Answer:
84
Explanation:
42 X 2 since it is a pair
Plankton is part of an aquatic ecosystem
Answer:
Figure 3
Explanation:
A mixture is a substance made up of two or more different kind of atoms arranged in such a way that they are not chemically linked or joined. This accounts for the reason a mixture can be separated easily. In the figures attached as an image in this question:
- Figure 1 represents an element because it is made up of only hydrogen atoms chemically bonded together to form a molecule.
- Figure 2 represents a compound because it contains hydrogen and carbon atoms chemically joined together.
- Figure 3 represents a MIXTURE because it contains the oxygen and carbon atoms, which are not chemically joined to one another. As seen in the image, the oxygen atoms are not joined to the carbon atoms.
- Figure 4 represents a compound because it contains oxygen and hydrogen atoms chemically bonded together.
Answer:
Nuclear decay rates are constant
Explanation:
Spontaneous decay of unstable nuclei is a process of a statistical nature, it is not possible to predict with certainty when an individual radioactive nucleus will decay, nor can the decay process be influenced in any way.
Therefore, the half-life of radionuclides (specific for each radionuclide) is defined as the time period in which half of the initial number of radioactive nuclei decays.
The unit of measurement for the radioactivity of the material is the becquerel (Bq) and denotes the number of decays in one second (1Bq = 1 decay / 1 second).
