Beta Decay of Potassium-40

40K → 40Ca + e− + ν̄e

개요

Potassium-40 decays to calcium-40 by beta emission (89.3%) or to argon-40 by electron capture (10.7%). With a half-life of 1.25 billion years, K-40 is the largest source of natural radioactivity in the human body. K-Ar dating is used for rocks millions to billions of years old.

참여 물질

역할 물질 계수 상태
반응물 Potassium K 1 (s)
생성물 Calcium Ca 1 (s)

일상 속 예시

Every human body contains about 4,400 Bq of K-40 radioactivity from potassium in food, primarily from bananas, potatoes, and meat.

산업적 중요성

K-Ar 및 Ar-Ar 연대 측정은 화산암 연대를 측정하고 지질학적 시간 척도를 설정하는 데 사용됩니다. K-40은 또한 방사선 감지의 배경 방사선원이기도 합니다.

성질

유형
Nuclear
가역 반응
아니오
에너지
발열
ΔH
-130000000.0 kJ/mol

관련 반응

Alpha Decay of Radium-226 Alpha Decay of Radon-222 Alpha Decay of Thorium-232 Neutron Capture by Uranium-238 Beta Decay of Iodine-131 Beta Decay of Strontium-90 Alpha Decay of Polonium-210 Americium-241 Alpha Decay Beta Decay of Cobalt-60 Electron Capture by Beryllium-7

Frequently Asked Questions

What is the equation for Beta Decay of Potassium-40?
The balanced equation is: ⁴⁰K → ⁴⁰Ca + e⁻ + ν̄ₑ.
What type of reaction is Beta Decay of Potassium-40?
Beta Decay of Potassium-40 is a nuclear reaction.
Is Beta Decay of Potassium-40 exothermic or endothermic?
Beta Decay of Potassium-40 is exothermic (releases energy). The enthalpy change (ΔH) is -130000000.0 kJ/mol.