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3 years ago

Which of the following is not true of chemical changes? (2 points)

Chemistry

1 answer:

Fynjy0 [20]3 years ago

4 0

A chemical change means that a new substance was formed. Different from what it was before the change took place.

Flammability and decomposition are examples of chemical changes. <<<This is chemical change. An example can be seen in fruit. When a cut apple stays to long in the open it turns brown. This is because it is oxidized. Even if the apple tastes the same on the molecular level it has changed

Chemical changes involve a rearrangement of atoms to form new substances. <<< It states even in the definition of chemical change that a new substance has to be formed

Chemical changes can often be identified by the formation of a gas or a solid or the release of heat. <<< In a chemical change something extra may be created. This is different from an ice cub melting (which would be physical change). Although it goes from solid to liquid it is still water, and there is no extra product

Nothing is altered at the molecular level during a chemical change. <<<This is false

Hope this helped!

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So, number of moles of NaOH = Volume × Molarity

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= Molarity × Volume

= 1.00 M × 1.00 L

= 1.00 mol

Hence, addition of sodium acetate in NaOH will lead to the formation of acetic acid as follows.

$CH_{3}COONa + NaOH \rightarrow CH_{3}COOH$

Initial : 1.00 mol 1.00 mol

NaoH addition: 0.05396 mol

Equilibrium : (1 - 0.05396 mol) 0 (1.00 + 0.05396 mol)

= 0.94604 mol = 1.05396 mol

As, pH = pK_{a} + log $\frac{[CH_{3}COONa]}{[CH_{3}COOH]}$

= 4.74 + log $\frac{0.94604}{1.05396}$

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Therefore, change in pH will be calculated as follows.

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<u>Answer:</u> The rate law expression for the given reaction is written below.

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