Answer:
Given that camphor is a sublime material while sand is not, a gradual heating of the mixture allows for the separation of camphor from sand. The camphor vapors can then be collected and allowed to cool. This process will result in the formation of solid camphor crystals.
Explanation:
Answer: second option: 1.70 to 1.40
Explanation:
1) pH is defined using the formula pH = - log [H₃O⁺]
2) Given that the initial concentration is x and after doubling it becomes 2x, we calculate:
pHi = - logx
pHf = - log 2x = - log 2 - logx
Thus, pHf - pHi = - log2 - logx - (- logx) = - log2 ≈ - 0.30
⇒ pHi - pHf = 0.30, indicating that the final pH (with twice the hydronium ions) is 0.30 lower than the starting pH.
3) The only option that indicates a 0.30 decline in pH is the second one: from 1.70 to 1.40. Therefore, that is the correct choice.
The true statement is B. With identical masses for both metals, the final temperature of the two will be more aligned with 498 K rather than 298 K, as iron's specific heat capacity is significantly greater than that of gold's.
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.
