(Originais Teachy 2023) - Question Hard of Sciences

In the solutions used in laboratories, the concentrations of ions $$\mathrm{H}_{3} \mathrm{O}^{+}$$ are usually small and a simple way to express the hydrogenionic concentration of a solution is through pH. Solutions of weak acids and bases present, in solution, an equilibrium between the various particles and, in this case, we have the equilibrium constant, that is, the ionization constant. A solution of $$1.10^{-3} \mathrm{mol}^{-1}$$ of bromoacetic acid $$\left(\mathrm{BrCH}_{2} \mathrm{CO}_{2} \mathrm{H}\right)$$ has an ionization constant equal to $$6.3.10^{-5} \mathrm{e}$$ and a solution of $$1.10^{-3} \mathrm{mol}^{-1}$$ of 4-chlorobenzoic acid $$\left(\mathrm{ClC}_{6} \mathrm{H}_{4} \mathrm{CO}_{2} \mathrm{H}\right)$$ has an ionization constant of $$1.0.10^{-4}$$. Given the following statements, I. 4-chlorobenzoic acid has a higher $$\mathrm{pH}$$ than bromoacetic acid. II. Bromoacetic acid is weaker than 4-chlorobenzoic acid. III. Since the concentrations are equal, both acids have the same $$\mathrm{pH}$$. IV. Bromoacetic acid has a higher $$\mathrm{pH}$$ than 4-chlorobenzoic acid. v. 4-chlorobenzoic acid is weaker than bromoacetic acid. It is verified that only ii and iv are correct.

What are the problems caused by the standardization of crops?

Technological development has allowed the exploitation of natural resources in an increasingly intense way. However, this unrestrained exploitation has generated serious environmental problems. Deforestation is an example of these problems. Deforestation is the destruction of forest cover for agricultural use, urbanization, or timber extraction. Which of the following environmental impacts can be caused by deforestation?

Explain what is the relationship between frequency and wavelength and how this affects the propagation of sound and light waves. Then, provide examples of everyday situations where this can be observed and discuss the importance of these waves in our communication and daily life.