Zeff = Z - S
Here, Z is the number of protons in the nucleus, that is, atomic number, and S is the number of nonvalence electrons.
For boron, the electronic configuration is 1s₂ 2s₂ 2p₄
Z = 5, S = 2
Zeff = 5-2 = +3
For O, electronic configuration is 1s₂ 2s₂ 2p₄
Z = 8, S = 2
Zeff = 8-2 = +6
Hence, the correct answer is second option, that is, +3 and +6, the Zeff of boron is smaller in comparison to O, thus, boron exhibits a bigger size than O.
Answer:
pH = 12.65
Explanation:
From the given information:
number of moles =mass in gram / molar mass
number of moles of KOH = mass of KOH / molar mass of KOH
number of moles of KOH = 0.251 g / 56.1 g/mol = 0.004474 mol
For solution :
number of moles = Concentration × volume
concetration = number of moles/ volume
concetration = 0.004474 mol / 0.100 L
concetration = 0.04474 M
We know that 1 moles KOH result into 1 mole OH⁻ ions
Therefore, Molarity of OH⁻ = 0.04474 M
Now,
pOH = -log[OH⁻]
pOH = -log (0.04474) M
pOH = 1.35
Similarly,
pH + pOH = 14
pH = 14 - pOH
pH = 14 - 1.35
pH = 12.65
The speed is 7,350km that's the speed of the car
Answer:
Approximately 5.646 * 10^-17 moles
Explanation:
Avagardo's number is approximately 6.022 * 10^23 molecules. Therefore, dividing 3.4 * 10^7 by avagadro's number yields approximately 5.646 * 10^-17 moles. Hope this helps