Answer:
ZcH's electrons = 5-2 = +3.
ZcH for inner electrons = -5 - 0 = +5.
Explanation:
Boron 1s² 2s² 2p
As, 2s ⇒ 2.58.
2p ⇒ 2.42.
Electrons = +3.
Greater than 2 cm = 0.35
Slightly greater than +3 .
The most accurately represented John Dalton's model of the atom is: C. a tiny, solid sphere with a predictable mass for a given element
<h3>Further explanation</h3>
The development of atomic theory starts from the first term conveyed by Greek scientists who suggested that every substance has the smallest particles so that the word atomos appears, which means it cannot be divided. So, John Dalton, a British scientist put forward the hypothesis about atoms, among others:
- 1. The elements are composed of atoms which are small particles which cannot be subdivided
- 2. Atoms that make up the same element have the same properties, mass, and size, while for different elements, the properties are also different
- 3. Compounds are composed of two or more atoms in a fixed ratio
- 4. In chemical reactions, atoms after and before a reaction cannot be destroyed, only separation and reassembly occur
Point 3 shows the relationship with The Law of Constant Composition of Proust so that further research on atoms is more developed
Dalton's hypothesis is described as a solid sphere like a very small shot put ball or a bowling ball based on Dalton's hobby in bowling
<h3>Learn more</h3>
Bohr's model of the atom
brainly.com/question/1625635
Rutherford performed the gold foil experiment
brainly.com/question/1859083
The part of an atom that is mostly empty space
brainly.com/question/4089014
Keywords: atom, Dalton, a solid sphere, The Law of Constant Composition
Answer:
The group 15 elements: the pnicogens
Explanation:
The group 15 elements, nitrogen, phosphorus, arsenic, antimony and bismuth, all have the general valence shell electronic configuration ns2np3. They can all exist in the +3 or +5 oxidation state, with the +3 state increasing in stability as we move vertically down the group.
Answers and Explanation:
a)- The chemical equation for the corresponden equilibrium of Ka1 is:
2. HNO2(aq)⇌H+(aq)+NO−2
Because Ka1 correspond to a dissociation equilibrium. Nitrous acid (HNO₂) losses a proton (H⁺) and gives the monovalent anion NO₂⁻.
b)- The relation between Ka and the free energy change (ΔG) is given by the following equation:
ΔG= ΔGº + RT ln Q
Where T is the temperature (T= 25ºc= 298 K) and R is the gases constant (8.314 J/K.mol)
At the equilibrium: ΔG=0 and Q= Ka. So, we can calculate ΔGº by introducing the value of Ka:
⇒ 0 = ΔGº + RT ln Ka
ΔGº= - RT ln Ka
ΔGº= -8.314 J/K.mol x 298 K x ln (4.5 10⁻⁴)
ΔGº= 19092.8 J/mol
c)- According to the previous demonstation, at equilibrium ΔG= 0.
d)- In a non-equilibrium condition, we have Q which is calculated with the concentrations of products and reactions in a non equilibrium state:
ΔG= ΔGº + RT ln Q
Q= ((H⁺) (NO₂⁻))/(HNO₂)
Q= ( (5.9 10⁻² M) x (6.7 10⁻⁴ M) ) / (0.21 M)
Q= 1.88 10⁻⁴
We know that ΔGº= 19092.8 J/mol, so:
ΔG= ΔGº + RT ln Q
ΔG= 19092.8 J/mol + (8.314 J/K.mol x 298 K x ln (1.88 10⁻⁴)
ΔG= -2162.4 J/mol
Notice that ΔG<0, so the process is spontaneous in that direction.
