If 25cm of sodium hydroxide solution containing 4.0g per litre of solution neutralized 50cm of a monobasic acid,HX containing 1.8g of acid, calculate the relative formula mass of the acid
Given that 25cm of NaOH solution containing 4.0g/L of solution neutralized 50cm of the monobasic acid HX containing 1.8g of acid:
Let's first calculate the number of moles of NaOH in 25cm of solution:
Concentration of NaOH = 4.0g/L
Volume of NaOH solution = 25cm = 0.025L
Number of moles of NaOH = (4.0g/L) * (0.025L) / (40.0 g/mol) = 0.0025 moles
Since NaOH is a strong monobase, we know that the number of moles of acid (HX) will be equal to the number of moles of NaOH. Therefore, the number of moles of HX is also 0.0025 moles.
Now, we can calculate the relative formula mass of the acid HX:
Mass of acid HX = 1.8g
Number of moles of HX = 0.0025 moles
Molar mass of acid HX = Mass of acid / Number of moles = 1.8g / 0.0025 moles = 720 g/mol
Therefore, the relative formula mass of the acid HX is 720 g/mol.