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Leni [432]
3 years ago
11

A blacksmith melts and shapes a block of iron into a blade. She then sets the blade, whose edges are molten, outside, where it i

s raining slightly. The blade's outer edges both solidify and then rust. Which of the following has happened to the iron throughout the day? a. The iron has undergone a physical change only. b. The iron has undergone a chemical change only. c. The iron has undergone both a physical and chemical change. d. The iron has not undergone any changes.
Chemistry
2 answers:
Margaret [11]3 years ago
4 0
The answer is C due to the rain making contact with the iron it creates moisture which cause the iron to begin oxidizing which causes the iron to rust which is a chemical reaction then the blade which was once malleable because it was heat becomes harden and rust is created as I said before the physical aspect of the iron chances due to rust developing on it it's no longer has the luster it once had
ehidna [41]3 years ago
4 0

Answer:

The correct answer is option c.

Explanation:

A physical change is defined as  a change in shape, size takes place. No new substance gets formed in these reactions.

Solid iron block → liquid iron

Liquid iron → solid blade shaped iron

Here, iron in first melted and then set into a shape of blade. Hence, physical change.

A chemical change is defined as a change in chemical composition takes place. A new substance is formed in these reactions.

Here, rusting of iron is chemical change:

Fe(s)+O_2(g)\righarrow Fe_2O_3(s)

Throughout the entire process blacksmith has changed the iron block physically by changing its size and shape. And due to action of raining in the edges of the blade rusting of an iron also took place which was a chemical change.

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What trend in ionization do you see going up and down?
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c) Finding the age of the sample :

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[A] = [A_{0}]e^{-kt}

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ln(0.35) = -(1.325 *10^{-4})(t)

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