Sunday 7th September
TODAY WE ARE
LEARNING ABOUT
 What is atom economy?
TODAY'S
KEY WORDS ARE
  • P_rc_nt_g_  _t_m  _c_n_my
  • B_l_nc_d  _q__t__n
  • R_l_t_v_  F_rm_l_  M_ss
  • M_l_
    		•

    Memory Anchor:

    YOU WILL SHOW
    YOUR LEARNING BY...

    • Super Challenge:

      Stretch:

      Challenge:

    Key Questions:

    1. (Chem only) What is atom economy a measure of?
      • The amount of starting materials that end up as useful products.
    2. (Chem only) What is the formula for calculating percentage atom economy?
      • The percentage atom economy of a reaction is calculated using the balanced equation for the reaction as follows: Relative formula mass of desired product from equation / Sum of relative formula masses of all reactants from equation ? 100
    3. (Chem only) Hydrazine (N2H4) is used in some rocket fuels. Two different methods can be used to manufacture hydrazine. The reactions are: NH2Cl NH3 ? N2H4 HCl 2NH3 H2O2 ? N2H4 2H2O Calculate the atom economy for each reaction
      • 1) Mr of N2H4 = 32 2) Sum of Mr all reactants in equation 1= 68.5 3) (32 / 68.5 ) x100 46.7% 4) Sum of Mr all reactants in equation 2 = 68 5) (32/68) x 100 = 47%
    4. (Chem only) How can a chemist in a chemical plant that makes rocket fuel prevent waste products being formed?
      • (HT) A chemist can prevent waste rocket fuel being formed by Choose a reaction with few/no other products.