isotopes by aida syafinaz and nadiah chen

8/3/2019 Isotopes by Aida Syafinaz and Nadiah Chen

http://slidepdf.com/reader/full/isotopes-by-aida-syafinaz-and-nadiah-chen 1/18

Nadiah Chen Muhd IMran Chen

&

Aida Syafinaz Zainuddin

4Arif 2



Isotopes are atoms of the same element with the same

number of protons but different number of neutrons. In

nature, many elements exist as several isotopes. Theisotopes of hydrogen have special names, but the isotopes

of most elements do not have distinct names. For example,

the natural isotopes of carbon are 12C, 13C, and 14C

(carbon-12, carbon-13, and carbon-14). Most carbon atoms

are 12C, about 1.1 percent are 13C, and a tiny fraction are14C. An element’s atomic mass, or atomic weight, is theaverage of the mass numbers of a representative sample of

atoms of the element, with all isotopes in their normally

occurring proportions.



Hydrogen atom isotopes have different numbers of

neutrons The isotopes of hydrogen all have one protonin the nucleus, defining them as that element .Their

different mass numbers are due to different numbers

of neutrons.



• Some isotopes, called radioisotopes, are unstable and spontaneouslygive off energy as α (alpha), β (beta), or γ (gamma) radiation fromthe atomic nucleus.

• Biologists and physicians can incorporate radioisotopes into moleculesand use the emitted radiation as a tag to locate those molecules orto identify changes that the molecules undergo inside the body.

• Three radioisotopes commonly used in this way are 3H (tritium),14C(carbon-14), and 32P (phosphorus-32). In addition to theseapplications, radioisotopes can be used to date fossils

• Radioisotopes are useful for experiments and in medicine, even lowdoses of their radiation have the potential to damage molecules andcells.

• The devastating effects of radiation from nuclear weapons are wellknown, as are concerns about possible damage to organisms fromisotopes used in nuclear power plants.

• In medicine, γ-radiation from 60Co (cobalt-60) is used to damage orkill cancer cells.



• NUMBER OF PROTONS

• NUMBER OF ELECTRONS

• ELECTRON ARRANGEMENT• CHEMICAL PROPERTIES

SAME DIFFERENT• NUMBER OF NUCLEON

• NUMBER OF NEUTRON

• PHYSICAL PROPERTIES SUCH

AS DENSITY,MELTINGPOINT,BOILING POINT.



Radio isotopes are used to cause mutation in insects so as to make themsterile or to cause death. These serve as pest control in agriculture.

The metabolism of phosphorus by plants can be studied using phosphatefertilizers that contain phosphorus-32.

A small amount of phosphorus-32 is used in fertilizers.

The radiation produced by phosphorus-32decaying is detected by a

Geiger- Miller counter.

This method can trace the passage of phosphate ions in plants..

Carbon-14 is used to study the passage of carbon duringphotosynthesis in plants.



• There are two types of isotopes, namely

the stable isotopes (non-radioactive)

the non-stable isotopes (radioactive)

• Unstable isotopes go through radioactive decay and emit

• Radiation and they are known as radioisotopes.

• Radioisotopes have many applications in daily life.• Several uses of radioisotopes in daily life are shown in below



Isotope sodium-24 is used to detect leakage of underground pipes.

Beta rays are used to control the thickness of plastic, paper and metal

sheets in factory.

Gamma rays are used to detect whether cans or bottles are filled up to

the required amount.

Sodium-24 is used to measure the wear out rate of engine in a vehicle



Gamma rays of cobalt-60 are used to kill cancer cells without surgery inpatients. This treatment is known as radiotherapy

Patients with skin cancer can be treated using beta rays fromthe isotopes phosphorus-32 and strontium-90

Medical instruments such as surgical equipment, syringes and bandagescan sterilize by using gamma rays.

Radioisotopes are also used as tracers. A small amount of sodium-24 isinjected into the patient's body. A radioactive detector is then used todetect accumulation of sodium-24 and therefore detect tumors andblood clots before they become dangerous.

This tracing method is also used to investigate the thyroid glands bymeasuring the uptake of iodine-131.

Plutonium-238 in a nuclear battery is used to produce small electric

shocks in the heart pacemaker. People with irregular heartbeats need to have a heart pacemaker

implanted inside their chest. The nuclear battery of the pacemakerprovides a tiny electrical shock to ensure a steady heartbeat



The device images the patient's

body and detects

concentrations of the

radioisotope around the body.

Certain telltale signs or quirks

that the radioisotope do in thebody may give a diagnosis to

doctors



The accumulation of the Tc-

99m radioisotope tracer shows

a 'hot spot' indicating a cancer

in the cheek bone (maxillary

osteosarcoma) of this 17-year

old girl.



Smoke Detectors and Americium-241



Food irradiation is a method of treating food in order to make it safer to eat andhave a longer shelf life.

This process is not very different from other treatments such as pesticideapplication, canning, freezing and drying.

The end result is that the growth of disease-causing microorganisms or those thatcause spoilage are slowed or are eliminated altogether.

This makes food safer and also keeps it fresh longer. Food irradiated by exposing it to the gamma rays of a radioisotope -- one that is

widely used is cobalt-60. The energy from the gamma ray passing through the food is enough to destroy

many disease-causing bacteria as well as those that cause food to spoil, but is notstrong enough to change the quality, flavor or texture of the food. It is important tokeep in mind that the food never comes in contact with the radioisotope and isnever at risk of becoming radioactive.



Radioisotope carbon-14 is used to study and estimate the age of ancient

artifacts. This method is named as the radiocarbon dating.

Recalling that all biologic organisms contain a given concentration of

carbon-14, we can use this information to help solve questions about

when the organism died.

It works like this, when the organism died it has specific ratio by mass of carbon-14 to carbon-12 (the same ratio as the atmosphere) At the

moment of death, no new carbon containing molecules are metabolized,

therefore the ratio is at maximum.



Plutonium is used in nuclear reactor to produce electrical energy.

isotopes by aida syafinaz and nadiah chen

Documents