Worksheet 3 Crossword

3. a mathematical model that shows where an electron is likely to be, but not exactly, due to the electron's particle-wave duality.
5. a chemical composed of two or more elements.
7. fundamental particles with little mass and -1 charge and are found orbiting the nucleus of atoms.
9. different forms of the same element with different numbers of neutrons.
12. is zero, because an atom by definition has an equal number of protons and electrons.
14. a measure of the pull an atom of an element exerts on shared electrons in a chemical bond.
16. hydrogen-2, an isotope of hydrogen with one neutron in its nucleus.
17. the minimum energy needed to remove a single electron from an atom or molecule. X(g) + energy ⟶ X+(g) + e−
18. a pure substance distinguished by a unique atomic number.
19. an ion with a negative charge.
20. the sum of its number of protons and its number of neutrons.

1. composed of two down quarks and an up quark, have neutral charge, and can be found in the nucleus of atoms.
2. a row of elements on the periodic table, with each element having the same number of electron shells.
4. an arrangement of the elements by atomic number and structure first proposed by Dmitri Mendeleev.
6. used to find an ion's mass-to-charge ratio using a beam of electrons.
8. an ion with a positive charge.
10. a column of elements on the periodic table, with each element having the same number of valence electrons.
11. at the center and holds the most mass, consisting of protons and usually neutrons.
13. a measure of the size of its atoms, usually the average distance from the center of the nucleus to the boundary of its electron shells. r=0.53 × (n^2/Z) Å
15. particles made up of two up quarks and one down quark, have +1 charge, and can be found in the nucleus of atoms.