Oxygen had 6 valence electrons
Answer:
13.94moles of Na₂O
Explanation:
The balanced reaction expression is given as:
4Na + O₂ → 2Na₂O
Given parameters:
Number of moles of O₂ = 6.97moles
Unknown:
Number of moles of Na₂O
Solution:
To solve this problem;
1 mole of O₂ will produce 2 moles of Na₂O ;
6.97 moles of O₂ will produce 6.97 x 2 = 13.94moles of Na₂O
In a <u>Saturated </u>solution, the rate of dissociation equal to the rate of crystallization
Explanation:
A saturated solution is one than cannot dissolve any more solute because the solutes inter-molecular spaces are filled with the solute molecules at that temperature. When an attempt is made to dissolve more solute into the solution, the rate at which the solute is dissolved into the solution is equal to the rate at which excess solute is precipitated and crystallized.
pH is an important parameter for many reactions to take place in solution and in biological systems. It is related to the concentration of H⁺ ions through the following expression:
pH = 1/[H⁺] = -log [H⁺]
Wanting to know the pH of a solution is equivalent to knowing the amount of hydrogen ions present. But the pH scale is more convenient than the concentration scale because pH usually takes values between 0 and 14.
- When pH < 7 the solution is acid.
- When pH = 7 the solution is neutral (like pure water).
- When pH > 7 the solution is basic.
Answer:
10.4376 g
Explanation:
First we <u>calculate the sum of the weighings</u>:
- 10.4375 g + 10.4381 g + 10.4373 g + 10.4376 g = 41.7505 g
Then we <u>divide the sum by the number of weighings to calculate the average:</u>
- Average = Sum of weighings / Number of weighings
- 41.7505 g / 4 = 10.4376 g
