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Explain why the surface of some metals acquire a dull appearance when exposed to air for a long time support it with three examples?
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The surface of some metals acquires a dull appearance when exposed to air for a long time due to the formation of a thin layer of oxide, carbonate or sulphide on their surface by the slow action of the various gases present in air.
Arjun Bednar
Wiki User
∙ 11y agoThe surface of some metals acquires a dull appearance when exposed to air for a long time due to the formation of a thin layer of oxide, carbonate or sulphide on their surface by the slow action of the various gases present in air.
Wiki User
∙ 11y agoSome of the metal gets exposed to air; there is an oxidation process occurring on the outer layer of the metal. Owing to the oxidation; a new layer covers the existing metal; hiding its original view; giving it a dull appearance.
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Elemental calcium and magnesium metal are shiny when they are pure if the metals you worked with were not shiny explain why this was so?
They were exposed to and reacted with oxygen in the air.
Why does a banana's skin look like it is still green while the inside is ripening?
A green banana is not a ripe banana. It is still edible, but it is not fully ripe, and it will eventually turn yellow and get sweeter and softer. Having said that, if bananas are exposed to cold temperatures for several hours the ripening process will be irreversibly stopped. This might explain why you can get bananas at the supermarket that are slightly green but will not ripen an further once you get them home. In all likelihood, they were exposed to prolonged cold temperatures during shipment and/or storage.There are seven stages of ripeness. See Related questionsfor the different stages and the appearance of each stage.
Is plutonlum a metal?
Plutonium is a rare actinoid metal with a silvery/white appearance. Plutonium tarnishes when exposed to oxygen in the air and forms a dull coating when oxidised. Plutonium is a transuranic radioactive element. Chemical symbol is Pu and atomic number 94.
What does exposed persons mean?
exposed means left or being without shelter or protection: The house stoodon a windy, exposed cliff.
What will happens to a plant exposed to air?
what will happens to a plant exposed to air
What is calciums appearance?
it is a silver substance.and has grayish white when exposed to air.
The appearance of crystals in mannitol injection indicates?
It indicates that the product was exposed to cold
What would the appearance of crystals in medication indicate?
The medication has been exposed to cold
What nutrients function to prevent the appearance of bilateral symmetrical dermatitis primarily on areas exposed to the sun?
Niacin
What does the language acquisition device lad explain?
The Language Acquisition Device (LAD) is a theoretical concept introduced by Noam Chomsky to explain how children have an innate ability to acquire language. According to Chomsky, children are born with a cognitive mechanism that allows them to quickly and effortlessly learn the grammar and rules of any language they are exposed to during their critical period of language development.
Examples of directional hypothesis?
Students exposed to process-oriented writing techniques perform better than students exposed to product-oriented technique.
How can you explain the evidence that different rock layers are exposed at river level at these two sites?
mierda
How can you explain the evidence that different rock layers are exposed at river levels at these two sites?
mierda
How does the factors affect evaporation explain?
- vapours tension- temperature- pressure- area exposed to atmosphere
Examples of crenation?
Crenation occurs when animal cells are exposed to a hypertonic solution, causing shrinkage, distortion, and often leave a scalloped appearance to the edge of the cell. A common reason for crenation in red blood cells is dehydration. It is also seen when pickling and salt-curing foods.
How many hours does it take to get serious frostbite?
It depends on the temperature and how much thermal protection you have. Exposed skin in very low temperatures can acquire frostbite in minutes.
Where can you find examples of ersion due to acid rain?
places with exposed limestone or other calcium based rocks. acid rain reacts with the calcium producing fizzing and the rock dissolves. examples would perhaps be much of Yorkshire and exposed chalk such as around dover
