C6.1

• what are the 3 essential elements needed by plants?

  nitrogen, phosphorous and potassium
• symptoms of nitrogen deficiency in plants?

  poor growth and yellow leaves
• symptoms of phosphorous deficiency in plants?

  poor root growth and discoloured leaves
• symptoms of potassium deficiency in plants?

  poor fruit growth and discoloured leaves
• fertilisers are substances that replace the 3 elements used by plants as they grow.

  • plant roots can only absorb these elements if they are in water soluble form
• examples of ions with nitrogen?

  NO3- (nitrate ions) and NH4- (ammonium ions)
• examples of ions with phosphorous?

  PO4(3-) - phosphate ions
• examples of ions with potassium?

  K+
• equation for the haber process:

  N2 (g) + 3 H2 (g) --> 2 NH3 (g)
• what does the haber process make?

  ammonia - NH3
• what are the conditions of the haber process?

  a pressure of 200 atmospheres

  a temperature of 450

  an iron catalyst
• what does the contact process make?

  sulfuric acid
• what are the raw materials needed for the contact process?

  sulfuric, air (for oxygen) and water