Answer:
The correct answer is 574.59 grams.
Explanation:
Based on the given information, the number of moles of NH₃ will be,
= 2.50 L × 0.800 mol/L
= 2 mol
The given pH of a buffer is 8.53
pH + pOH = 14.00
pOH = 14.00 - pH
pOH = 14.00 - 8.53
pOH = 5.47
The Kb of ammonia given is 1.8 * 10^-5. Now pKb = -logKb,
= -log (1.8 ×10⁻⁵)
= 5.00 - log 1.8
= 5.00 - 0.26
= 4.74
Based on Henderson equation:
pOH = pKb + log ([salt]/[base])
pOH = pKb + [NH₄⁺]/[NH₃]
5.47 = 4.74 + log ([NH₄⁺]/[NH₃])
log([NH₄⁺]/[NH₃]) = 5.47-4.74 = 0.73
[NH₄⁺]/[NH₃] = 10^0.73= 5.37
[NH₄⁺ = 5.37 × 2 mol = 10.74 mol
Now the mass of dry ammonium chloride required is,
mass of NH₄Cl = 10.74 mol × 53.5 g/mol
= 574.59 grams.
About 0.92 kg of benzyl salicylate would be needed in order to manufacture 325 tubes of sunscreen.
A tube contains 4.0 oz of the sunscreen and each one 2.5% benzyl salicylate.
2.5% of 4.0 oz = 0.1 oz
Thus, each tube would need 0.1 oz of benzyl salicylate.
325 tubes of the sunscreen is needed and each one requires 0.1 oz of benzyl salicylate. Hence, total amount of benzyl salicylate needed would be:
325 x 0.1 oz = 32.5 oz
From conversion:
16 oz = 1 lb
Hence,
32.5 oz = 32.5/16
= 2.03 lb
Also:
2.205 lb = 1 kg
2.03 lb = 2.03/2.205
= 0.92 kg
More on dimensional analysis can be found here: brainly.com/question/22015862
Answer:
Volume of acid in the solution, 53.87 mL
Explanation:
This can be solved with a simple formula
(Volume of solution which is acid / Total volume) . 100 = % acid
(Volume of solution which is acid / 341 mL) . 100 = 15.8
Volume of solution which is acid / 341 mL = 0.158
Volume of solution which is acid = 0.158 . 341 mL
Volume of solution which is acid = 53.87 mL
Answer:
Ionic solid.
Explanation:
Ionic solid dissociated into free ions capable of conducting electricity in aqueous solution. Ionic solids are also characterised by high melting point due to strong ionic bonds. No free ions or electrons to conduct electricity in solid form.
