There are eight protons in an Oxygen's nucleus.
Answer:
The balanced equation tells us that 1 mole of Zn will produce 1 mole of H2.
1.566 g Zn x (1 mole Zn / 65.38 g Zn) = 0.02395 moles Zn
0.02395 moles Zn x (1 mole H2 / 1 mole Zn) = 0.02395 moles H2 produced
Now use the ideal gas law to find the volume V.
P = 733 mmHg x (1 atm / 760 atm) = 0.964 atm
T = 21 C + 273 = 294 K
PV = nRT
V = nRT/ P = (0.02395 moles H2)(0.0821 L atm / K mole)(294 K) / (0.964 atm) = 0.600 L
Answer:
The effective nuclear charge for a valence electron in oxygen atom: 
Explanation:
Effective nuclear charge ![[Z_{eff}]](https://tex.z-dn.net/?f=%5BZ_%7Beff%7D%5D)
is the net nuclear charge experienced by the electron in a given atom. It is always less than the actual charge of the nucleus [Z], due to shielding by electrons in the inner shells.
<em>It is equal to the difference between the actual nuclear charge or the atomic number (Z) and the shielding constant (s). </em>
<u>For an oxygen atom</u>-
Electron configuration: (1s²) (2s² 2p⁴)
<em>The atomic number (actual nuclear charge): </em>Z = 8
The shielding constant (s) for a valence electron can be calculated by using the Slater's rules:
⇒ s = 5 × 0.35 + 2 × 0.85 = 1.75 + 1.7 = 3.45
<u><em>Therefore, the effective nuclear charge for a valence electron in oxygen atom is:</em></u>
<u>Therefore, the effective nuclear charge for a valence electron in oxygen atom:</u>
Explanation:
look in the picture for the answer
Answer:
through natural selection
Explanation:
Natural selection is the driving mechanism of the evolution of species. Organisms can survive more in an environment if they are capable to adapt the changing environmental conditions. After surviving they are also able to pass their modified trait into their future generations (evolution).
Helpful variations accumulate through natural selection, as the organisms that are better adapted to their environment reproduce offspring with the same variations.
