The correct answer refers to the set of المعادن المستخدمة in coinage. These include Copper (Cu), Silver (Ag), and Gold (Au). The other options do not accurately represent coinage المعادن: Hg represents Mercury, which is not used in coins, and Cu Fe does not specify the alloy (Copper-Iron).
112
The maximum oxidation shown by manages is_________?
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Alkali metals are named as such because their oxides and hydroxides are highly water-soluble, producing basic solutions. This characteristic is a defining feature of these elements, which is why they are classified as alkali metals.
114
All the transition elements show_________________?
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115
Which one of the following alkali metals forms only normal oxide when it reacts with O2 ?
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Most metals form basic oxides, not acidic ones. For example, sodium oxide and calcium oxide are basic. Some metals, like aluminum, form amphoteric oxides. Only a few metals, typically non-metals, form acidic oxides, but some metals like chromium and manganese can form acidic oxides under certain conditions.
117
The process of separating metal from ore is called
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Oxygen and sulphur exhibit similarities in some properties, but they do not show the same oxidation states. Sulphur typically exhibits a wide range of oxidation states, whereas oxygen is mostly limited to -2 and occasionally -1 or 0.
119
Which of the following is NOT a general property of transition elements?
While some transition elements may exhibit radioactivity, it is not a defining characteristic of the entire group. Variable oxidation states, complex formation, and alloying are common properties of transition elements due to their partially filled d orbitals.
120
Which of the following statements is false about transition metals?
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