C5- Chemical changes ⚗️ Flashcards
What happens when a metal reacts with oxygen ?
- when a metal reacts with oxygen, it forms a metal oxide and a oxidation reaction takes place.
What is a oxidation
- Oxidation is a reaction that involves gaining oxygen.
- [oxidation is the loss of electrons; the gain of oxygen]
What does OIL RIG stand for ?
- oxidation is, loss of electrons and gain of oxygen.
- reduction is, gain of electrons and loss of oxygen.
What is reduction ?
- reduction is a reaction involving the loss of oxygen.
- [reduction is the gain of electrons]
What is the mnemonic for remembering the reactivity series ?
- Please- potassium
- Stop- sodium
- Lazily- lithium
- Calling- calcium
- Me- magnesium
- A- aluminium
- Careless- carbon
- Zebra- zinc
- Instead- iron
- Try- tin
- Learn- lead
- How- hydrogen
- Copper
- Saves- silver
- Gold
How does: pottasium, sodium and lithium react with water ?
Hint: at room temperature
- potassium, sodium and lithium will react very rapidly with water, at room temperature.
How does: pottasium, sodium and lithium react with acids ?
- potassium, sodium and lithium react dangerously fast with acids.
- Fill in the gaps: when ______ react, they ____ electrons, forming a positive ion.
- And the reactivity of a metal, depends on its ability to ____ electrons and form a ________ ion.
- when metals react, they ,lose electrons, forming a positive ion.
- And the reactivity of a metal, depends on its ability tolose electrons and form a positively charged ion.
Where are unreactive metals such as gold found ? 🧈
- unreactive metals such as gold, are found in the Earth as the metal itself.
What will a more reactive element do to its compound ?
- a more reactive element, will displace [push out] a less reactive element, from its compound.
How can we extract metals that are more reactive than carbon ?
- metals that are higher on the reactivity series than carbon, can be extracted using electrolysis of the molten metal compound- which will extract those metals, from their ore.
What is a ore ?
Hint: a rock
- an ore is, a rock with a large amount of metal compound.
How can metals that are less reactive than carbon be extracted ?
- metals that are less reactive than carbon can be extracted, from their oxides, by reduction with carbon.
In aqueous solutions, what do acids produce ?
- in aqueous solutions, acids produce hydrogen ions [H+].
- ; acid molecules ionise [split] in aqueous solutions, and release H+ ions.
How does the amount of free H+ ions affect the pH ?
Hint: opposite
- if there are more H+ ions= the acid will be stronger, having a lower pH.
- ; if there are less H+ ions= the acid will be weaker, and have a higher pH.
What is a base ?
Hint: producing
Hint #2; not ions
- a base is a chemical that can neutralise acids, producing a salt and water.
- Bases are typically metal oxides or metal hydroxides.
What is an alkali ?
Hint: dissolves
- an alkali, is a base that dissolves in water. [soluble in water]
In aqueous solutions, what do alkalis produce ?
- in aqueous solutions, alkalis produce hydroxide ions [OH^-]
What is the pH scale ?
Hint: tells us
- the pH scale, tells us the acidity or alkalinity of a solution.
- acids have a pH between 0 and 6, solutions with a pH of 7 and neutral and alkalis have a pH between 8 to 14.
How can we determine the pH of a solution ?
- we can determine the pH of a solution, using a pH probe- which determines the pH electronically.
- or by using universal indicator [or litmus paper]
What colour does litmus paper turn, in an acid or an alkali ?
- acid= red
- alkali= blue
What does universal indicator tell you ?
- universal indicator tells you the pH to 0.5, and:
- in a neutral solution: green is shown
- in a acid: red is shown
- and in a alkali: blue/purple is shown.
What is a neutralisation reaction ?
- neutralisation is a reaction between an acid and an alkali.
- the hydrogen ions will react with hydroxide ions to produce water.
- H+ (aq) + OH- (aq)————> H2O (l)
What is the equation for neutralisation ?
Hint: ions
- the equation for neutralisation is:
- H+ (aq) + OH- (aq)————> H2O (l)
