<h3><u>Answer;</u></h3>
= 78 g of NaOH
<h3><u>Explanation;</u></h3>
Concentration = Moles of solute/Volume of solution
Thus;
Moles of the solute = Volume × Concentration
= 7.80 Moles/L × 0.250 L
= 1.95 moles
But; 1 mole of NaOH = 40.0 g
Thus;
Mass of NaOH = moles × molar mass
= 1.95 moles × 40 g/mole
<u> = 78 g of NaOH</u>
1mile/13min * 1min/60sec * 63360in/1mil = 63360in/780sec = 81.23 in/sec
The oxidation state of iron may be 2,3 or 6 and the most common is 3 & this is our case, Fe^3+ can react with Oxygen (O2), which have fixed oxidation state (2), to form Fe2O3.
Two ions of iron and 3 ions of Oxygen with 2:3 ratio.