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Nitrogen dioxide reacts with rain water and oxygen to form nitric acid. (i) State an equation for this reaction, including state symbols. (ii) Explain, with reference to the oxidation states of two elements, why this is a redox reaction. (iii) Describe the…
Nitric acid can form hydrogen bonds with water. Annotate the structures below to show the formation of a hydrogen bond between a molecule of nitric acid and a molecule of water. Use a dotted line to represent the hydrogen bond.
Discuss the melting points in the table below in terms of the bonding and/or intermolecular forces present in each substance.
Four allotropes of carbon, labelled W, X, Y and Z, are described in the table. Which row correctly identifies each allotrope? A. Diamond: Y, Graphite: W, Graphene: Z, Fullerene: X B. Diamond: Y, Graphite: Z, Graphene: W, Fullerene: X C. Diamond: Z, Graphite:…
A paper chromatogram is shown. The distances marked were measured along the paper. What is the retardation factor, RF, of compound Y? A. 0.40 B. 0.60 C. 0.70 D. 1.67
Hydrogen fluoride boils at 20 °C, whereas hydrogen chloride boils at −85 °C. Which type of intermolecular force accounts for the much higher boiling point of hydrogen fluoride? A. Hydrogen bonding B. Dipole-dipole forces C. London (dispersion) forces D.…
(i) State the equation for the formation of glucose by photosynthesis. (ii) Outline two advantages of using biobutanol rather than petrol (gasoline) as a fuel for vehicles.
Calculate the rise in temperature of 400.0 cm3 of water heated by the complete combustion of 2.00 g of butan-1-ol, assuming that all the energy released is transferred to the water. Use sections 2 and 14 of the data booklet.
For which of these molecules is the octet rule satisfied by every atom? I. SiCl4 II. NCl3 III. BCl3 A. I and II only B. I and III only C. II and III only D. I, II and III
Metallic bonding results from the attraction between a lattice of cations and delocalized electrons. Which of these group 1 metals has the strongest metallic bonding? A. Cs B. Rb C. K D. Na