Answer:
a) 3.969
b) 3.489
Explanation:
a) Calculate the pk, value of the acid HA
PH of salt hydrolysis
P
= 1/2 ( pkw + pka + logC )
8.7 * 2 = 14 + log ( 0.27 ) + Pka
∴ Pka = 3.9686 ≈ 3.969
b) Calculate the PH of a solution containing 0.3 M HA and 0.1 M NaA
PH = Pka + log ( salt / acid )
= 3.9686 + log ( 0.1 / 0.3 )
= 3.9686 - 0.48 = 3.489
Answer:
87.54 g of H₂O₂
Explanation:
From the question given above, the following data were obtained:
Number of molecules = 1.55×10²⁴ molecules
Mass of H₂O₂ =.?
From Avogadro's hypothesis,
6.02×10²³ molecules = 1 mole of H₂O₂
Next, we shall determine the mass of 1 mole of H₂O₂. This can be obtained as follow:
1 mole of H₂O₂ = (2×1) + (2×16)
= 2 + 32
= 34 g
Thus,
6.02×10²³ molecules = 34 g of H₂O₂
Finally, we shall determine mass of H₂O₂ that contains 1.55×10²⁴ molecules. This can be obtained as follow:
6.02×10²³ molecules = 34 g of H₂O₂
Therefore,
1.55×10²⁴ molecules
= (1.55×10²⁴ × 34)/6.02×10²³
1.55×10²⁴ molecules = 87.54 g of H₂O₂
Thus, 87.54 g of H₂O₂ contains 1.55×10²⁴ molecules.
Answer:
covalent bonds
Explanation:
A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds and may result from the electrostatic force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds.
Answer:
The correct answer is density. See the explanation below, please.
Explanation:
Roland measured density, which is a property that relates mass to volume, having units for example: grams / cm3
