2d) Oxygen and Oxides

How to make O2:
2H2O2 (aq) -----> 2H2O (l) + O2 (g) 

metal oxides- bases
non metal oxides- acidic
water- neutral

Carbon dioxide prepared by
CaCO3 + HCl ------> CaCl + CO2 + H2O 

Delivery of CO2
Either upwards so that it's lighter than air
Or       downwards so that it is heavier than air

• Under pressure- disowns 
• used in fire extinguishers

Thermal disposition of copper(II) carbonate:

CuCO3(s) -----> CuO(s) + CO2(g)