chemical changes

• When metals react with oxygen, it is called oxidation because the metals gain oxygen, and form metal oxides.
• A chemical reaction in which a substance loses oxygen is called reduction.
• When metals react with other substances the metal atoms form positive ions.
• fill in the gaps.

  A) LITHIUM

  B) MAGNESIUM

  C) ALUMINIUM

  D) CARBON

  E) IRON

  F) HYDROGEN

  G) GOLD

  
• A more reactive metal can displace a less reactive metal from a compound.
• Metals lose electrons more easily than less reactive metals. When a more reactive metal reacts with a compound containing a less reactive metal, the more reactive metal atoms form positive ions more easily. 
• Metals less reactive than carbon can be extracted from their oxides by reduction with carbon, which involves the loss of oxygen.
• label the diagram

  A) electrolysis

  B) heating

  C) various

  
• Oxidation is the loss of electrons and reduction is the gain of electrons.
• label the diagram with charges.

  A) +

  B) 2+

  C) 3+

  D) 3-

  E) 2-

  F) -

  
• label the diagram

  A) oxidation

  B) reduction

  C) more

  D) electrons

  
• A redox reaction is one in which both oxidation and reduction take place.
• Acid + metal → salt + hydrogen
• Acids are neutralised by alkalis and bases.
• when reacting with an alkali/base, these produce:

  hydrochloric acid - HCl - chlorides

  nitric acid- HNO3 - nitrates

  sulfuric acid- H2SO4 - sulfates
• Strong acids are completely ionised in aqueous solutions.
• Steps for writing ionic equations:

  1. Write the balanced symbol equation.
  2. Identify the soluble compounds using the solubility rules or the aqueous state symbol.
  3. Split up the soluble compounds into ions.
  4. Cancel ions that appear on both sides of the equation.
  5. Write out the resulting ionic equation.
• label the diagram:

  A) soluble

  B) insoluble

  C) OH-

  
• complete the ionic formula:

  H+(aq) + OH-(aq) --> H20(l)
• Salt solutions can be crystallised to produce solid salts.
• soluble salts can be made from acids by reacting them with solid insoluble substances
• RP1 involves the preparation of a pure, dry sample of a soluble salt from an insoluble oxide or carbonate using a Bunsen burner to heat dilute acid, and a water bath or electric heater to evaporate the solvent.
• label the diagram

  A) solid

  B) fliter paper

  C) filter funnel

  D) solution

  E) solid and solution

  
• label the diagram

  A) evaporating basin

  B) gauze

  C) tripod

  D) bunsen burner

  E) boiling water

  F) solution

  
• label the diagram pookie

  A) acidic

  B) neutral

  C) alkaline

  D) hydrochloric

  E) water

  F) sodium

  
• Universal indicator is a mixture of a variety of other indicators and can be used to measure the approximate pH of a solution. A more accurate value can be obtained using a pH probe.
• RP2 involves using appropriate apparatus to make and record a range of measurements accurately, including volume of liquids. It also involves determining the concentration of one of the solutions in mol/dm3 and g/dm3.
• label the diagram

  A) burette

  B) acid

  C) clamp stand

  D) alkali

  E) indicator

  
• fill in the gaps bbygirl

  A) 25

  B) conical

  C) alkali

  D) indicator

  E) conical

  F) burette

  G) volume

  H) burette

  I) alkali

  J) conical

  K) end-point

  L) volume

  M) concordant

  
• fill in the gaps fatty

  A) sulfuric

  B) cylinder

  C) beaker

  D) acid

  E) insoluble base

  F) filter paper

  G) funnel

  H) excess

  I) evaporating basin

  J) water bath

  K) cool

  L) filter paper

  
• Examples of strong acids are hydrochloric, nitric and sulfuric acids.
• A weak acid is only partially ionised in aqueous solution
• Examples of weak acids are ethanoic, citric and carbonic acids.
• As the pH decreases by one unit, the hydrogen ion concentration of the solution increases by a factor of 10.