Bonding

• If a metal atom, loses electrons, it forms a what…?

  Positive ion
• if a non-metal atom, gains electrons, it forms a what…?

  Negative ion
• what is ionic bonding between?

  Metal and nonmetal
• what does covalent bonding consist of?

  Sharing electrons between nonmetals
• breakdown the formula for sulphuric acid (H2SO4)

  Two hydrogen atoms

  When sulfur atom

  For oxygen atoms
• what is a mixture?

  A combination of two or more substances that are not chemically bonded.
• what are the methods of separating a mixture?

  Filtration, simple, distillation, fractional distillation, chromatography, crystallisation.
• what would be the first step in a paper chromatography experiment?

  Draw a line at the bottom of the sheet of filter paper (using pencil)
• what would be the second step of a paper chromatography experiment?

  Add spots of your ink on the line and placed a sheet in a beaker of solvent for example, water.
• what would happen in step three of the chromatography experiment?

  The solvent will seep up the paper carrying the ink with it
• what would step for 4 of the paper chromatography experiment?

  What’s the solvent has reach the top of the paper take it out to dry.
• what would be the last step in paper chromatography experiment?

  The end result of a pattern of spots called a chromatogram
• describe filtration.

  Use a piece of filterpaper forwarded, intercom shape and put into a funnel.

  Place the phone on with the filter paper over a beaker.

  Pour your mixture through the funnel.

  The solid will be left in the filter paper and the liquid will go into the beaker.
• describe evaporation.

  Pour your solution into an evaporating dish

  Slowly, heat the solution

  The solvent will evaporate And the solution will become more concentrated

  Eventually, crystals will start to form

  Keep heating the dish until all you have left is dry crystals
• what does evaporation and crystallisation separate?

  Separate, a soluble salt from a solution
• What are the differences between crystallisation and evaporation?

  Evaporation is fast

  However, you can only use if the salt doesn’t decompose when heated

  Otherwise, crystallisation is best
• describe the process of crystallisation.

  Put a solution into an evaporating dish in gently heat

  Some of the solvent will evaporate, and the solution will become more concentrated

  When you see chris to start to form, remove the dish and leave it to cool

  The salt will begin to form crystals as it becomes insoluble in the cold, highly concentrated solution

  Go to the crystals out of the solution and leave them in one place to dry.
• What would be step one in a simple, distillation practical

  Slowly heating the solution, until the part with the lowest boiling point evaporates
• what would be a step two in a simple, distillation practical?

  Developer is then cooled condenses and collected
• what would be a problem with simple distillation?

  You can only use it to separate things with very different boiling points

  If the temperature goes higher than the boiling point of the substance, with the higher boiling point, they will mix again
• when might you use fractional distillation over Simple distillation

  A mixture of liquids with similar boiling points
• what would be the first step in a fractional, distillation practical

  Put your mixture in a flask and add the fractioning column on top
• Second step in fraction, distillation, practical

  Gradually heat it

  The different liquids have different boiling points, so they will evaporate at different temperatures
• third step in fraction, distillation practical

  The column is cooler towards the top, so they will condense