When analyzing the experiments: Rock candy formation occurs when excess sugar dissolves in hot water followed by crystallization. A student aims to create two rock candy batches. He discovers a box of "cane sugar" in the pantry. For batch A, he dissolves sugar in 500 mL of hot water at 70 degrees Celsius, continuing until no more dissolves. He then allows this solution to cool to room temperature. For batch B, he dissolves sugar in 500 mL of room temperature water until saturation, leaving it to sit.
a. It is probable that batch A will yield more rock candy.
b. It is probable that batch A will yield less rock candy.
c. It is likely that neither batch will yield any rock candy.
d. Additional information is needed to determine which batch is more likely to produce rock candy.
Answer: The correct option is A
Explanation:
Batch A should result in greater rock candy production since it utilizes hot water for dissolving sugar, while batch B will produce less due to the cooler temperature impacting solubility.
Hot water is essential for dissolving sugar more effectively than at room temperature. Sugar will dissolve until all available space for sugar molecules is filled.
Thus, the accurate response is Option A.
Response:
This is my understanding.
Explanation:
(g) Titration curves
While I can't create two curves on a single graph, I can depict them separately for clarity.
In part (d), the graph indicated an equivalence point at 20 mL.
For the second titration, since the NaOH concentration is doubled, the volume to reach the equivalence point will be halved — 10 mL.
Below are the two titration curves.
(h) Evidence of reaction
Both HCl and NaOH are colorless solutions.
There is no gas released or precipitate formed during their reaction.
It’s likely the student observed that the Erlenmeyer flask heated up, indicating a chemical change.
<span> </span><span>1. Other (Alcohol)
3. Acidic
5. Salt
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5060 has three significant figures: Below is the clarification
Explanation:
Significant figures
Significant figures (also referred to as significant digits and decimal places) in a number are those digits that carry substantial meaning.
These include all digits except: leading zeros.
Guidelines for determining significant figures
1. All non-zero digits are counted as significant. For instance, the number 23 has two significant figures.
2. Zeros located between two non-zero digits are significant; for example, 202.1201 contains seven significant figures.
3. Zeros preceding the significant figures are not significant. For example,.000021 has two significant figures, with zeros being non-contributory.
4. Zeros following the significant figures are significant.
This explains why the number 5060 has three significant figures.
