Chemistry Review 5.16.12
1. What is the definition of an atom?
Small part of an element.
2. What is an element?
A substance that cannot be broken down into smaller substances.
3. What is an atomic number?
The number of protons in that atom.
4. What is atomic mass?
The weight of an atom in the periodic table.
5. Where can the nucleus of an atom be found and what makes up the nucleus?
The nucleus is in the middle of the atom. Inside the nucleus are the protons and
6. Fill in the box below with the information found off of the periodic table for Beryllium. Label the atomic number, atomic mass, symbol, and element name.
7. What are the sub-atomic particles of an atom?
They are the neutrons, protons, electrons.
8. What charges do the sub-atomic particles have?
Positive, negative, and neutral.
9. What sub atomic particle always identifies the name of an element?
The protons.
10. What are the columns in the periodic table called and what do they show?
Groups or families. Show valence electrons.
11. What are the rows in the periodic table called and what do they show?
The rows are the periods. They show the number of occupied energy levels in the row
12. Using the periodic table, find the element that is found in group 2 period 3.
Magnesium.
13. What is an Ion?
A subatomic particle with a charge.
14. Draw a diagram of a sodium atom
They are the neutrons, protons, electrons.
8. What charges do the sub-atomic particles have?
Positive, negative, and neutral.
9. What sub atomic particle always identifies the name of an element?
The protons.
10. What are the columns in the periodic table called and what do they show?
Groups or families. Show valence electrons.
11. What are the rows in the periodic table called and what do they show?
The rows are the periods. They show the number of occupied energy levels in the row
12. Using the periodic table, find the element that is found in group 2 period 3.
Magnesium.
13. What is an Ion?
A subatomic particle with a charge.
14. Draw a diagram of a sodium atom
14A. How many valence electrons does sodium have?
12.
14B. How many neutrons does sodium have?
1.
14C. How many energy levels does sodium have?
3 levels.
14D. Is sodium stable?
No.
14E. Will sodium lose or gain electrons? What charge would sodium have?
It will lose electrons. The sodium would have a +1 charge.
15. If I have a charge of + 2 and I have 5 electrons, what element am I?
Nitrogen Ion.
16. If I have a charge of – 3 and I have 8 electrons what element am I?
Boron Ion.
17. How many elements and atoms do I have in Na2Cl3(O3H)3 ?
4 elements. 17 atoms.
18. How many elements and atoms do I have in 2NaCl2O3H ?
4 elements. 14 atoms.
19. Is carbon a metal or non-metal and list at least 3 properties of carbon?
Nonmetal.
20. Is sodium a metal or non-metal and list at least 3 properties of sodium?
It is a metal. It has one valence electron, it is highly reactive, made of metal.
21. List two Noble Gases and explain why they are unique.
Neon and Argon have full valence electron levels making them very stable.22. List two Alkali Metals and explain why they are unique. Lithium and sodium are themost reactive elements since they only have one valence electron in their outer energy level.23. What are the specific names of all the groups on periodic table starting with the alkali
metals?
Alkali metals, hydrogen group, alkaline earth metals, transition metals, boron group,carbon group, nitrogen group, oxygen group, halogens, noble gases, rare earth metals.24. What are Valence electrons?
The amount of leftover electrons an atom has.
25. How many electrons can the 1st, 2nd and 3rd energy levels hold?
1: 2, 2:8, 3:8.
26. Which group of elements has their valence electrons in their outer shell full?
The noble gasses.
27. How many valence electrons does Oxygen and Nitrogen have?
Oxygen, 6. Nitrogen, 5.
28. How can you find the number of valence electrons for an element?
You can find it bylooking at their group number or column number.
29. How can you find the number of energy levels needed for an element?
You can find it bylooking at the element’s period number or row number.
30. What is the most important sub-atomic particle when it comes to chemical reactions?
Its valence electrons.
31. What is a compound?
Two or more elements chemically combined have their own uniquebproperties.
32. Give an example of a compound.
H2O33. What is a molecule?
An element with more than one atom attached to it
34. Give an example of a molecule.
O₂- air we breathe O₃- ozone layer.
35. As you go from left to right on the periodic table, describe the changes that occur to element's atomic structure.
Its mass increases because it has more protons, neutrons and electrons.
36. What is a chemical reaction?
Formed from a chemical change when 2 or more substances react to make a new substance with its own unique properties.37. What are indicators that a chemical reaction took place?
A new substance with its own unique properties is formed. Good evidence is when a new gas is formed; heat or light is produced; a precipitate is formed; rusting/tarnishing.
38. Was the zinc and hydrochloric acid combination a chemical reaction? What were someindicators?
Yes because a new gas was formed.
39. If I combined sodium and water together, would there be a chemical reaction? How do you know?
Yes because a new substance would be formed and heat/energy would alsobe present.
40. Balance the following chemical equations.
CH4 + O2N2 + 3H22HCl + Ca(OH)2CO2 + 2H2O not balanced2NH3 not balanced
CaCl2 + 2H2O not balanced 2S + 3O22SO3 not balanced.
41. What were some indicators that a chemical reaction took place in the calcium chloride baggy lab? Explain.
Gas formation, color change, temperature increase.
42. What does the Law of Conservation of Mass state?
Mass/matter cannot be created nor destroyed.
43. How did the balloon, baking soda, and vinegar lab prove the Law of conservation of Mass?
The mass was the same before and after the chemical reaction took place.
44. Do these chemical reactions follow the Law of Conservation of Mass explain your answer?
Formula:Na2 + O → NaO no it’s not balanced
H2 + O → H2O yes it’s balanced
45. Describe how the properties of metals, non-metals, and metalloids differ.
Metals are good conductors of heat and electricity; they’re malleable, ductile, lustrous,mostly silver in color.Nonmetals are poor conductors of heat and electricity; they’re brittle and dull in color. Metalloids are semiconductors of heat and electricity and only somewhat malleable and ductile