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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 repel eachother. A pair is two electrons with opposite spins.
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.
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 repel eachother. A pair is two electrons with opposite spins.
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.
