eq energy change

• The magnesium needed heating before it would react. What conclusion can you draw from this?

  The reaction has a high activation energy
• Give one advantage of using nanoparticles in sun creams.

  Better coverage
• Give one disadvantage of using nanoparticles in sun creams

  Potential cell damage to the body
• Why are catalysts used in chemical reactions?

  speed up the reaction
• Explain how a covalent bond holds two atoms together.

  electrostatic force of attraction between shared pair of negatively charged electrons 1 and both positively charged nuclei
• Explain how a catalyst increases the rate of the reaction

  a catalyst provides an alternative reaction route that has lower activation energy