Reactivity

• The reactivity series is an arrangement of metals from most reactive to least reactive.
• In metal displacement reactions, more reactive metals displace less reactive ones from their compounds.
• exothermic reaction: a reaction that releases energy to the surroundings
• endothermic reaction: a reaction that absorbs energy from its surroundings
• fire is?

  exothermic
• test for oxygen: Dip glowing splint into oxygen. If oxygen is present the splint will light
• test for carbon dioxide: Add limewater (calcium hydroxide) to gas. Bubbles form if CO2 is present
• Test for hydrogen: Place a lit splint in a test tube of hydrogen gas. If hydrogen is present, the splint will burn with a squeaky pop.
• test for chlorine: damp litmus paper with water then place in chlorine. if chlorine is present it will turn white
• which of these formulae present hydrocarbons:

  a)C2H6

  b)C2H6O

  c)C2H5Br

  d)C2H4
• Displacement: the action of moving something from its place or position
• Aluminum + Iron Oxide= Aluminum Oxide + Iron
• Zinc + Hydrochloric Acid = Zinc Chloride + Hydrogen
• electrolysis: chemical decomposition produced by passing an electric current through a liquid or solution containing ions.
• Explain how electrolysis works: A metal is placed in a beaker of molten salt. The metal is then placed in a container of water. Ions are produced when the metal is placed in the molten salt.
• In electrolysis negative ions move to the positive ions and lose electrons to become an element
• what is an ion?

  An atom with an electrical charge
• What is the formula for calculating density?

  Density = Mass / Volume
• Define the term "gravity.

  Gravity is the force that attracts two objects toward each other. On Earth, it gives weight to physical objects and causes them to fall towards the ground.
• : Describe the reaction of alkali metals with water.

  Alkali metals react vigorously with water, producing hydrogen gas and an alkaline solution of the metal hydroxide.