Flashcards in Topic 2.1 - 2.4 Deck (77):
Mnemonic to remember Reactivity Series of Metals?
Please Send Little Charlie's Monkeys and Zebras In Tall Lead Cages Securely Guarded
How do Potassium and Sodium react when cut and left in air?
Shiny surface quickly tarnishes
How does Potassium react when heated in air?
Burn with lilac flame
How does Sodium react when heated in air?
Burns with bright yellow flame
How do Ca, Mg, Al and Zn react when left in air?
React slowly forming layer of oxide
How does Calcium react when heated in air?
Burns with brick red flame
How does Magnesium react when heated in air?
Burns with bright white light, leaving white ash
How does Aluminium powder react when heated in air?
Burns with white sparks leaving white solid
How does Zinc react when heated in air?
Burns leaving yellow solid, which changes to white when cooled
How do Iron and Copper react when left in air?
Forms oxide layer, easily rubbed off
How does Iron wool react when heated in air?
Burn with yellow/orange sparks forming black solid
How does Copper react when heated in air?
Quickly forms black oxide layer
Give 4 observations of Potassium reacting with water?
Fizzes across surface
Bubbles of gas
Give 4 observations of Sodium reacting with water?
Fizzes across surface
Rolls in to ball
Give 3 observations of Calcium reacting with water?
Bubbles of gas
Give observation of Magnesium reacting with water?
Some bubbles of gas released
Will Aluminium, Zinc, Iron and Copper react with water?
If Universal indicator was used, what would the colour change be after the reactions of Potassium and Sodium in water?
Green to Blue
How do we know that the gas produced from reactions of Calcium and Magnesium with water is Hydrogen?
When gas is collected, it burns with a squeaky pop
Word Equation for reaction of Metal and Water?
Metal + Water ---> Metal Hydroxide + Hydrogen
Magnesium reaction with steam?
Produces bright white light and forms white solid
Reaction of Aluminium powder and steam?
Forms white powder
Reaction of Zinc with Steam?
Glows, producing yellow powder which becomes white when left to cool
Reaction of Red hot Iron and steam?
Forms black solid
What is a Displacement Reaction?
This is a reaction where a more reactive metal displaces a less reactive element from its compound
Give 2 tests for presence of water?
- Placing Anhydrous Copper Sulphate, if colour changes from white to blue, water is present
- Placing Anhydrous Cobalt Chloride, if colour changes from blue to pink, water is present
How to test for pure water?
Check if freezing point is exactly 0°C or if boiling point is exactly 100°C
Definition of Hardwater?
Water that doesn't easily lather with soap
Name 2 ions that cause water to be hard?
Why does Hard water not lather easily with soap?
Calcium ions react with Stearate ions in soap to form scum
Chemical name of Scum?
What ion in hard water helps form strong teeth and bones?
Give 2 terms that describe hardness of hard water?
What 2 salts causes Hardwater to be Temporary?
Give 3 features of Hard Water areas?
Stalagmites and Stalactites
Definition of Temporary Hardwater?
Water that when boiled, Calcium HydrogenCarbonate decomposes and insoluble Calcium Carbonate is formed
What is Calcium Carbonate?
Give word equation of formation of scum?
Sodium Stearate + Hardwater ---> Calcium Stearate + Sodium
Give word equation of temporary Hardwater being heated?
Calcium HydrogenCarbonate ---> Carbon Dioxide + Water + Calcium Carbonate
Why does boiling temporary hard water cause it to become soft?
Boiling the water causes precipitation of Calcium/Magnesium Carbonate. This removes calcium and magnesium ions, removing the hardness
Definition of Permanent Hardwater?
Water that contains Calcium and Magnesium salts that cannot be broken down by boiling
Give 2 ways in which Permanent Hardwater can become soft?
- Adding Washing Soda
- Ion Exchange Columns
Why does adding washing soda to Hardwater cause it to become soft?
Washing soda is Sodium Carbonate. Calcium and Magnesium ions react with Sodium Carbonate and form insoluble Calcium/Magnesium Carbonate, removing the hardness
Why do Ion Exchange columns make Hardwater soft?
Ion exchange column contains resin with sodium ions. Calcium and Magnesium ions exchange with Sodium as water flows through column. Calcium and Magnesium ions are thus removed, removing the hardness
Give 4 advantages of Hardwater?
Provides calcium ions for strong bones and teeth
Better for tanning leather
Better for brewing beer
Give 3 disadvantages of Hardwater?
Produces scum which wastes soap
Special dishwasher salt needed so as to soften water, extra cost
Give 2 examples of Dessicants?
A substance which absorbs moisture
A substance that absorbs so much moisture in the air that it dissolves, forming a solution
Give 3 advantages of Flouridation?
Prevents tooth decay
Lowers cavities in teeth
Give 2 disadvantages of Flouridation?
Ethical issues, seen as mass medication
What is Flouridation?
When flouride ions are added to the water supply
Give 4 signs that indicate a chemical reaction taking place?
Give 3 exothermic reactions?
Give 3 endothermic reactions?
Define Thermal Decomposition?
The breaking down of a compound using Heat
Give 2 uses of limestone?
Neutralising acidic soil
Give 2 uses of Calcium Oxide?
- Mixing with water to produce limewater
- Making plaster
3 advantages of Limestone quarrying?
Raw material for use in blast furnace or soil neutralisation
Boosts the economy
Give 3 disadvantages of Limestone quarrying?
Ruins animal habitats
Noise and dust pollution
Give 3 consequences in Global Warming?
Destruction of habitat
Who devised the Continental Drift Theory?
What is Continental Drift?
The idea that the continents were once 1 large landmass, but they drifted apart
What is the current theory on plate tectonics?
Continents move due to conventional currents in the mantle
What causes an Earthquake?
When 2 tectonic plates slide past each other, or 1 slides under another, the plates may bend. As a result forces can be suddenly released which causes to ground to shake violently
What causes a Volcano?
When plates move apart, the earths crust is stretched, and may even crack. Molten magma can thus escape and a volcano is formed
What is the chemical name of Rust?
Hydrated Iron(III) Oxide
A process that bonds a layer of reactive metal over the surface of a less reactive metal
Define Reducing Agent?
A substance that reduces an oxidised compound
Define Oxidising Agent?
A substance which oxidises a reduced compound
Give 3 examples of Oxidation and Reduction in Industry?
- Extraction of iron from blast furnace
- Extraction of aluminium by electrolysis
- Production of ammonia in the Haber Process
Define Rate of Reaction?
A measure of how fast or slow a reaction is
2 ways to measure Rate of Reaction?
- Measure how quickly the products form in a given time
- Meausre how quickly reactants are used up in a given time
Time is Inversely Proportional to Rate. True or false?
What 4 factors affect rate of reaction?
What is Collision Theory?
For a reaction to take place, reacting particles must collide with sufficient Activation Energy