The pebbles become smooth and even because of erosion. the waves from the sea rub against the pebbles this is erosion. x
Answer:
B. pOH = 14 - pH and D. pH = 14 - pOH.
Explanation:
Hello,
In this case, we must remember that pH and pOH are referred to a measure of acidity and basicity respectively, since pH accounts for the concentration of H⁺ and pOH for the concentration of OH⁻ in a solution. In such a way, since the maximum scale is 14, we say that the addition between the pH and pOH must be 14:

Therefore, the correct answers are B. pOH = 14 - pH and D. pH = 14 - pOH since the both of them are derived from the previous definition.
Best regards.
Answer:
4.15×10⁻²¹ moles of Sn
Explanation:
This question can be solved by a simple rule of three.
We know that 1 mol contains 6.02×10²³ particles.
In this case, our particles are the atoms, so:
6.02×10²³ atoms / 1 mol . 2500 atoms = 4.15×10⁻²¹ moles.
The knowledge of mol can be applied for everything:
A mol of molecules
A mol of atoms
A mol of a compound