Answer:
The correct answer is :<u><em>a metal railing rusting in damp weather</em></u> is an example of a chemical change.
Explanation:
Physical property is defined as the property of a substance which becomes evident during physical changes. Example: Melting point
A physical change is defined as a change in which there is alteration in shape, size etc. No new substance gets formed in these reactions.
Example: Melting of ice
Chemical property is defined as the property of a substance which becomes evident during chemical changes. Example: Reactivity with other substances
A chemical change is defined as a change in which a change in chemical composition takes place. A new substance is formed in these reactions.
Example: Corrosion of iron called as rusting.
Rust is ferric oxide .
A metal railing rusting in damp weather is an example of chemical change because composition of an iron rail is changing.
Where as other examples given are the examples of physical change.
Answer:
Explanation:
Hello there!
In this case, according to the given information, it turns out necessary for us remember that the first-order kinetics is given by:
Whereas the 27.5% complete means A/Ao=0.275, and thus, we solve for the rate constant as follows:
Then, we plug in the variables to obtain:
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