Answer:
5.56 × 10⁻⁸
Explanation:
Step 1: Given data
- Concentration of the weak acid (Ca): 0.187 M
Step 2: Calculate the concentration of H⁺
We will use the following expression.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -3.99 = 1.02 × 10⁻⁴ M
Step 3: Calculate the acid dissociation constant (Ka)
We will use the following expression.
![Ka = \frac{[H^{+}]^{2} }{Ca} = \frac{(1.02 \times 10^{-4})^{2} }{0.187} = 5.56 \times 10^{-8}](https://tex.z-dn.net/?f=Ka%20%3D%20%5Cfrac%7B%5BH%5E%7B%2B%7D%5D%5E%7B2%7D%20%7D%7BCa%7D%20%3D%20%5Cfrac%7B%281.02%20%5Ctimes%2010%5E%7B-4%7D%29%5E%7B2%7D%20%7D%7B0.187%7D%20%3D%205.56%20%5Ctimes%2010%5E%7B-8%7D)
Answer: b. The waste generated is hazardous and must be disposed of.
c. Nuclear material can be spilled into the ocean if reactors are near the coast.
d. A large amount of cold water is generated, which must be stored somewhere.
Explanation:
The main environmental costs for produced during the nuclear power plant consists of procurement of fuel and the thermal load is also produced with cold water discharge in the sea. This can contaminate the sea, hence, must be stored somewhere. The nuclear waste consists of radioactive substances which are hazardous for the environment. The nuclear based electricity does not produce carbon dioxide.
The metal component of the given compound, CrCl3, is chromium. The number of moles per 1 g of chromium is calculated through the equation below,
n = (1 g Cr)(1 mol Cr/51.996 g Cr)
n = 0.0192 mol Cr(3 electrons/1 mol Cr)
n = 0.0577 e-
Determine the number in charge by multiplying with Faraday's constant,
C = (0.0577 mol Cr)((1 F/1 mol e-)(96485 C/ 1F)
C = 5,566.87 C
Then, calculate time by dividing the charge with the current,
t = 5566.87 C/1.5 A
t = 3711.25 minutes
t = 61.84 hours
<span><em>Answer: 61.84 hours</em></span>
