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The following burette readings are recorded in one of the titrations. Final burette reading = 26.15 ± 0.05 cm3 Initial burette reading = 1.15 ± 0.05 cm3 Calculate the percentage uncertainty in the titre volume.
The student's results are plotted below. (i) Calculate the average rate at which the hydrogensulfite concentration in the 24 h flask decreased over the 12 days. Include units in your answer. (ii) Before starting, the student wrote this hypothesis: "The longer…
Suggest one way of extending the investigation so that it could lead to additional advice on storing cordial.
α-particles are the nuclei of helium-4 atoms. In an experiment based on the work of Geiger and Marsden, a beam of α-particles is directed at a very thin platinum foil and the angle of deflection, θ, of each particle is recorded by a detector that can be moved…
The presence of hydrogen in stars is deduced from lines in their spectra. (i) Outline what the emission spectrum of hydrogen looks like. Emission spectra of species that contain a single electron can be explained by a model in which the electron is held by the…
Outline why scientists have replaced earlier models of the atom with new ones.
An unknown element E has the six successive ionization energies given below. Which is the formula of the chloride of E? A. ECl B. ECl2 C. ECl3 D. ECl4
By drawing a suitable line on the graph, determine the rate at which carbon dioxide is released at the start of Experiment 1. Give your answer in cm3 s−1.
Estimate how long after the start of the experiment the piston would first move if a total mass of 750 g were loaded on it.
Suggest two reasons why less carbon dioxide is collected in the syringe when a greater mass rests on the piston.