According to the report of US Environmental Protection
Agency, majority of large dose radiation exposure comes from natural background
radiation sources particularly the radioactive gases radon and thoron. This two
gases form when naturally occurring elements decay. However in the case of
man-made sources, the largest dose comes from medical x-rays.
Answer:
The dispersed particles are spread evenly throughout the dispersion medium, which can be a solid, liquid, or gas. Because the dispersed particles of a colloid are not as large as those of a suspension, they do not settle out upon standing.
Explanation:
The most abundant is 35/17 Cl
explanation
This is because Chlorine 35/17 is the one close to the average atomic mass of chlorine which is 35.46 u making it to be the most abundant.
average atomic mass of chlorine is 35.46 + or- 0.02
Double replacement means a reaction that includes two molecules that each have two different ions. After the reaction, the ions pairs have switched, which is what is shown in the above equation.
A single replacement would be a very simple reactions such as:
2Fe(II)S + Ov2^2- -> 2Fe(II)O + 2S^2-
A decomposition reaction would be shown as this:
2NaCl -(dissolve in water)> 2Na^+ + Clv2^-
A synthesis reaction could be the exact opposite:
2Na^1+ + Clv2^1- -> 2NaCl