Answer:
C. Fluorine because the model has 9 protons which is represented by the atomic number
Explanation:
We usually identify an element by the number of protons in them. The number of protons is the atomic number of an atom.
- Every atom has a specific number of protons in them.
- This number of protons is the atomic number.
- According to the periodic law, atoms are arranged on the periodic table based on their atomic number.
- The given fluorine atom has 9 protons which represents the atomic number of the atom.
- This way, the given number clearly shows the right model for identifying the chemical specie.
Chemists have developed insulation.
<h2>Answer : Option B) The hematite particles rearrange to form a new substance.</h2><h3>Explanation :</h3>
Hematite particles when gets rearranged to form a new substance, is an example of a chemical change.
As a chemical changes is usually a change where a substance undergoes a chemical change and forms a new substance; which cannot be easily reversed into reactants by any simple physical methods.
In this example the hematite ore forms a new substance by an irreversible chemical change.
Answer:
3)alpha decay because alpha particles have two protons and two neutrons
Explanation:
When a radioactive isotope undergoes a decay, a daughter nucleus or nuclei is/are formed. The mass number and atomic number of the daughter nucleus gives us an idea of the nature of radioactive decay that the parent nucleus underwent.
If the daughter mass number of the daughter nucleus is four units less than that of the parent nucleus and the atomic number of the daughter nucleus is two units less than that of the parent, then such a decay is an alpha decay.
An alpha particle has two protons and two neutrons thus it has a mass number of 4 and an atomic number of two.
