Which statement is true about writing chemical formulas of covalent compounds?

Response:

D.

Justification:

Answer:NH₃/NH₄Cl

Explanation:

The pH of a buffer can be determined using Henderson-Hasselbalch's equation.

When the concentration of acid equals that of the base, the pH aligns with the pKa of the buffer. The ideal pH range is pKa ± 1.

Below are the buffers and their corresponding pKa values:

• CH₃COONa/CH3COOH (pKa = 4.74)

• NH₃/NH₄Cl (pKa = 9.25)

• NaOCl/HOCl (pKa = 7.49)

• NaNO₂/HNO₂ (pKa = 3.35)

• NaCl/HCl Not a buffer

Thus, the ideal buffer is NH₃/NH₄Cl.

To determine the mass of salt using Avogadro's number, we find the moles of NaCl: 8.24x10²² molecules NaCl divided by 6.022x10²³ molecules NaCl per mole gives 0.14 mole NaCl. We can convert moles to grams of NaCl by multiplying 0.14 mole by 58g NaCl per mole, yielding a total of 8.12 g NaCl.

Answer:

Explanation:

Charge of one electron =

The formula for calculating charge is:

Given that: Charge =

Total electrons, n =

To determine the mass of AlF3 in 2.64 moles of AlF3, we use the formula: mass = moles x molar mass, which results in 221.76 grams of AlF3.