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chemistry is novel to me but id like to become knowledgeable
The deterimination of the mole
Avogadro’s number (6.02214076×10^23) was determined as the number of atoms in 12 grams of carbon-12. Since this number is a mole, 1 mole of carbon weighs 12 grams. Because of this, you can notice that the atomic mass of some lighter element is sometimes the atomic number (proton number) multiplied by two due to equal neutrons.
Protons and neutrons
Protons repel eachother – and neutrons add mass to the nucleus that helps to hold the protons together. Hydrogen is the only element that usually has more protons than neutrons, for there is no repelling force with a singular proton. With the elements of higher atomic number, neutrons outnumber the protons substantially in order to stabilize the nucleus.
Protons are sometimes referred to as H+, for hydrogen typically has 1 proton and zero neutrons, and if missing an electron, it is a proton. Mass of protons is slightly less than neutrons, and 1836 times the mass of electrons.
Electrons
Electrons are attracted to the protons of the nucleus yet repel eachother, and due to these factors form a cloud around the nucleus with a complex pattern of layers based on energy conservation and quantum priniciples. It is the valence (outermost) electrons that are critical for chemical bonding compatibility. Electrons are thought to exist with probabilistic locations. A pair is two electrons of the same oribital with opposite spins. The opposite spin is theoretically explained in that two identical fermions in the same location (in this case their orbital) out to be distinguished by different quantum states (Pauli exclusion principle).
Ionic charge
The charge of an ion is caused by a difference in the number of protons and electrons. The valence orbital has a certain amount of electrons it can and wants to hold. The valence orbital can have a capacity of 2, 8, 16, 32 (2n^2) depending on the element. Elements tend to lose or gain valence electrons in order to not have an incomplete valence orbital. Of course, loss or gain of electrons makes it a cation or anion, respectively.
Chemical equillibrium and Le Chatelier’s principle
Equillibrium is when reversible reactions occur bothways at equal rates; it is a chemically dynamic but proportionately equal state. Le Chatelier’s principle is that when a factor (quantity of molecules, temperature, pressure) is changed, a new equillibrium is reached. In other words, disruption is offset by a compensatory result that leads to balance, albeit a different balance that is adjusted for the conditionary change. An explanatory model for a general reversable synthesis reaction: If additional reactant A is added, then the product will increase, and reactant B will decrease – this will be the new equillibrium.
pH and acids and bases
The standard formula for pH is -log[H+], where H+ is hydrogen ions in mol/L. Because it is logarithmic (with a base of 10), each unit of pH is different 10-fold from the next. pH of 4 is 10 times as acidic as pH 5.
How to think about the atom
The most important is the number of protons, for that variation is what accounts for the variety of elements. Electrons repel electrons and protons repel protons. The mass is concentrated in the nucleus, and despite protons repelling eachother, the weight of the neutrons holds the protons together. It makes sense that the valence electrons are what has the critical influence on interactions between atoms, for it is just like how the outer surfaces of other objects interact with eachother. Electrons are thought of as existing in probability clouds around the nucleus.
Polarity and electronegativity
Polarity is when one end of a compound is significantly more electronegative than the other. Electronegativity is a measure of how much an atom wants to pull in shared electrons. It is the shared electrons primarily that are shifted toward the more electronegative atom. The electron cloud being shifted to one end creates a negative pole.
Not all compounds are polar. Of course, molecules like H2, F2, etc. are nonpolar as both atoms are the same element and thus have the same electronegativity. Carbon-hydrogen bonds are another notable example of nonpolar bonds.
The cause of electronegativity is the protons in the nucleus, because of course electrons are attracted to protons. Yet it's not so simple as more protons -> more electronegativity, as the more electron shells an atom has, the greater the distance from the protons the shared electrons would be. By combining the factors of proton number and electron shell number, you can notice the pattern of electronegativity on the periodic table.
The most electronegative atoms are F (3.98), O (3.44), Cl (3.16), N (3.04), Br (2.96), I (2.66), S (2.58), Se (2.55), P (2.19), measured in Pauling scale.
Chirality
Some chemical compounds have multiple possible arrangements, despite being the same compound. These are called enantiomers Usually, there are two variants, but there are exponentially more with more than one chiral center.
In this example, the carbon is the chiral center. You can see that if these two compounds were oriented in the same way, they would not be the same, but be mirror-images of eachother.
Intriguingly, biological compounds are usually produced with a specific handedness. Synthetic chemical methods produce equal ratios, which is called racemic.
The deterimination of the mole
Avogadro’s number (6.02214076×10^23) was determined as the number of atoms in 12 grams of carbon-12. Since this number is a mole, 1 mole of carbon weighs 12 grams. Because of this, you can notice that the atomic mass of some lighter element is sometimes the atomic number (proton number) multiplied by two due to equal neutrons.
Protons and neutrons
Protons repel eachother – and neutrons add mass to the nucleus that helps to hold the protons together. Hydrogen is the only element that usually has more protons than neutrons, for there is no repelling force with a singular proton. With the elements of higher atomic number, neutrons outnumber the protons substantially in order to stabilize the nucleus.
Protons are sometimes referred to as H+, for hydrogen typically has 1 proton and zero neutrons, and if missing an electron, it is a proton. Mass of protons is slightly less than neutrons, and 1836 times the mass of electrons.
Electrons
Electrons are attracted to the protons of the nucleus yet repel eachother, and due to these factors form a cloud around the nucleus with a complex pattern of layers based on energy conservation and quantum priniciples. It is the valence (outermost) electrons that are critical for chemical bonding compatibility. Electrons are thought to exist with probabilistic locations. A pair is two electrons of the same oribital with opposite spins. The opposite spin is theoretically explained in that two identical fermions in the same location (in this case their orbital) out to be distinguished by different quantum states (Pauli exclusion principle).
Ionic charge
The charge of an ion is caused by a difference in the number of protons and electrons. The valence orbital has a certain amount of electrons it can and wants to hold. The valence orbital can have a capacity of 2, 8, 16, 32 (2n^2) depending on the element. Elements tend to lose or gain valence electrons in order to not have an incomplete valence orbital. Of course, loss or gain of electrons makes it a cation or anion, respectively.
Chemical equillibrium and Le Chatelier’s principle
Equillibrium is when reversible reactions occur bothways at equal rates; it is a chemically dynamic but proportionately equal state. Le Chatelier’s principle is that when a factor (quantity of molecules, temperature, pressure) is changed, a new equillibrium is reached. In other words, disruption is offset by a compensatory result that leads to balance, albeit a different balance that is adjusted for the conditionary change. An explanatory model for a general reversable synthesis reaction: If additional reactant A is added, then the product will increase, and reactant B will decrease – this will be the new equillibrium.
pH and acids and bases
The standard formula for pH is -log[H+], where H+ is hydrogen ions in mol/L. Because it is logarithmic (with a base of 10), each unit of pH is different 10-fold from the next. pH of 4 is 10 times as acidic as pH 5.
How to think about the atom
The most important is the number of protons, for that variation is what accounts for the variety of elements. Electrons repel electrons and protons repel protons. The mass is concentrated in the nucleus, and despite protons repelling eachother, the weight of the neutrons holds the protons together. It makes sense that the valence electrons are what has the critical influence on interactions between atoms, for it is just like how the outer surfaces of other objects interact with eachother. Electrons are thought of as existing in probability clouds around the nucleus.
Polarity and electronegativity
Polarity is when one end of a compound is significantly more electronegative than the other. Electronegativity is a measure of how much an atom wants to pull in shared electrons. It is the shared electrons primarily that are shifted toward the more electronegative atom. The electron cloud being shifted to one end creates a negative pole.
Not all compounds are polar. Of course, molecules like H2, F2, etc. are nonpolar as both atoms are the same element and thus have the same electronegativity. Carbon-hydrogen bonds are another notable example of nonpolar bonds.
The cause of electronegativity is the protons in the nucleus, because of course electrons are attracted to protons. Yet it's not so simple as more protons -> more electronegativity, as the more electron shells an atom has, the greater the distance from the protons the shared electrons would be. By combining the factors of proton number and electron shell number, you can notice the pattern of electronegativity on the periodic table.
The most electronegative atoms are F (3.98), O (3.44), Cl (3.16), N (3.04), Br (2.96), I (2.66), S (2.58), Se (2.55), P (2.19), measured in Pauling scale.
Chirality
Some chemical compounds have multiple possible arrangements, despite being the same compound. These are called enantiomers Usually, there are two variants, but there are exponentially more with more than one chiral center.
In this example, the carbon is the chiral center. You can see that if these two compounds were oriented in the same way, they would not be the same, but be mirror-images of eachother.
Intriguingly, biological compounds are usually produced with a specific handedness. Synthetic chemical methods produce equal ratios, which is called racemic.
