AS revision

What is the empirical formula of X, an organic compound with 81.7% of C and 18.3% of H by mass?

• CH3

• C2H5

• C3H8

• C4H11

What is the molecular formula of X if the molecular mass is 44

Choose isotopes with the same number of neutrons

• $_3^8Li$

• $_{22}^{48}Ti$

• $_{24}^{50}Cr$

• $_{20}^{46}Ca$

• $_{21}^{47}Ti$

Successive ionisation energies are given below:

1st    2nd     3rd      4th       5th       6th
800   1600   2400    4300   5400   10400
In what group this element is?

• 1

• 2

• 3

• 4

• 5

Choose compounds that will conduct electricity in the liquid state

• NaCl

• Br₂

• MgO

• Cu

Enthalpy change of combustion is the enthalpy change when ....... of a substance is burnt in excess oxygen under standard conditions

Choose the correct name for

• 3-chloro-5-methylhept-4-ene

• 5-chloro-3-methylhept-3-ene

• 4-chloro-2-ethylhex-2-ene

• 3-chloro-1-ethyl-1-methylhept-1-ene

You need to synthesize propanoic acid from ethene. Choose correct reagents and order to complete your synthesis.

• 1) H₂O(g),H₃PO₄; 2) acidified dichromate, heat and reflux

• 1) HCl; 2) KOH(aq); 3) acidified dichromate, heat and reflux

• 1) HCl; 2) HCN; 3) HCl(aq), heat

• 1) HCl; 2) HCN; 3) H₂, Ni