Answer:
1.7 mL
Explanation:
<em>A chemist must prepare 550.0 mL of hydrochloric acid solution with a pH of 1.60 at 25 °C. He will do this in three steps: Fill a 550.0 mL volumetric flask about halfway with distilled water. Measure out a small volume of concentrated (8.0 M) stock hydrochloric acid solution and add it to the flask. Fill the flask to the mark with distilled water. Calculate the volume of concentrated hydrochloric acid that the chemist must measure out in the second step. Round your answer to 2 significant digits.</em>
Step 1: Calculate [H⁺] in the dilute solution
We will use the following expresion.
pH = -log [H⁺]
[H⁺] = antilog - pH = antilog -1.60 = 0.0251 M
Since HCl is a strong monoprotic acid, the concentration of HCl in the dilute solution is 0.0251 M.
Step 2: Calculate the volume of the concentrated HCl solution
We want to prepare 550.0 mL of a 0.0251 M HCl solution. We can calculate the volume of the 8.0 M solution using the dilution rule.
C₁ × V₁ = C₂ × V₂
V₁ = C₂ × V₂/C₁
V₁ = 0.0251 M × 550.0 mL/8.0 M = 1.7 mL
Answer:
ii. < iv. < i. < iii.
Explanation:
Hello,
At first, the entropy is lower in solid-phase systems since their particles are molecularly closer. Next, by knowing that the higher the temperature, the higher the entropy, the gaseous HCl at 25 ºC occupies the second place. After that, it is clear 2 moles of HCl have more entropy than just 1 since the larger the amount of mater the higher the entropy.
Best regards.
<h3>
Answer:</h3>
79.8 ml
<h3>
Explanation:</h3>
Boyle's law describes the relationship between pressure and volume when the temperature is constant. For this question, I will be rounding to significant figures.
Boyle's Formula
When describing the relationship between pressure and volume, the formula
. In this formula,
is the initial pressure and volume. On the other side,
is final pressure and volume. So, to find a missing variable you must plug in the values you are given.
Final Volume
Remember when solving this question to remain constant in your units. When we plug in the values we know we are given:
Now, we can multiply the left side
Finally, we can divide by 385 to isolate the final volume
This gives the final volume of 79.8mL.
Answer:
The electron spends a lot of time away from hydrogen and hydrogen's nucleus is exposed for
interaction
Explanation:
I got the question right
Answer:
1.62 × 10⁴ cal
Explanation:
Step 1: Given and required data
- Mass of water (m): 30.0 g
- Latent heat of vaporization of water (ΔH°vap): 540 cal/g
Step 2: Calculate the heat change (Q) for vaporization of 30.0g of water at 100 °C
The vaporization is a phase change in which water passes from the liquid state to the gaseous state. We can calculate the heat required using the following expression.
Q = ΔH°vap × m
Q = 540 cal/g × 30.0 g
Q = 1.62 × 10⁴ cal