Chemistry

5. Atoms cannot be __________, created, or destroyed.
8. A ________ formula indicates the relative numbers of atoms of each kind in a chemical compound by using atomic symbols and numerical subscripts.
9. is a unique element.
12. The second row of the f block are known as?
13. has just three valence electrons, which tends to form bonds in which it is surrounded by six electrons.
14. The elements of Group 2 of the periodic table are called the alkaline-_____ metals.
16. Red Atoms of different elements combine are known as?
18. electron of one atom and proton of the other atom _______ one another.
19. A molecular formula shows the types and numbers of atoms combined in a single molecule of a molecular compound.
21. two nuclei and two electrons _____ each other.
22. A ________ is a neutral group of atoms that are held together by covalent bonds.
23. A chemical compound whose simplest units are molecules is called a _________ compound.
25. is an arrangement of the elements in order of their atomic numbers so that elements with similar properties fall in the same column, or group.
26. a chemical compound containing elements in exactly the same proportions by mass regardless of the size or source of the compound.
27. All matter is composed of extremely small particles called?

1. The first row of the f block are known as?
2. In the periodic table, the f-block elements are wedged between Groups 3 and 4 in the sixth and ______ periods.
3. Repeating patterns are referred to as ________.
4. the p block includes all of the nonmetals except hydrogen and ______.
6. is the energy required to break a chemical bond and form neutral isolated atoms.
7. ______ is used to form chemical compounds.
10. states that the physical and chemical properties of the elements are periodic functions of their atomic numbers.
11. if two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers.
14. The energy change that occurs when an electron is acquired by a neutral atom is called the atom’s electron affinity.
15. is a measure of the ability of an atom in a chemical compound to attract electrons from another atom in the compound.
17. Cationic and _______ radii decrease across a period.
20. The elements of Group 1 of the periodic table are known as the _____ metals.
22. The p-block elements together with the s-block elements are called the __________ elements.
23. All six of the __________ are also in the p block.
24. the attraction between two or more atoms that allows them to be able to form a stable chemical compound.