what is radioactivity?

Answer 1

Radioactivity is the spontaneous emission of energy from unstable atoms.

Atoms are found in all natural matter. There are stable atoms, which remain the same forever, and unstable atoms, which break down or 'decay' into new atoms. These unstable atoms are said to be 'radioactive', because they emit radioactivity from the nucleus as they decay.

Radioactive elements, such as uranium, thorium and potassium break down (decay) fairly readily to form lighter atoms. The energy that is released in the process is made up of small, fast-moving particles and high-energy waves. These particles and waves are, of course, invisible. (The level of radioactivity of an element varies according to how stable its atoms are). Other elements with naturally occurring radioactive forms, (isotopes) are carbon, bismuth, radon, and strontium.

Radioactivity is a random process that happens naturally as the isotopes in particular elements decay. The isotopes continue to break down over time. The length of time that is taken for half of the nuclei in an element to decay is called its 'half-life'. A half-life can be very short (milliseconds to hours) or very long (hundreds of thousands of years).

Radiation also arises from nuclear fission. Fission can be spontaneous but is usually initiated in a nuclear reactor. Fission is a radioactive process; it releases energy as the heavy nucleus is split into two.

Radioisotopes are commonly used in medicine, and are produced as a by-product of nuclear energy.

Answer 2

Google: radioactivity

Answer 3

Radioactivity is an unstable atom's attentency to fall apart. Ions and other types of unstable atoms release energy as the fall apart in a process called radioactive decay. This releases radiation in the form of electromagnetic waves. In an atomic bomb, with Uranium, they split uranium atoms in a process called fission. This speeds the radioactive decay process from years to milliseconds. So all that radiation and energy is released which is why it melts, mutates, kills, and destroys everything in its path.

Answer 4

The propor defination is -
Heavy elements like uranium, thorium, radium etc. posses the property of spontaneously emitting highly penetrating and invisible rays (radiation). This property is called radioactivity. And Substances are called as radioactive substances.

Answer 5

Radioactivity is the process by which unstable elements become more stable by emitting particles and energy.

Answer 6

a guy who used an x-ray YEARS & YEARS in the past used to place his hand below the ray to concentration it, his hand grew to become black, and have been given burned just about to the bone, that grew to become into as quickly as we found out that radioactivity grew to become into risky.

Answer 7

radioactivites are rays emited from natural substance.
these rays can be harmfull and can be usefull( put in mind thatit can affect the human
genes)

Answer 8

I'll take a guess at Gamma radiation....