Answer:
Physical change
Explanation:
Chemical change is defined as the process in which new substance with different properties is formed from old substance and the process is irreversible while physical change is a reversible process and changes only physical properties of a substance.
<em>The given experiment is an example of physical change because it is just the physical act of dissolving. The metal disk is dissolving in sodium acetate and the process is exothermic and the process is reversible as well.</em>
Hence, the correct answer is "physical change".
The claim: "If the nucleus were the size of a grape, the electrons would be one mile away on average" is reasonably accurate because the ratios between the nucleus's sizes and the distances (between electrons and nucleus) for the two given examples are in the same order of magnitude.
To know if the claim is accurate we need to calculate the ratio of the size of the nucleus (the same as a grape) and the distance between the electrons and the nucleus for example 1 (r₁):
(1)
and to compare it with the ratio of the size and the distance given in example 2 (r₂):
(2)
<em>Where:</em>
s₁: is the size of the nucleus (like the size of a grape)
d₁: is the distance between electrons and nucleus of example 1 = 1 mile
s₂: is the average diameter of the nucleus = 10⁻¹³ cm
d₂: is the average distance between electrons and nucleus of example 2 = 10⁻⁸ cm
Assuming that the diameter of a grape is 3 cm (in a spherical way), the ratio of the <u>first example</u> is (eq 1):

Now, the ratio of the <u>second example</u> is (eq 2):
Since r₁ and r₂ are in the same order of magnitude (10⁻⁵), we can conclude that the given claim is reasonably accurate.
You can learn more about the nucleus of an atom here: brainly.com/question/10658589?referrer=searchResults
I hope it helps you!