You prepared the buffer by adding about 0.2 g of each of the weak acid and its conjugate base to 25.0 mL of water. The goal was

Response:

0.8853 mL

Clarification:

Initially, we convert 13 lb to kg, remembering that 1 lb = 0.454 kg:

• 13 lb * = 5.902 kg

Next, we determine the required mg of acetaminophen to administer, applying the recommended dosage and infant's weight:

• 15 mg/kg * 5.902 kg = 88.53 mg

Finally, we compute the necessary mL of suspension, utilizing its concentration:

• 88.53 mg ÷ (80 mg/0.80 mL) = 0.8853 mL

From the provided data, the unknown mixture was composed of salt, salicylic acid, and sand. It is understandable that the student suspected the presence of sand, yet scientific experimentation must verify such assumptions. The test involving salt and salicylic acid reveals that salt dissolves in water, while salicylic acid is only slightly soluble, and sand does not dissolve at all. By introducing the unknown into water, the salt would dissolve first, followed by the partial dissolution of salicylic acid. Heating the mixture could allow for the evaporation of salicylic acid, resulting in the remaining salt. If traces of sand were observed in the dissolved sample, it could suggest contamination.

Response: The rate constant at 525 K is,

Rationale:

Based on the Arrhenius equation,

or,

where,

= rate constant when =

= rate constant when =?

= activation energy for the process =

R = gas constant = 8.314 J/mole.K

= initial temperature = 701 K

= final temperature = 525 K

Substituting the provided values into this formula yields:

Thus, the rate constant at 525 K is,

Based on the equation:

ΔG = ΔH - TΔS = 0

It follows that ΔS = ΔH/T

So, ΔS = n*ΔHVap / Tvap

- where n represents the number of moles calculated as mass/molar mass

For a mass of 24.1 g

and a molar mass of 187.3764 g/mol

substituting gives:

∴ n = 24.1 / 187.3764g/mol

      = 0.129 moles

The molar enthalpy of vaporization, ΔHvap, is 27.49 kJ/mol

The temperature in Kelvin, Tvap = 47.6 + 273 = 320.6 K

After substitution, we compute ΔS, the change in entropy:

∴ΔS = 0.129 mol * 27490 J/mol / 320.6 K

      = 11 J/K

The density is 1.03 g/cm³. Explanation: The density of a substance is calculated with the formula: 1 kg = 1000 g therefore 2.06 kg = 2060 g. 1 L = 1000 cm³ thus 2 L = 2000 cm³. We now find: Mass = 2060 g Volume = 2000 cm³. Thus, the final answer of density is: 1.03 g/cm³. I hope this information assists you.