Answer:
True
Explanation:
Dispensing chemical from large stock bottles into smaller container makes sure that students only takes the quantity they need which reduces wastage. Also in situation where the students did not finish the reagent or chemical it is easier for student to pour back into smaller bottle than the entire reagent bottle which can contaminate the whole solution. Small bottles prevent or reduces the risk of spillage because it is easier to handle and pour.
Answer:
pH = 5.24
Explanation:
Mixture of acetic acid with acetate ion is a buffer (Mixture of a weak acid with its conjugate base). The pH of a buffer can be determined using Henderson-Hasselbalch equation:
pH = pKa + log₁₀ [A⁻] / [HA]
<em>Where pKa is -log Ka = 4.74; [A⁻] is the concentration of conjugate base (Acetate ion) and [HA] is molar concentration of the weak acid.</em>
Concentration of the acetic acid in the 100mL≡0.1L (76mL + 24mL) solution is:
[HA] = 0.024L ₓ (1mol / L) / 0.1L = 0.24M
[A⁻] = 0.076L ₓ (1mol / L) / 0.1L = 0.76M
Replacing in H-H equation:
pH = 4.74 + log₁₀ [0.76M] / [0.24M]
<h3>pH = 5.24</h3>
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