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Element E forms the oxoanion EO43−. Two possible Lewis structures of the ion are shown, with lone pairs drawn as dots. (i) Use formal charges to show which of the two structures is the better representation of the ion. (ii) The oxide E4O10…
In a titration, 25.0 cm3 of 0.100 mol dm−3 ethanoic acid, CH3COOH, was placed in a flask and 0.100 mol dm−3 sodium hydroxide solution was added from a burette. The pH curve is shown. (i) Using section 18 of the…
Glucose is made in the leaves of green plants by photosynthesis. Write the balanced equation for the overall reaction of photosynthesis.
Glucose molecules are joined together in liver cells to form glycogen, a store of energy in animals. (i) Identify the type of reaction by which glucose forms glycogen, and the small molecule released in the reaction. (iii) State the type of reaction by which…
An electron in a hydrogen atom falls from the energy level n = 4 to the energy level n = 2. Which statement is correct? A. A photon is emitted and its energy equals the difference between the two energy levels B. A photon is absorbed and its energy equals…
Suggest how the parts of the IUPAC name prop-2-enal match the structure of the compound.
Butane, C4H10, and propenal have similar molar masses, yet propenal is the less volatile. Compare and contrast the intermolecular forces in the two substances to account for this difference.
Propenal can be made by the dehydration of propane-1,2,3-triol (glycerol). CH2(OH)CH(OH)CH2OH(l) → CH2=CHCHO(g) + 2 H2O(g) (i) Calculate the standard enthalpy change of this reaction, using ΔHf⊖ of propenal(g)…
Propenal can be oxidised to compound G. G produces bubbles of gas when it is added to aqueous sodium hydrogencarbonate. The mass spectrum of G is shown. Deduce what G is and give two reasons, based on the mass spectrum.
20.0 cm3 of propane is mixed with 150.0 cm3 of oxygen and burnt completely. C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(l) Determine the total volume of gas present once the products have cooled to the starting temperature and…