Metal Guessing Challenge

Was first discovered in 1774 and it is the 5th most abundant metal in the earth’s crust. Used by pre-historic cave painters around 30 000 years ago?

• Carbon

• Manganese

• Molydenum

• Cadmium

Primary manganese ore mineral include:

• Braunite    

• Vredenburgite

• Jacobsite

• Polandite

Manganese minerals are widely distributed as:

• Stomatolite

• Rhodochrosite

• Khandalite

• Pyrulosite

Which of the following statements is/are not true about manganese?

• Essential human dietary element?

• Important for muscle development

• Important for bone formation

• Important in macronutrient metabolism

Manganese is too brittle to be of much use as a pure metal? Thus, it is most commonly used in alloys, such as steel. The extremely strong manganese steel alloy used for railway lines contains:

• 13% Mn

• 1% Mn

• 20% Mn

• 5% Mn

Which of the following countries are the main manganese producing countries in the world?

• Gabon

• Russia

• China

• South Africa

• Australia

The melting point of manganese is:

• 1350 ͦC

• 1425 ͦC

• 1246 ͦC

• 1440 ͦC

Which of the following facts are not true about pure manganese?

• Highly reactive

• Burns in oxygen

• Dissolves in water

• Dissolves in dilute acids

Common oxidation states of manganese are:

• 7, 6, 5, 2, 0, -1

• 7, 6, 4, 3, 0, -1

• 6, 5, 4, 3, 2, 0

• 7, 5, 3, 2, 0, -2

KMnO₄ is the most commonly used manganese salt because of its oxidizing properties; it is used as a topical medicine. What is the oxidation state of manganese in this salt, which is especially responsible for its purple color?

• +4

• +2

• +6

• +7