This solution was placed in a burette and 18.4 cm3 was required to neutralise 25 cm3 of 0.1 moldm-3 NaOH. Deduce the molecular formula of the acid and hence the value of n. 5. Sodium carbonate exists in hydrated form, Na2CO3.xH2O, in the solid state. 3.5 g of a sodium carbonate sample was dissolved in water and the volume made up to 250 cm3. 25.0 cm3 of this solution was titrated against 0.1 moldm-3 HCl and 24.5 cm3 of the acid were required.
Observing Changes – Materials & Procedures Materials Water Copper (II) sulphate (Powder) Copper (II) sulphate solution Iron nail Sodium carbonate Hydrochloric acid Magnesium ribbon Flame (candle) Sugar Aluminum foil Test tubes Test tube rack Tongs Medicine dropper Spoons Beakers Safety goggles Scoopulas Procedures Water and Copper (II) Sulphate Procedure 1. Add a small amount of solid copper (II) sulphate to a test tube with a scoopula. Record the physical properties. 2. Write a hypothesis on what you think will happen when water is added.
Use a calorimeter to measure the temperature change in each of three reactions. Calculate the heat of reaction, ∆H, for the three reactions. Use the results to confirm Hess’s law. Ev al Figure 1 ua tio Na+(aq) + OH–(aq) + H+(aq) ) + Cl–(aq) → H2O(l) + Na+(aq) + Cl–(aq) ∆H3 = ? n (3) Solutions of aqueous sodium hydroxide and hydrochloric acid react to form water and aqueous sodium chloride.
Part C: Density of Sodium Chloride (NaCl) Solution, a sample of NaCl was obtained and measured using a 100mL beaker and a 10mL pipet to determine the concentration of the solution. In order to obtain the appropriate result, a calibration graph and density measurement was used to determine the concentration of the sodium chloride solution. In conclusion, based on the water temperature of 21.8°C in part A’s graduated cylinder experiment obtained, it was determined that the average density was .0973g/mL with a percentage error of 2.5%. When graphed the measurement was equal to Y=0.988x. Part B: The graduated pipet’s average density at 22.3 °C was determined to be 0.9785g/mL with a percentage error of 1.89% shows the graduated pipet to be more accurate and precise.
Objectives: The purpose of this lab is to observe the reaction of crystal violet and sodium hydroxide by looking at the relationship between concentration and time elapsed of the crystal violet. CV+ + OH- CVOH To quantitatively observe this reaction of crystal violet, the rate law is used. The rate law tells us that the rate is equal to a rate constant (k) multiplied by the concentration of crystal violet to the power of its reaction order ([CV+]p) and the concentration of hydroxide to the power of its reaction order ([OH-]q). Rate = k[CV+]p[OH-]q To fully understand the rate law, concentrations of the substances must be looked at first. The concentration is measured in molarity.
Hydrate Lab The purpose of this lab is to analyze the percent water in a crystalline hydrate and to indentify the hydrate from a list of possible unknowns. The solid hydrate will be heated to remove the water, and the percent can be found by measuring the mass of the solid before and after heating. The hydrate will be indentified by comparing the percent water in the hydrate with the percent water calculated for the possible unknown. Before the lab there are pre-lab questions: 1. Describe the three general safety rules for working with a Bunsen burner.
Conclusion 10 Grams of Potassium chlorate when decomposed produces 3.915576 grams oxygen gas and 6.083363 grams potassium chloride Atomic Weight of Magnesium Introduction In this lab we will determine the atomic weight of magnesium by measuring the amount of hydrogen gas evolved when hydrochloric acid reacts with magnesium. The reaction is as follows: Mg + 2HCl -> H2 + Mg2+ (aq) + 2Cl- (aq) There is a one to one relationship between the number of moles of hydrogen gas evolved and the
This reaction can be summed up using the following formula: 5Fe2++8H++MnO4- →5Fe3++Mn2++4H2O After standardization, the potassium permanganate solution is then titrated with 3 different magnesium oxalate solutions. To find the concentration of the C2O42- the balanced net ionic redox reaction formula is used: 5C2O42-+16H++2MnO4- →10CO2+2Mn2++8H2O It is important to note the addition of sulfuric acid (9M H2SO4) in performing this experiment because of the following reasons: 1) Sulfuric acid keeps the iron (II) from air oxidizing into iron (III) 2) Sulfuric acid keeps the iron (II) from hydrolyzing into Fe(OH)2 3) Sulfuric
These can be removed by adding a solution of potassium iodide, KI. In this investigation, you will combine different pairs of solutions to discover which cation/anion combinations result in the formation of a precipitate. Purpose: To identify which anion could be used to precipitate
Determination of the percentage purity of aspirin Introduction The aim of this experiment is to determine the percentage purity of 2-ethanoyl-hydrobenzoic acid (acetylsalicylic acid) in aspirin tablets. A known amount of standard sodium hydroxide solution is used in excess to hydrolyze a known mass of aspirin tablets: CH3COOC6H4COOH(s) + NaOH(aq) → C9H7O4Na(s) + H2O(l) The unused sodium hydroxide which remains is then titrated with standard nitric acid solution of 1 mol. NaOH(aq) + HCl(aq) → NaNO3(s) + H2O(l) The amount of alkali required for the hydrolysis can now be calculated and from the above equation, the amount of moles of acetylsalicylic acid which has been hydrolyzed can be found. Research question | Independent variablesnumber