Katal
The katal (symbol kat) is a unit derived from the International System of Units to measure catalytic activity, especially in the fields of medicine and biochemistry. It is defined as the catalytic activity responsible for the transformation of one mole of compound per second.
The name katal has been in use for 30 years, but only became official during the 21st General Conference on Weights and Measures in 1999.
In enzyme kinetics, it is the amount of enzyme needed to transform one mole of substrate per second. 1 katal equals 60 x 106 units of enzyme activity. As it is a very large unit, its microkatal (μkat) and nanokatal (nkat) submultiples are usually used.
Definition
A katal refers to an enzyme catalyzing the reaction of one mole of substance per second. Since this is a large unit for many enzymatic reactions, the nanokatal (nkat) is used in practice.
kat=mols{displaystyle {text{kat}}={frac {text{mol}}{text{s}}}}{text{s}}}}}
The katal is not used to express the reason for a reaction; which is expressed in units of concentration per second, such as moles per liter per second. Rather, the katal is used to express catalytic activity, which is a property of catalysis.
IF multiples
| Submultiplos | Multiple | ||||
|---|---|---|---|---|---|
| Value | Symbol SI | Name | Value | Symbol SI | Name |
| 10−1 kat | dkat | decikatal | 101 kat | dakat | decakatal |
| 10−2 kat | ckat | centikatal | 102 kat | hkat | hectokatal |
| 10−3 kat | mkat | millikatal | 103 kat | kkat | kilokatal |
| 10−6 kat | μkat | microkatal | 106 kat | Mkat | megakatal |
| 10−9 kat | nkat | nanokatal | 109 kat | Gkat | gigakatal |
| 10−12 kat | pkat | picokatal | 1012 kat | Tkat | terakatal |
| 10−15 kat | fkat | femtokatal | 1015 kat | Pkat | petakatal |
| 10−18 kat | akat | attokatal | 1018 kat | Ekat | exakatal |
| 10−21 kat | zkat | zeptokatal | 1021 kat | Zkat | zettakatal |
| 10−24 kat | ykat | yoctokatal | 1024 kat | Ykat | yottakatal |
History
The General Conference on Weights and Measures and other international organizations recommend the use of the katal. I replace the non-SI enzyme unit of catalytic activity. The enzyme unit is even more commonly used than the katal, especially in biochemistry. The adoption of the katal has been slow.
Origin
The name "katal" It has been used for decades. The first proposal to make it an SI unit came in 1978, and it became an official SI unit in 1999. The name comes from the ancient Greek κατάλυσις (katalysis), meaning "dissolution".;, the word "catalysis" itself is a Latinized form of the Greek word.