Buffers - mixtures of conjugate acid and conjugate base at ±1 pH unit from pH = pKa. Resistant to changes in pH in response to small additions of H+ or OH-. ... Polyprotic acids - dissociation of each H+ can be treated separately if the pKa values are different
Answer:
0.004522 moles of hydrogen peroxide molecules are present.
Explanation:
Mass by mass percentage of hydrogen peroxide solution = w/w% = 3%
Mass of the solution , m= 5.125 g
Mass of the hydrogen peroxide = x
Mass of hydregn pervade in the solution = 0.15375 g
Moles of hydregn pervade in the solution :
0.004522 moles of hydrogen peroxide molecules are present.
Answer:
Metals lose electrons to become cations.
Explanation:
For example, sodium loses an electron to become a sodium cation.
Na· ⟶ Na⁺ + e⁻
A is <em>wrong</em>. Nonmetals gain electrons to become anions.
B is <em>wrong</em>. Metals lose electrons.
D is <em>wrong</em>. Nonmetals gain electrons to become anions.
<span>The composition of a fertilizer is usually express in NPK number. NPK number is in terms of Percent by mass of the said element which are Nitrogen, Phosphorus and Potassium. A 15-35-15 fertilizer has 15%
Nitrogen, 35% Phosphorous, and 15% Potassium by mass. If you have 10 g of this
fertilizer, to get the number of moles of phosphorus, you multiply the mass by
35%, which is equal to 10*0.35 or 3.5 g phosphorus. Then you divide the
calculated mass of phosphorous by its molar mass which is 30.97 g/mol.
Therefore, you have 3.5/30.97 which is equal to 0.1130 mol Phosphorus. This is the amount of Phosphorus in moles in the fertilizer.</span>
