Answer:
A) Dilute the unknown so that it will have an absorbance within the standard curve. Once the diluted unknown concentration is determined, the full strength concentration can be calculated if the dilution process is recorded. Beer's law only applies to dilute solutions, so diluting the unknown is better than making new standards.
Explanation:
Beer's law states that <em>absorbance is proportional to the concentrations of the absorbing species</em>. This is verified in the case of diluted solutions (0≤0.01 M) of most substances. <u>As a solution gets more concentrated, solute molecules interact between themselves because of their proximity. </u>When a molecule interacts with another, the change in their electric properties (including absorbance) is probable. That's why <u>the plot of absorbance versus concentration stops being a straight line</u>, and <u>Beer's law is no longer valid.</u>
Therefore, if the absorbance value is higher than the highest standard, dilutions should be made. Once this concentration is determined, the full strength concentration can be calculated with the inverse of the dilution.
Answer:
1.88 × 10²² Molecules of CO
Explanation:
At STP for an ideal gas,
Volume = Mole × 22.4 L/mol
Or,
Mole = Volume / 22.4 L/mol
Mole = 0.7 L / 22.4 L/mol
Mole = 0.03125 moles
Now,
No. of Molecules = Moles × 6.022 × 10²³ Molecules/mol
No. of Molecules = 0.03125 × 6.022 × 10²³ Molecules/mol
No. of Molecules = 1.88 × 10²² Molecules of CO
K₃PO₄ → 3K⁺ (aq) + PO₄³⁻(aq)
One mole of PO₄³⁻ ion gets dissociated from one mole of K₃PO₄
As per the definition of Avogadro's number, 1 mole = 6.022 x 10²³ ions
One mole of PO₄³⁻ ions x (6.022 x 10²³ ions/ 1 mole of PO₄³⁻ ions )
= 6.022 x 10²³ ions
Therefore , there are 6.022 x 10²³ PO₄³⁻ ions in a mole of K₃PO₄.
False. Chemical products are on the right side.
