Answer:
Option 1, Cl is reduced and gains electrons
Explanation:
HClO₃ → HClO₂
In HClO₃, chlorine acts with +5 in the oxidation state
In HClO₂,, chlorine acts with +3 in the oxidation state.
The state has been reducted, so the Cl has been reduced. As it was reduced, it means that has won e⁻, in this case 2
Cl⁻⁵ → Cl⁻³ + 2e⁻
<span> The atomic number increases by one and the element becomes a different element. </span>
Assuming the concentration of stock solution is 50% sodium phosphate buffer solution, the volume of stock solution required is 6 mL and the volume of water required is 6 mL.
<h3>What volume of a stock Sodium phosphate buffer and water is needed to 12 mL of 25% sodium phosphate buffer of pH 4?</h3>
The process of preparing solutions from stock solutions of higher concentration is known as dilution.
Dilution is done with the aid of the dilution formula given below:
where
- C1 is the concentration of stock solution
- V1 is the volume of stock solution required to prepare a diluted solution
- C2 is the concentration of the diluted solution prepared
- V2 is the final volume of the diluted solution
From the data provided:
C1 is not given
V1 is unknown
C2 = 25%
V2 = 12 mL
- Assuming C1 is 50% solution
Volume of stock, V1, required is calculated as follows:
V1 = C2V2/C1
V1 = 25 × 12 /50
V1 = 6 mL
Therefore, the volume of stock solution required is 6 mL and the volume of water required is 6 mL.
Learn more about dilution formula at: brainly.com/question/7208546
Answer:
B
Explanation:
Noble gases are in group 18 (neon, argon, etc)
Answer: An electron having a quantum number of one is closer to the nucleus
Explanation:
The Bohr model relies on electrostatic attraction between the nucleus and orbital electron. Hence, the closer an electron is to the nucleus the more closely it is held by the nucleus and the lesser its energy (the more stable the electron is and the more difficult it is to ionize it). The farther an electron is from the nucleus ( in higher shells or energy levels), the less the electrostatic attraction of such electron to the nucleus due to shielding effect. Hence it is less tightly held.
