What is the half-life of Caesium 137?

30 years
Cesium-137 is significant because of its prevalence, relatively long half life (30 years), and its potential effects on human health. Cesium-137 emits beta particles as it decays to the barium isotope, Ba-137m (half life = 2.6 minutes).

How do you calculate the half-life of cesium-137?

놀를 = Page 2 [2] (5 points total) The half-life of cesium-137 is 30 years. Suppose we have 100-mg sample. a) (2.5 points) Find a formula for the mass remaining after t years. Plt) = cekt p(30)=50 by half-life c=100.

What is the half-life of metastable barium 137?

The parent isotope Cs-137 with a half-life of 30.1 years beta decays (94.6%) to the metastable state of Ba-137m. This further decays by gamma emission (662 keV) with a half-life of 2.6 min. to the stable Ba-137 element.

What is the decay constant of cesium-137?

Cs decays with a half-life of (30.05 ± 0.08) years [4] to either the 137Ba ground state, with emission of a β particle (Q = 1176 keV, 5.3%), or to 137mBa (Q = 514 keV, 94.7%) which rapidly (t1/2 = 2.552 min) decays to the 137Ba ground state with emission of a 661.7 keV γ photon.

Why is SR 90 hazardous?

Sr-90 can be inhaled, but ingestion in food and water is the greatest health concern. Once in the body, Sr-90 acts like calcium and is readily incorporated into bones and teeth, where it can cause cancers of the bone, bone marrow, and soft tissues around the bone.

What does cesium-137 do to the human body?

External exposure to large amounts of Cs-137 can cause burns, acute radiation sickness, and even death. Exposure to Cs-137 can increase the risk for cancer because of exposure to high-energy gamma radiation.

How long does it take for 50% of the BA 137 BA 137 to decay?

Ba-137m has a half-life of only 2.55 minutes (153 seconds) and quickly decays down to its stable ground state by the emission of a 0.662 MeV gamma ray.

What type of radiation is Cs-137?

gamma rays
A Cs-137 atom emits radiation in the form of medium energy gamma rays, and to a lesser extent, high-energy beta particles, which disrupt molecules in cells and deposits energy in tissues, causing damage.

Why is cesium 137 used?

Cesium Sources Cesium-137 is used in small amounts for calibration of radiation detection equipment, such as Geiger-Mueller counters. In larger amounts, Cs-137 is used in: Medical radiation therapy devices for treating cancer. Industrial gauges that detect the flow of liquid through pipes.

Do we all have strontium-90?

Naturally occurring strontium is nonradioactive and nontoxic at levels normally found in the environment, but 90Sr is a radiation hazard….Radioactivity.