A force called the effort force is applied at one point on the lever in order to move an object, known as the resistance force, located at some other point on the lever
6.11% w/v of Cu2+ implies that 6.11 g of Cu2+ is present in 100 ml of the solution
therefore, 250 ml of the solution would have: 250 ml * 6.11 g/100 ml = 15.275 g
# moles of Cu2+ = 15.275 g/63.546 g mole-1 = 0.2404 moles
1 mole of CuCl2 contain 1 mole of Cu2+ ion
Hence, 0.2404 moles of Cu2+ would correspond to 0.2404 moles of CuCl2
Molar mass of CuCl2 = 134.452 g/mole
The mass of CuCl2 required = 0.2404 moles * 134.452 g/mole = 32.32 grams
4Fe + 3O2 → 2Fe2O3 <or> The chemical formula for rust is Fe2O3. Rust is formed when iron reacts with oxygen in moist air. The following chemical equation represents the reaction: 4Fe + 3O2 → 2Fe2O3. Water is necessary for the oxidation reaction to occur and to facilitate transport of the electrons.
Here is your answer
C3H8 + O2-----> CO2 + H2O
Balancing C atoms
C3H8 + O2------> 3CO2 + H2O
Balancing H atoms
C3H8 + O2------> 3CO2 + 4H2O
Balancing O atoms
C3H8 +

O2------->

CO2 +

H2O
Hence the equation is balanced.
HOPE IT IS USEFUL
i guess its e) Mn (VII)
if it was wrong pls let me knw