Mercury has a very high first ionization energy due to the relativistic contraction of its 6s orbitals. This makes the valence electrons tightly bound to the nucleus, resulting in weak metallic bonding between mercury atoms. Consequently, the interatomic forces are insufficient to maintain a solid lattice structure at room temperature or 0°C, keeping it liquid.
72
Which of the following elements has a chemical symbol derived from its Latin name?
The chemical symbol for iron is Fe, which is derived from the Latin word 'ferrum'. In contrast, symbols for elements like aluminium (Al), chlorine (Cl), and carbon (C) are derived directly from their modern English names. Many transition metals have symbols originating from Latin due to their historical discovery and naming in ancient times.
73
Which of the following metals has the highest density and is considered the heaviest?
Osmium is a transition metal known for having one of the highest densities among all naturally occurring elements. Its density is approximately 22.59 g/cm³, which is significantly greater than that of iron (7.87 g/cm³), silver (10.49 g/cm³), or nickel (8.91 g/cm³), making it the heaviest metal in this group.
74
Which of the following is classified as a noble metal?
Noble metals are resistant to corrosion and oxidation in moist air. Silver is traditionally considered a noble metal due to its chemical inertness compared to base metals like iron or aluminium. While silver can tarnish, it does not easily oxidize under standard conditions. Bronze is an alloy, not a pure metal.
75
Which element is historically referred to as 'quicksilver'?
Mercury is known as quicksilver because it is a liquid metal at room temperature and has a silvery, reflective appearance. The term 'quick' historically meant 'living' or 'moving', referring to its fluid, mobile nature compared to solid metals.
76
Among the provided options, which element demonstrates the greatest tendency to lose electrons?
The tendency to lose electrons is associated with metallic character. Among the choices, Iron (Fe) is a transition metal, which generally has a much higher tendency to lose electrons to form cations compared to non-metals like Fluorine (F), Sulfur (S), or Hydrogen (H).
77
How many water molecules are associated with one formula unit of ferrous sulfate crystal?
Ferrous sulfate heptahydrate, commonly known as green vitriol, has the chemical formula FeSO4·7H2O. This indicates that there are seven molecules of water of crystallization present for every molecule of ferrous sulfate.
78
Which of the following minerals serves as an ore for copper?
Malachite is a copper carbonate hydroxide mineral with the formula Cu2CO3(OH)2. It is a significant ore of copper. In contrast, Haematite and Magnetite are primary ores of iron, and Chromite is the primary ore of chromium. Therefore, Malachite is the only copper-containing mineral listed among the options provided.
79
Which of the following elements exhibits the lowest chemical reactivity?
Among the listed elements, mercury is a noble-like transition metal with a high reduction potential, making it significantly less reactive than the active metals magnesium and aluminium, or the reactive gas hydrogen.
80
What is the correct chemical formula for Iron(III) oxide?
Iron(III) oxide contains the iron ion in the +3 oxidation state (Fe3+). Oxygen typically forms an oxide ion with a -2 charge (O2-). To achieve electrical neutrality, two Fe3+ ions (total +6 charge) must combine with three O2- ions (total -6 charge), resulting in the chemical formula Fe2O3.
