Answer:

Explanation:
Hello,
In this case, for the calculation of the pH of the given buffer we need to use the Henderson-Hasselbach equation:
![pH=pKa+log(\frac{[base]}{[acid]} )](https://tex.z-dn.net/?f=pH%3DpKa%2Blog%28%5Cfrac%7B%5Bbase%5D%7D%7B%5Bacid%5D%7D%20%29)
Whereas the pKa for benzoic acid is 4.19, the concentration of the base is 0.15 M (sodium benzoate) and the concentration of the acid is 0.25 M (benzoic acid), therefore, the pH turns out:

Regards.
Answer:
A reaction that combines simpler reactants to form a new compound is called a
<h2>Synthesis reaction.</h2>
Hey there!
The correct answer to your question is: Spectrum
A spectrum, by definition, is a range of colors which are produced by separating certain colors of light.
Thank you!
Late answer:
Chromosphere.
Instability
Explanation:
Isotopes decays because they are unstable. Stable isotopes do not decay.
- For every atomic nucleus, there is a specific neutron/proton ratio.
- This ratio ensure that a nuclide is stable.
- For example, fluorine F, is 10/9 stable.
- Any nucleus with a neutron/proton combination different from its stability ratio either too many neutrons or too many protons will become unstable.
- Such nuclide will split into one or more other nuclei with the emission of small particles of matter and considerable amount of energy.
Learn more:
Radioactive brainly.com/question/10125168
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