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>
Germanium is classified as a metalloid.
Answer:
<em>Minerals are naturally occurring inorganic solids with a crystalline structure and a definite range of chemical formula. Ores are concentrations of minerals in rock that are high enough to be economically extracted for use. All ores are minerals, but all minerals are not necessarily ores.</em>
Hope its helpful!
We are going to use this formula:
E° = 0.0592/ n * ㏒K
when E° is the standard state cell potential
and n is number of moles of electrons transferred in the balanced equation
for the reaction of the cell.
Sr(s) + Mg2+ (aq) ↔ Sr2+(aq) + Mg(s)
we can get it by using the given balanced equation, we here have 2 electrons
transferred so, n = 2
and K the equilibrium constant = 3.69 x 10^17
so, by substitution:
∴ E° = 0.0592 / 2 * ㏒ (3.69 x 10^17)
= 0.52 V
Answer:
119 protons and 179 neutrons
Explanation:
Given an element of the form AB-298, we know that 298 is the mass, which means it's the sum of the number of protons and number of neutrons.
Look at the answer choices and find the one whose numbers add up to 298. Only C (119 protons and 179 neutrons) is correct because 119 + 179 = 298.
Hope this helps!
