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Naturally occurring gallium consists of two isotopes: 60 % of the atoms contain 38 neutrons and the remaining 40 % contain 40 neutrons. (i) Use section 7 of the data booklet to deduce the nuclear symbol of the heavier isotope. (ii) Calculate the relative…
Gallium forms a sulfate of formula Ga2(SO4)3. (i) Both ionic and covalent bonding are present in this compound. State which particles are held together by each type of bond. (ii) Contrast covalent and ionic bonds in terms of what happens to the valence…
Gallium was discovered in 1875 from its atomic emission spectrum, which contains two strong violet lines. (i) State which feature of an emission spectrum allows the ionization energy of the element to be determined. (ii) Using sections 1, 2 and 9 of the data…
Which of the following could be the empirical formula of a compound with Mr = 70? I. CH2 II. C4H6O III. C5H10 A. I and II only B. I and III only C. II and III only D. I, II and III
Describe how a standard aqueous solution of potassium manganate(VII) can be prepared from the solid.
Describe the steps by which this standard solution is turned into a calibration curve for the colorimeter.
Explain how the calibration curve is then used to determine the concentration of KMnO4 in a reaction mixture of unknown concentration.
The kinetic molecular theory describes matter as particles in constant motion. State and explain two physical properties of a gas using this model.
A strong acid is placed in a conical flask and a strong base is added to it from a burette. Which graph shows the pH curve for this titration? A. Graph A B. Graph B C. Graph C D. Graph D
Draw a line of best fit on the graph, extrapolating it beyond the range of the data.