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A 4.85 g sample of anhydrous sodium sulfate is dissolved in water and the solution made up to 250 cm3 in a volumetric flask.
What is the concentration in mol dm−3 of sodium sulfate in the solution?
Concentration= amount of solute/volume im dm3Solution in dm3 = 250/1000 =0.25dm3now concentration in g/dm3=4.85/0.25 =19.4g/dm3Molecular mass of sodium sulfate is 142.04Now concentration in mol/dm3 becomes,19.4/142.04=0.13mol/dm3
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Why should you never heat a volumetric flask, or add a hot solution to a volumetric flask?
Because it can be broken. Unlike round bottom flask, volumetric flask has local heating due to the tension in the glass.
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What is the concentration of a solution of sodium hydroxide, 25.0 cm3 of which requires 20.0 cm3 of hydrochloric acid of concentration 0.100mol/dm3 for neutralization?
NaOH + HCl = NaCl + H2O M(HCl ) = 20x10-3[dm3] * 0.1 [mol/dm3] = 20x10-4 mol M(NaOH) = M(HCl) = 20x10-4 mol N (NaOH) = 20x10-4 mol / 25x10-3...
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1 g of NaOH was added to 30 cm3 of 1 mol/dm3 HCl. How many cubic meters 0.1 mol/dm3 KOH solution will neutralize excess acid?
The chemical equation is HCl + NaOH = NaCl + H2O n(NaOH) = m(NaOH)/MW(NaOH) = 1/(23 +16 +1) = 0.025 mol 30 cm3 = 30 mL = 0.030 L 1mol/dm3...
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If the concentration of a solution of NaOH is 4g/dm3 ,then what mass of NaOH is contained in 250 cm3 of this solution ? [1 dm3 = 1000 cm3 ]?
Express concentration in g/cm3: c = 4g/dm3 = 4g/1000 cm3 = 0.004 g/cm3 Find the mass of NaOH: m = c*V = 250 cm3 * 0.004 g/cm3 = 1g
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Calculate the concentration of OH- ions when reacting with 100 cm3 of KOH solution, concentration 0.09 mol / dm3 with 120 cm3 of H2SO4 solution with concentration 0.1 mol / dm3!
The reaction given:2KOH + H2SO4 = K2SO4 + 2H2OAs 1 L = 1dm3 and 1 ml = 1 cm3, the number of moles of the reactants equals:n(KOH) = M × V = 0.09...
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What will be the quantitative concentration of the newly formed solution if we add 800 cm3 of water to 400 cm3 of hydrochloric acid solution, mass concentration of 12.25 g / dm3?
Solution:hydrochloric acid - HClConvert units:(800 cm3) × (0.001 dm3 / 1 cm3) = 0.8 dm3 H2O(400 cm3) × (0.001 dm3 / 1 cm3) = 0.4 dm3 HCl(0.4 dm3 HCl) ×...
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What will be the mass concentration of the HCl solution if 400 cm3 of water is added to 100 cm3 of a solution with a mass concentration of 10 g / dm3?
(100 cm3) × (1dm3 / 1000 cm3) = 0.1 dm3Solution:(0.1 dm3 HCl) × (10 g HCl / 1 dm3 HCl) = 1 g HClMass of solute = 1 g HClVolume...
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How many liters of nitric acid solution, with a concentration of 0.05 mol / dm3, can be made if we have 150 cm3 of 60% nitric acid, whose density is 1.37 g / cm3?
Solution:Calculate the mass of nitric acid solution:Mass of HNO3 solution = Solution volume × Density of solutionMass of HNO3 solution = 150 cm3 × 1.37 g/cm3 = 205.5 g Calculate...
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<ol><li>Calculate the volume of the original sample needed if you would use a 50 mL volumetric flask, a 100 mL volumetric flask, and a 250 mL volumetric flask to prepare a dilution of 1:25.</li></ol>
Ratio 1:25 means that there have to be 1+25 = 26 equal parts.1) The volume of the original sample needed if we would use a 50 mL volumetric flask is...
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