Atomic Structure
A(n) __________________________ uses the symbol of the element and dots to represent the electrons in the outer energy level.
3. electron dot diagram
A __________________________ is a type of matter with a fixed composition.
2. pure substance
All substances are built from atoms. If all the atoms in a substance have the same identity, then that substance is a(n) _________________________.
14. element
Rutherford discovered the nucleus of an atom by doing the _________________________ experiment.
13. gold foil
__________________________ is a chemical reaction between silver metal and sulfur compounds in the air that results in sulfide.
17. tarnish
Because elements in the same group have the same number of _______________________ in their outer level, they will undergo chemical reactions in similar ways.
5. electrons
When a substance freezes, boils, evaporates, or condenses, it undergoes a______________________ .
12. physical change
____________________ and ________________________ are radioactive isotopes that archaeologists use most often to date once-living organisms.
25. carbon-13, carbon-14
Which scientist came up with the concept of an electron cloud as well as our current model of the atom?______
19. Schrodinger
It is the number of electrons in the outer energy level that determines the _____________________________ of an atom.
24. chemical properties
The outer electrons are called _____________________ electrons.
8. valence
Any characteristic of a material that you can observe without changing that you can observe without changing the identity of the substances that make up the material is a(n) _____________________
4. physical properties
Solid calcium carbonate, a compound that mostly makes up________________________, does not dissolve easily in water.
31. limestone
Scientist have found that electrons within the electron cloud have different amounts of_____
34. energy
The tendency of a substance to burn, or its flammability, is an example of a______
26. chemical property
The maximum amount of electrons that can be in the outer level of electrons is ___________________________.
1. 8 electrons
Atoms of the same element that have different numbers of neutrons are called _______
20. isotopes
The mass of a proton is equal to ____________________.
41. 1 amu
What scientist first came up with the concept of an atom? (Billiard ball model)
35. Dalton
The unit used for atomic particles is the______________________________, or amu.
37. atomic mass unit
You use the name of the element followed by the __________________________ of the isotope to identify each isotope.
9. mass number
When you burn wood (or anything ) a _____________________ takes place.
43. chemical change
Many scientist believe believe that ________________ and ___________________ are the building blocks of other elements.
6. hydrogen, helium
Numbers of neutrons = ________________number - ______________ number
36. mass, atomic
The ORIGINAL periodic table arranged elements in order of increasing _______________________ and he discovered a pattern.
42. atomic mass