35 ka table

Main article: This timeline shows the whole years ago, that is, Each row corresponds to a change in log (time before present, that is, the logarithm of the time before the present) of about 0.1 (using base 10 logarithm). The dividing points are taken from the R′′20 The table is divided into sections with subtitles. Note that each such section contains about 68% of all the time from the beginning of the section until now. Past [ ] Visual timelines including ages The following five timelines show the geologic time scale to scale. The first shows the entire time from the formation of the Earth to the present, but this gives little space for the most recent eon. The second timeline shows an expanded view of the most recent eon. In a similar way, the most recent era is expanded in the third timeline, the most recent period is expanded in the fourth timeline, and the most recent epoch is expanded in the fifth timeline. Millions of Years (1st, 2nd, 3rd, and 4th) Thousands of years (5th) 13,800 million years ago to 5,500 million years ago [ ] Time interval, before the present time. a= Event, invention or historical development 13.8 11 Ga – 9 Ga Formation of the 9 Ga – 7 Ga Formation of the earliest 7 Ga – 5.5 Ga Formation of the exoplanets 5,500 million years ago to 1,800 million years ago [ ] Time interval, before the present time. a= Event, invention or historical development 5.5 Ga – 4.5 Ga Pre- The dark-energy dominated era starts after the 4.5 Ga – 3.5 Ga beginning of Formati...

Ka Table Acid Ionization Constants at 25 °C. Acid Formula K a HC 2H 3O 2 1.8×10 –5 Acrylic acid HC 3H 3O 2 5.5×10 –5 Aluminum 3+ ion Al 3+( aq) 1.4×10 –5 Ammonium ion NH 4 + 5.6×10 –10 Anilinium ion C 6H 5NH 3 + 1.4×10 –5 Arsenic acid H 3AsO 4 6.0×10 –3 H 2AsO 4 – 1.0×10 –7 HAsO 4 2– 3.2×10 –12 Arsenous acid H 3AsO 3 6.6×10 –10 Ascorbic acid H 2C 6H 6O 6 6.8×10 –5 HC 6H 6O 6 – 2.8×10 –12 Bromoacetic acid HC 2H 2BrO 2 1.3×10 –3 Benzoic acid HC 7H 5O 2 6.3×10 –5 Beryllium 2+ ion Be 2+( aq 3×10 –7 Boric acid H 3BO 3 5.9×10 –10 Butyric acid HC 4H 7O 2 1.5×10 –5 Carbonic acid H 2CO 3 4.4×10 –7 HCO 3 – 4.7×10 –11 Chloroacetic acid HC 2H 2ClO 2 1.4×10 –3 Chlorous acid HClO 2 1.1×10 –2 Chromic acid H 2CrO 4 1.5×10 –1 HCrO 4 – 3.2×10 –7 Chromium 3+ ion Cr 3+( aq) 6.6×10 –4 Citric acid H 3C 6H 5O 7 7.4×10 –4 H 2C 6H 5O 7 – 1.7×10 –5 HC 6H 5O 7 2– 4.0×10 –7 Cobalt 2+ ion Co 2+( aq) 1.3×10 –9 Codeine ammonium ion HC 18H 21O 3N + 1.1×10 –8 Cyanic acid HOCN 3.5×10 –4 Dichloroacetic acid HC 2HCl 2O 2 5.5×10 –2 Diethylammonium ion (C 2H 5) 2NH 2 + 1.4×10 –11 Dimethylammonium ion (CH 3) 2NH 2 + 1.7×10 –11 Ethylammonium ion C 2H 5NH 3 + 2.3×10 –11 Ethylenediammonium ion NH 2CH 2CH 2NH 3 + 1.9×10 –11 Fluoroacetic acid HC 2H 2FO 2 2.6×10 –3 Formic acid HCHO 2 1.8×10 –4 Hydrazinium ion N 2H 5 + 1.2×10 –8 Hydrazoic acid HN 3 1.9×10 –5 Hydrocyanic acid HCN 6.2×10 –10 Hydrofluoric acid HF 6.6×10 –4 Hydrogen peroxide H 2O 2 2.2×10 –12 Hydrogen selenate ion HSeO 4 – 2.2×10 –2 HSO 4 – 1.1×10 –2 Hydr...

\( \newcommand\) • • • • • • • • • • • • • • \(K_a\) is an acid dissociation constant, also known as the acid ionization constant. It describes the likelihood of the compounds and the ions to break apart from each other. As we already know, strong acids completely dissociate, whereas weak acids only partially dissociate. A big \(K_a\) value will indicate that you are dealing with a very strong acid and that it will completely dissociate into ions. A small \(K_a\) will indicate that you are working with a weak acid and that it will only partially dissociate into ions. General Guide to Solving Problems involving \(K_a\) Generally, the problem usually gives an initial acid concentration and a \(K_a\) value. From there you are expected to know: • How to write the \(K_a\) formula • Set up in an ICE table based on the given information • Solve for the concentration value, x. • Use x to find the equilibrium concentration. • Use the concentration to find pH. How to write the \(K_a\) formula The general formula of an acid dissociating into ions is \[HA_\] This can be flipped to calculate pH from hydronium concentration: \[pH = -\log[H_3O^+]\] • An acidic solution is one that has an excess of \(H_3O^+\) ions compared to \(OH^-\) ions. • An basic (or alkaline) solution is one that has an excess of \(OH^-\) ions compared to \(H_3O^+\) ions. • A neutral solution is one that has equal concentrations of \(OH^-\) ions and \(H_3O^+\) ions. At 25 °C, we can correlate whether a solution is a...

\( \newcommand\) • • • • • • • • • • • • • • \(K_a\) is an acid dissociation constant, also known as the acid ionization constant. It describes the likelihood of the compounds and the ions to break apart from each other. As we already know, strong acids completely dissociate, whereas weak acids only partially dissociate. A big \(K_a\) value will indicate that you are dealing with a very strong acid and that it will completely dissociate into ions. A small \(K_a\) will indicate that you are working with a weak acid and that it will only partially dissociate into ions. General Guide to Solving Problems involving \(K_a\) Generally, the problem usually gives an initial acid concentration and a \(K_a\) value. From there you are expected to know: • How to write the \(K_a\) formula • Set up in an ICE table based on the given information • Solve for the concentration value, x. • Use x to find the equilibrium concentration. • Use the concentration to find pH. How to write the \(K_a\) formula The general formula of an acid dissociating into ions is \[HA_\] This can be flipped to calculate pH from hydronium concentration: \[pH = -\log[H_3O^+]\] • An acidic solution is one that has an excess of \(H_3O^+\) ions compared to \(OH^-\) ions. • An basic (or alkaline) solution is one that has an excess of \(OH^-\) ions compared to \(H_3O^+\) ions. • A neutral solution is one that has equal concentrations of \(OH^-\) ions and \(H_3O^+\) ions. At 25 °C, we can correlate whether a solution is a...

Main article: This timeline shows the whole years ago, that is, Each row corresponds to a change in log (time before present, that is, the logarithm of the time before the present) of about 0.1 (using base 10 logarithm). The dividing points are taken from the R′′20 The table is divided into sections with subtitles. Note that each such section contains about 68% of all the time from the beginning of the section until now. Past [ ] Visual timelines including ages The following five timelines show the geologic time scale to scale. The first shows the entire time from the formation of the Earth to the present, but this gives little space for the most recent eon. The second timeline shows an expanded view of the most recent eon. In a similar way, the most recent era is expanded in the third timeline, the most recent period is expanded in the fourth timeline, and the most recent epoch is expanded in the fifth timeline. Millions of Years (1st, 2nd, 3rd, and 4th) Thousands of years (5th) 13,800 million years ago to 5,500 million years ago [ ] Time interval, before the present time. a= Event, invention or historical development 13.8 11 Ga – 9 Ga Formation of the 9 Ga – 7 Ga Formation of the earliest 7 Ga – 5.5 Ga Formation of the exoplanets 5,500 million years ago to 1,800 million years ago [ ] Time interval, before the present time. a= Event, invention or historical development 5.5 Ga – 4.5 Ga Pre- The dark-energy dominated era starts after the 4.5 Ga – 3.5 Ga beginning of Formati...