Answer: 25,200.
Explanation:
1) Starting with: 4.659 × 10⁴ - 2.14 × 10⁴
2) Significant figures need to be considered.
Because the powers are equal (10⁴), the decimal values can be subtracted directly. However, it is essential to first check significant figures and the count of decimal places.
3) The figure 4.659 × 10⁴ has four significant digits (4, 6, 5, and 9), whereas 2.14 × 10⁴ contains three significant digits (2, 1, and 4).
4) When adding or subtracting values with a different number of decimal places, the answer must reflect the same number of decimal places as the number with the least amount of decimal precision.
5) Prior to performing subtraction, it is necessary to round the numbers to the least decimal places. Given that 2.14 has two decimal places and 4.659 has three, round 4.659 to 4.66.
6) Now perform the subtraction 4.66 - 2.14 = 2.52
7) Then multiply by the power of 10: 2.52 × 10⁴ = 25,200. This is the final answer.
The pH level is 1.39. To explain, we start with the given information: the concentration of HClO is 0.15 M, with an acid dissociation constant of 2.9 × 10-8. The objective is to calculate the pH of the solution. Through the process, we find that the equilibrium concentration after applying the formula yields 0.04069 M for H3O⁺, leading us to a pH of 1.39.
62.0g divided by 125g equals 0.496, then multiplied by 100 gives 49.6%.
Answer:
Can you rank the following chemical substances in order of their absolute entropies (So) from lowest (1) to highest (5) at a temperature of 298 K?
a. Al (s)
b. H2O (l)
c. HCN (g)
d. CH3COOH (l)
e. C2H6 (g)
Explanation:
Entropy quantifies the level of disorder within a system.
In solids, the entropy is significantly lower compared to liquids and gases.
The typical order of entropy is:
solids < liquids < gases
In the substances listed, liquid water notably exhibits strong intermolecular hydrogen bonding.
This results in water having comparatively lower entropy.
Next in line is acetic acid.
Among the gaseous components, ethane has higher entropy than HCN due to its weaker intermolecular interactions.
HCN involves some hydrogen bonding.
Thus, the order of entropy is:
Al(s) < CH3COOH (l) < H2O(l) < HCN(g) < C2H6(g)
