Radioactivity or radioactive decay is the process that occurs when unstable isotopes or atoms release energy by emitting radiations such as ,gamma radiations, alpha radiations and beta radiations to attain stability. Therefore, in this case decay is likely to occur when a given atom has two many neutrons in its nucleus in order to attain stability.
Answer:
Ordinary table salt is called sodium chloride. It is considered a substance because it has a uniform and definite composition. All samples of sodium chloride are chemically identical. Water is also a pure substance. Salt easily dissolves in water, but salt water cannot be classified as a substance because its composition can vary. You may dissolve a small amount of salt or a large amount into a given amount of water. A mixture is a physical blend of two or more components, each of which retains its own identity and properties in the mixture . Only the form of the salt is changed when it is dissolved into water. It retains its composition and properties.
Homogeneous Mixtures
A homogeneous mixture is a mixture in which the composition is uniform throughout the mixture. The salt water described above is homogeneous because the dissolved salt is evenly distributed throughout the entire salt water sample. Often it is easy to confuse a homogeneous mixture with a pure substance because they are both uniform. The difference is that the composition of the substance is always the same. The amount of salt in the salt water can vary from one sample to another. All solutions would be considered homogeneous because the dissolved material is present in the same amount throughout the solution.
One characteristic of mixtures is that they can be separated into their components. Since each part of the mixture has not reacted with another part of the mixture, the identities of the different materials is unchanged.
Answer:
m
Explanation:
C = Fλ
C: Speed of light = 
m/s
f: Frequency (Hz)
λ: Wavelength (m)
Rearrange formula for wavelength:
C/F = λ
Answer:
hope you like it
Explanation:
because ouytermost shell contains two electrons
calcium is in group 2 so its valency is two valency is the number of outer shelll electrons it needs to have an stable outer shell . it needs 2 more .
Answer:
the protein capsid of naked viruses is less susceptible to environmental . condition
Explanation:
because the envelop is made in part of phospholipids. once the envelop is lysed ,the virus loses its functiovnal receptors and still able to infect susceptible cells.
