Answer:
a new scientific discovery that benefits the environment
The number of protons uniquely identifies the element. This is not on the periodic table. Isotopic notationincludes the atomic number and the mass number. 8 17 This isotope of oxygen has 8 protons (atomic number), 8 electrons and 9 neutrons
Answer:
Yes.A compound is a molecule made of atoms from different elements. All compounds are molecules, but not all molecules are compounds. Hydrogen gas (H2) is a molecule, but not a compound because it is made of only one element.
Answer:
As
Explanation:
For any element to exhibit the pattern of ionization energy shown in the question, it must possess five electrons in its outermost shell. These five electrons are not lost at once. They are lost progressively until the valence shell becomes empty. The ionization energy increases steadily as more electrons are lost from the valence shell.
The only pentavalent element among the options in arsenic, hence the answer.