100ml of h2s04 solution having molarity 1M and density 1.5g/ml is mixed with 400ml of water. Calculate final molarity of h2s04 solution if final density 1.25g/ml.
Ans is 0.227M
Who help me thanks a lot
I never worked a problem like this before.
mass 100 mL of 1M H2SO4 = 1.5 g/mL x 100 mL = 150 grams.
mass H2SO4 in that 100 mL is 98 g/mol x 100/1000 = 9.8 g H2SO4
g H2O in that 100 solution is 150g - 9.8 g H2SO4 = 140.2
g H2O in the final solution is 400 + 140.2 = 540.2 and final mass of that solution is 540.2 + 9.8 g H2SO4 = 550 grams.
Then 1.25 g/mL x #mL = 550 g
# mL solution is 440 mL.
Then mL1 x M1 = mL2 x M2
100 x 1 = 440 x M2
Solve for M2 = 0.227
no of moles = molarity x vol
no of moles of H2SO4 = 1 x 100/1000 = 0.1
final vol = total weight /density
( wt of H2SO4 + wt of H20)/ 1.25
(1.5 x 100 + 400 x1 ) 1.25
= 550/1.25 = 440 ml
molarity of final solution = moles/vol in litre
0.1 /440/1000 = 0.227
To calculate the final molarity of the H2SO4 solution, you need to use the concept of dilution and the relationship between moles, volume, and concentration.
Here are the steps to solve the problem:
Step 1: Calculate the initial moles of H2SO4:
To find the initial moles, we multiply the initial volume (100 mL) by the initial molarity (1 M):
Initial moles = Initial volume (L) x Initial molarity
Initial moles = 100 mL ÷ 1000 mL/L x 1 M
Initial moles = 0.1 L x 1 mol/L = 0.1 mol
Step 2: Calculate the initial mass of H2SO4:
To find the initial mass, we multiply the initial volume (100 mL) by the density (1.5 g/mL):
Initial mass = Initial volume x Density
Initial mass = 100 mL x 1.5 g/mL
Initial mass = 150 g
Step 3: Calculate the final volume of the solution:
The final volume is calculated by adding the initial volume of the H2SO4 solution (100 mL) to the volume of water added (400 mL):
Final volume = Initial volume + Volume of water
Final volume = 100 mL + 400 mL
Final volume = 500 mL
Step 4: Calculate the final mass of the solution:
The final mass is calculated by adding the mass of the H2SO4 solution to the mass of water:
Final mass = Initial mass + Mass of water
Final mass = 150 g + 400 mL x 1.0 g/mL (since the density of water is approximately 1 g/mL)
Final mass = 150 g + 400 g
Final mass = 550 g
Step 5: Calculate the final molarity of the H2SO4 solution:
To find the final molarity, we need to calculate the final moles of H2SO4 and divide it by the final volume of the solution:
Final moles = Initial moles of H2SO4
Final molarity = Final moles (mol) / Final volume (L)
Final molarity = 0.1 mol / 0.5 L
Final molarity = 0.2 M
Note: The final molarity obtained by this calculation is not the correct answer provided in the question. There may be an error in the given answer.
So, according to the calculations, the final molarity of the H2SO4 solution is approximately 0.2 M, not 0.227 M as mentioned in the answer.