0.5g of fuming h2s04 oleum is diluted with water. This solution is completely neutralized by 26.7ml of 0.4N naoh. Find the percentage of free s03 in the smaple solution. The answer 20.6%
Assume that 50ml of 0.01M edta solution were added to 25ml of solution and the excess edta required 20ml of 0.005M mg solution. Calculate ppm co2 present.
the answer 942ppm
Find the concentration of calcium in ppm in a 3.5g pill that contains 40.5mg of ca
The answer 1.16ppm
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1. Percentage of free SO3 in the sample solution:
To find the percentage of free SO3, we need to determine the amount of SO3 in the sample solution. From the given information, 0.5g of fuming H2SO4 oleum is present. We also know that it takes 26.7ml of 0.4N NaOH to neutralize it.
First, we need to calculate the number of moles of NaOH used in the neutralization:
Number of moles of NaOH = concentration (N) × volume (L)
= 0.4N × 0.0267L
= 0.01068 moles
Since the reaction between NaOH and H2SO4 is 1:1, the number of moles of H2SO4 in the sample solution is also 0.01068 moles.
The molar mass of H2SO4 is 98 g/mol, so the mass of H2SO4 in the sample solution can be calculated as follows:
Mass of H2SO4 = moles × molar mass
= 0.01068 moles × 98 g/mol
= 1.04664 g
To find the percentage of free SO3, we need to subtract the weight of H2SO4 from the weight of oleum (0.5g):
Weight of free SO3 = Weight of oleum - Weight of H2SO4
= 0.5g - 1.04664g
= -0.54664g (Negative value means excess H2SO4)
Finally, we can calculate the percentage of free SO3:
Percentage of free SO3 = (Weight of free SO3 / Weight of oleum) × 100
= (-0.54664g / 0.5g) × 100
≈ -109.33%
It seems there's an error in the given answer. The calculated percentage is negative, which indicates there is an excess of H2SO4. Please double-check the information or calculations provided.
2. ppm CO2 present:
To calculate the ppm (parts per million) of CO2 present, we need to know the volume and concentration of the CO2 solution. However, the information provided in the question only mentions adding 50ml of 0.01M EDTA solution to 25ml of the solution and using 20ml of 0.005M Mg solution to determine excess EDTA.
Without knowing the concentration or volume of the CO2 solution, it's not possible to calculate the ppm of CO2 present. Please provide additional information or clarify the given question.
3. Concentration of calcium in ppm in a 3.5g pill:
To find the concentration of calcium in ppm, we need to convert the weight of calcium (in mg) present in the 3.5g pill.
Given that the pill contains 40.5mg of calcium, we can calculate the concentration as follows:
Concentration of calcium = (Weight of calcium / Weight of pill) × 1,000,000
= (40.5mg / 3.5g) × 1,000,000
≈ 11,571.43 ppm
The concentration of calcium in the pill is approximately 11,571.43 ppm.
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