V=0 m/s, u=?, a = 9.8 m/s² and s = 0.8 m
u²=2×9.8×0.8=15.68
<span>u=3.959 ≈ 3.96 m/s
</span>
the compound is B.
Water is a compound because it is made up of water molecules.
Answer:
The pH of a solution of 0.00278 M of HClO₄ is 2.56
Explanation:
pH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance and is calculated as:
pH= - log [H⁺]= - log [H₃O⁺]
On the other hand
, a Strong Acid is that acid that in an aqueous solution dissociates completely. In other words, a strong acid completely dissociates into hydrogen ions and anions in solution.
HClO₄ is a strong acid, so in aqueous solution it will be totally dissociated. Then, the concentration of protons is equal to the initial concentration of acid and the pH will be calculated:
pH= - log 0.00278
pH= 2.56
<u><em>The pH of a solution of 0.00278 M of HClO₄ is 2.56</em></u>
Answer:

Explanation:
Hello,
In this case, since a change in science is widely known to be considered as a subtraction between the the final and initial values of two measured variables and is represented via Δ, here the final density is 5.43 g/mL and the initial one was 3.21 g/mL, therefore, the change in density is:

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