guide the liquid into another beaker?
A glass rod.
What type of material is primarily removed from a mixture through the process of filtration?
Insoluble solids (like clay).
Can the process of filtration be used to remove bacteria or microorganisms from sea water?
No, it cannot remove bacteria or microorganisms.
What is the term for the liquid that has passed through the filter funnel during filtration?
Filtrate
What is the term for the solid material trapped in the filter paper during filtration?
Residue
How is evaporation defined in the context of ocean solution separation?
The conversion of a liquid to vapor at any temperature below its boiling point.
What is specifically collected during the evaporation of sea water?
Common salt (solute).
According to the diagram, what are the four key pieces of equipment used in an evaporation setup?
Bunsen burner, tripod, wire gauze, and an evaporating dish.
What is the definition of crystallization?
The process of forming solid crystals when a solution can no longer hold the solute.
What are the two primary methods listed for achieving crystallization?
Cooling a hot saturated solution and slow evaporation at room temperature.
Describe the process by which crystals form during slow evaporation at room temperature.
The solution's concentration increases as the solvent evaporates, eventually reaching saturation and forming crystals.
How can one test whether a solution is saturated according to the "Test for saturated solution" description?
Place a drop on a cool microscope slide with a glass rod and observe if crystals form quickly.
What are the three main natural resources identified in Unit 2?
What is the percentage of nitrogen ((N_2)) in the air?
78%
What is the percentage of oxygen ((O_2)) in the air?
21%
What is the percentage of carbon dioxide ((CO_2)) in the air?
0.04%
Which term describes a pure substance that cannot be broken down into anything simpler by chemical methods?
Element
Which term describes a pure substance consisting of two or more elements chemically joined together?
Compound
Which term describes a substance made up of two or more substances that are not chemically joined together?
Mixture
Which two gases make up the vast majority (approximately 99%) of the air?
Nitrogen ((N_2)) and Oxygen ((O_2))
According to the notes, what are the two defining characteristics of matter?
It occupies space and has mass.
According to the notes, can matter be created or destroyed?
No, it cannot be created or destroyed.
What is the definition of a physical change?
A change in which no new substance is formed.
What is the definition of a chemical change?
A change in which one or more new substances are formed.
What is the example of a physical change provided in the notes?
Centrifugation (Centrifragation)
What is the example of a chemical change provided in the notes?
Photosynthesis
What is the definition of a physical property?
A property that can be measured without changing the composition of the substance.
What is the definition of a chemical property?
A property that describes a substance's ability to form new substances.
List five examples of physical properties mentioned in the notes.
What is the primary objective of simple distillation when used on sea water?
To obtain water (H₂O) from a solution.
In the process of distillation, what is the term for the pure water collected at the end?
Distillate
Where does the steam condense back into liquid water during simple distillation?
The steam condenses in the inner tube of the water-cooled condenser.
What is the purpose of adding anti-bumping granules during the distillation process?
To prevent overflow from boiling.
At what temperature does water boil to turn into steam in the distillation setup?
100°C
What is the chemical formula for the Iron (II) ion?
(Fe^{2+})
What is the characteristic color of the Iron (II) ion in solution?
Pale green
What color is associated with the Iron (III) ((Fe^{3+})) ion?
Yellow
What is the color of the Copper (II) ((Cu^{2+})) ion?
Blue
What is the chemical formula for the Permanganate ion?
(MnO_4^-)
What is the color of the Permanganate ion ((MnO_4^-))?
Purple
What is the characteristic color of the Dichromate ion ((Cr_2O_7^{2-}))?
Orange
What color are Chromium (III) ((Cr^{3+})) and Nickel (II) ((Ni^{2+})) ions?
Green
What color is the Manganese (II) ((Mn^{2+})) ion?
Very pale pink
What is the chemical formula for the Ammonium ion?
(NH_4^+)
What is the chemical formula for the Carbonate ion?
(CO_3^{2-})
What is the chemical formula for the Dichromate ion?
(Cr_2O_7^{2-})
In an ion migration experiment, why does the purple spot of Permanganate ions move towards the positive electrode?
Towards the positive electrode (anode) because they are negatively charged.
What is the formula for the Phosphate ion?
(PO_4^{3-})
What are two common polyatomic 1- anions that contain hydrogen?
Hydrogencarbonate ion ((HCO_3^-)) and Hydrogensulphate ion ((HSO_4^-))
In the periodic table, what is the term for a horizontal row of elements?
A period
In the periodic table, what is the term for a vertical column of elements?
A group
What do all elements in the same period of the periodic table have in common?
The number of occupied electron shells
What do all elements in the same group of the periodic table have in common?
The number of electrons in the outermost shell (valence electrons)
As you move from left to right across a period, which property of elements consistently increases?
Atomic number (number of protons)
What is the general trend in the type of element (e.g., metal, non-metal) when moving from left to right across a period?
Metals → Metalloids → Non-metals
What are the chemical formulas for the Nitrite and Nitrate ions respectively?
(NO_2^-) and (NO_3^-)
What are the chemical formulas for the Sulphite and Sulphate ions respectively?
(SO_3^{2-}) and (SO_4^{2-})
What is the chemical formula for the Hydroxide ion?
(OH^-)
What type of wire is used to perform a flame test due to its high melting and boiling points?
Nichrome wire.
What should the nichrome wire be dipped into before taking a sample for a flame test?
Concentrated hydrochloric acid (conc. HCl).
Under which type of flame should the nichrome wire with the solid sample be held to observe its color?
Non-luminous flame.
What color is observed in a flame test for Potassium?
Lilac
What color is observed in a flame test for Calcium?
Brick-red
What color is observed in a flame test for Sodium?
Golden yellow
What color is observed in a flame test for Copper?
Bluish green
What are the steps for testing for the presence of chloride in a sample?
Dissolve the sample in water, add excess dilute nitric acid, and then add silver nitrate solution.
What observation confirms the presence of chloride in the chloride test?
A white precipitate forms.
How does the composition of a mixture compare to that of a compound?
Mixture: Variable composition. Compound: Definite composition.
Compare the energy changes involved when a mixture is formed versus when a compound is formed.
Mixture: No energy change when formed. Compound: There is an energy change during formation.
Compare the properties of the constituents in a mixture to those of the elements in a compound.
Mixture: Constituents retain their original properties. Compound: Properties are different from the constituent elements.
How do the separation methods for mixtures and compounds differ?
Mixture: Can be separated by physical methods. Compound: Can only be separated by chemical methods.
What are the physical appearance and magnetic properties of Iron(II) sulphide?
It is a dark brown solid that is not attracted to a magnet.
What happens when dilute hydrochloric acid ((HCl)) is added to Iron(II) sulphide?
A gas with a bad egg smell is produced.
What are the physical appearance and magnetic properties of a mixture of iron and sulphur?
It is a yellowish black powder where only the iron is attracted to a magnet.
What happens when dilute hydrochloric acid ((HCl)) is added to a mixture of iron and sulphur?
Hydrogen gas is produced.
List the metal reactivity series from most reactive to least reactive as per the provided notes.
Potassium (K) (>) Sodium (Na) (>) Calcium (Ca) (>) Magnesium (Mg) (>) Aluminium (Al) (>) Zinc (Zn) (>) Iron (Fe) (>) Lead (Pb) (>) Copper (Cu) (>) Mercury (Hg) (>) Silver (Ag) (>) Gold (Au)
What are the observations (flame color and oxide color) when Potassium (K) reacts with oxygen?
Lilac flame; white oxide layer.
What are the observations (flame color and oxide color) when Sodium (Na) reacts with oxygen?
Golden yellow flame; white oxide.
What are the observations (flame color and oxide color) when Calcium (Ca) reacts with oxygen?
Brick red flame; white oxide.
What are the observations (flame color and oxide color) when Magnesium (Mg) reacts with oxygen?
Bright white flame; white oxide.
What is the color of the oxide formed when Aluminium (Al) reacts with oxygen?
White (oxide).
Describe the color change of Zinc oxide (Zn oxide) during and after heating with oxygen.
The oxide is white when cold and yellow when hot.
What is the color of the oxide formed when Iron (Fe) or Copper (Cu) reacts with oxygen?
Black (oxide).
What is the color of the oxide formed when Lead (Pb) reacts with oxygen?
Yellow (oxide).
What is the color of the oxide formed when Mercury (Hg) reacts with oxygen?
Red (oxide).
Which three metals show no reaction when heated with oxygen according to the notes?
Silver (Ag), Platinum (Pt), and Gold (Au).
Generally, what is the product when a metal reacts with oxygen?
Metal oxide.
What is the common name for the elements in Group I of the periodic table?
Alkali metals
What is the trend in reactivity for Group I (Alkali metals) as you move down the group?
Reactivity increases as you go down the group.
How are Alkali metals typically stored and why?
Paraffin oil (to prevent reaction with oxygen)
What is the appearance of a freshly cut Group I metal?
Shiny, silvery-white solid (when freshly cut)
Which three Group I metals are less dense than water and will float on its surface?
Lithium, Sodium, and Potassium (Li, Na, K)
What is the trend for melting point and boiling point as you go down Group I (Alkali metals)?
They decrease.
What happens to the appearance of a Group I metal when it reacts with oxygen?
They tarnish rapidly.
What two products are formed when a Group I metal reacts with water?
Metal hydroxides and hydrogen gas
What happens to the pH of the resulting solution when an Alkali metal reacts with water?
It becomes alkaline (pH increases).
What substances are formed when Group I elements react with chlorine?
Chlorides (salts)
Between which two types of elements is an ionic bond generally formed?
Metals and Non-metals
What process leads to the formation of an ionic bond?
The transfer of one or more electrons from one atom to another.
What is the primary objective for atoms when losing or gaining electrons to form ions?
To obtain the stable electronic configuration of a noble gas.
What is the name for the regular, packed arrangement of ions in a giant ionic compound?
A lattice.
What specific forces hold giant ionic structures together?
Electrostatic forces of attraction.
What are two mechanical properties of giant ionic compounds mentioned in the text?
Hard and brittle.
Due to strong ionic bonds, what type of melting and boiling points do ionic compounds possess?
High melting and boiling points.
In which type of substance are ionic compounds generally soluble?
Water.
Under what conditions can ionic compounds conduct electricity?
When in a molten (liquid) or dissolved state.
In what state do ionic compounds NOT conduct electricity?
Solid.
Why are dust, water, and carbon dioxide ((CO_2)) removed during the purification of air for fractional distillation?
To prevent the formation of dry ice and ice, which would block the pipes.
How is air liquefied during fractional distillation?
High pressure is used to compress the air up to (-200^\circ\text{C}).
What is the relationship between the liquefaction temperature and the boiling and melting points of the air components?
Lower than the boiling point and higher than the melting point.
In a fractionating column for air, how does the temperature change from the bottom to the top?
The temperature decreases from the bottom to the top (cooler at the top).
What are the boiling points of nitrogen, argon, and oxygen?
Nitrogen ((N_2)): (-196^\circ\text{C}) Argon ((Ar)): (-186^\circ\text{C}) Oxygen ((O_2)): (-183^\circ\text{C})
Which component of air, having the lowest boiling point, boils first and is collected as a gas at the top of the fractionating column?
Nitrogen ((N_2))
What happens to oxygen in the fractionating column compared to nitrogen?
Oxygen ((O_2)) remains as a liquid in the lower part because its boiling point is higher.
On what physical principle does the separation of the mixture of gases in air by fractional distillation depend?
It depends on the fact that different components of air have different boiling points.
What is the word equation for the reaction between Lithium and water?
Lithium + water → Lithium hydroxide + hydrogen
What is the word equation for the reaction between Sodium and water?
Sodium + water → Sodium hydroxide + hydrogen
What is the word equation for the reaction between Potassium and water?
Potassium + water → Potassium hydroxide + hydrogen
What observation is made when a piece of Lithium reacts with water?
It fizzes steadily on the water's surface.
What observation is made when a piece of Sodium reacts with water?
It melts into a silvery ball and fizzes quickly.
What observation is made when a piece of Potassium reacts with water?
It melts into a silvery ball and fizzes furiously.
What specific event occurs when Potassium reacts with water that does not typically occur with Lithium or Sodium?
The hydrogen gas catches fire and burns with a lilac flame.
What are the products of the reaction between a reactive metal (e.g., K, Na, Ca) and cold water?
Metal hydroxide and Hydrogen gas
What are the products of the reaction between a metal (e.g., Mg, Al, Zn, Fe) and steam?
Metal oxide and Hydrogen gas
Describe the observations when Potassium (K) reacts with cold water.
Moves around on the water surface and produces a lilac flame.
Describe the observations when Sodium (Na) reacts with cold water.
Melts to form a silvery ball and produces a golden yellow flame.
What is the specific observation mentioned for Calcium (Ca) reacting with cold water?
Produces a hissing sound.
What is the observation for Magnesium (Mg) reacting with steam?
The surface of the metal changes from silvery to white.
