Answer:
2.67x10⁻¹⁴M = [OH-]
Step-by-step explanation:
To solve this question we need first to find the HCl concentration of the beaker 6. Then, using:
Kw = [OH-][H+]
Where Kw = 1x10⁻¹⁴
[OH-] is our incognite
[H+] is = [HCl]
Beaker 2 = 12.0M / 2 = 6.0M
Beaker 3 = 6.0M / 2 = 3.0M
Beaker 4 = 3.0M / 2 = 1.5M
Beaker 5 = 1.5M / 2 = 0.75M
Beaker 6 = 0.75M / 2 = 0.375M
HCl = 0.375M = [H+]
1x10⁻¹⁴ / [H+] = [OH-]
1x10⁻¹⁴ / 0.375M = 2.67x10⁻¹⁴M
2.67x10⁻¹⁴M = [OH-]