Final Exam Review: Chemistry

Name ______

Final Review Answer Key

Chapter 3: Properties of Matter

1. What is the difference between mass and weight? Mass is the amount of matter in an object. Weight is based upon the gravitational pull upon the mass. Will your mass change or will your weight change if you go to the moon? Only weight will change. 2. Name a fluid with high viscosity. Motor oil Name a fluid with low viscosity. water Is viscosity a physical or chemical property? Physical 3. What is the formula for density? Density = mass/volume Is density a physical property or chemical property? physical 4. Draw the magic circle for density.

5. What is the mass of a brick that has a density of 4.2 g/cm3 and a volume of 300 cubic centimeters? 12.6 g 6. What is the volume of a liquid that has a mass of 12 grams and a volume of 15 ml? .8 g/ml If poured into water, will that liquid float or sink? float

7. Name two physical properties of water. Freezes at 0 ⁰ C, boils at 100 ⁰ C

8. Identify these as physical changes (P) or chemical changes (C): burning C freezing P grinding P boiling P

9. What’s the difference between a compound and a mixture? Mixtures can be separated fairly easily, compounds cannot be separated easily.

Chapter 4: Atoms

Fill in this table:

Sub-atomic particle Charge Mass (in amu) Location in the atom Proton + 1 amu Nucleus Neutron None 1 amu Nucleus Electron -- none Electron cloud 1. How are isotopes alike, and how are they different? Have same number of protons, different number of neutrons. 2. What does the atomic number tell you about an atom? Number of protons (number of electrons, if it is of an element) 3. What does the mass number tell you? Number of protons and neutrons 4. Describe Dalton’s atomic theory.1. all matter composed of atoms, 2. All atoms of a given element are identical, 3. Atoms cannot be created or destroyed, 4. Atoms combine in whole number ratios to form compounds, 5. In chemical reaction atoms are separated, combined or rearranged.

5. How many protons, neutrons, and electrons are in: Iron-56 p+ = 26, n⁰ = 30, e— = 26 Calcium-41 p+ = 20, n⁰ = 21, e— = 20 Name ______

64 + — 29 Cu p = 29, n⁰ = 35, e = 29 6. What is the mass of the most common isotope of sodium? 23 lithium? 7 7. What part of the atom has virtually all the mass? nucleus 8. What part of the atom has virtually all the volume? Electron cloud 9. What element has 15 protons in its nucleus? phosphorus 10. What is the mass number of an atom that has 5 protons, 6 neutrons, 5 electrons? 11 amu

Chapter 5: Electrons in Atoms

1. Draw Bohr models for these atoms: lithium Sodium Neon Helium

2. What is correct about the Bohr model, and what is incorrect? It places the protons and neutrons in the nucleus, and electrons orbiting it (where all belong). It incorrectly has the electrons orbiting in fixed orbitals (they are actually in a cloud) 3. How many electrons can fit in – the first energy level? 2 the second energy level? 8 the third energy level? 8

4. How many valence electrons are in titanium. 2 5. Write noble-gas configurations for the following elements: a. cesium Xe b. bromine Kr 6. What does an electron have to do to move to an energy level farther from the nucleus? Become excited (take on energy)

Chapter 6: The Periodic Table 1. What group number corresponds to these group names? Alkaline earth metals 2 Halogens 17 Transition metals 3 - 12 Noble gases 18 2. How many valence electrons do the elements in these groups have? Group 1 1 Group 2 2 Group 13 3 Group 16 6

3. Add the correct charge to each of these ions: Sr Na Al Ag F S O Li Zn +2 +1 +3 +1 -- 1 -- 2 -- 2 + 1 + 2 Name ______

4. Which atoms are the smallest? H Which atoms are the largest? Fr

5. Which element is the most electronegative? F Which is the least? Fr 6. What is electronegativity, anyway? Ability to attract electrons

7. Why don’t the noble gases form ions? They have full valence electrons

8. As you move down a group in the Periodic Table, do the atoms get smaller or larger? larger Why? Number of protons and neutrons increases and electrons are further away from the nucleus 9. Which group of metals is most reactive? Alkali metals Which group of non-metals is most reactive? halogens

Chapter 8: Ionic Compounds

1. Indicate the charge of the ion each element would form, and then use the criss-cross rule to find the formula for each of these compounds:

+1 -2 +2 —1 Lithium oxide Li O Li2O Calcium iodide Ca I CaI2

+2 -1 +3 —2 Iron (II) nitrate Fe NO3 Fe(NO3)2 Aluminum sulfide Al S Al2S3

+1 –3 +2 -3 Ammonium nitride NH4 N (NH4)3N Strontium phosphate Sr PO4 Sr3(PO4)2

+1 —2 +1 --2 Sodium carbonate Na CO3 Na2CO3 Silver oxide Ag O Ag2O

+4 –2 +1 -2 Lead (IV) oxide Pb O PbO2 Copper (I) sulfate Cu SO4 Cu2SO4 2. Why do atoms form compounds? Trying to get full valence electrons 3. How does an atom form a cation? Give off electrons to get full valence electrons 4. How does an atom form an anion? Take on electrons to get full valence electrons 5. Name these compounds: Fe2O3 Iron III oxide CaSO4 calcium sulfate AgNO3 Silver nitrate K2S potassium sulfide

6. How many protons and electrons are in Cl_? P+ 17 e—18 in Be2+? P+ 4 e—2 7. Ionic bonds form between what type of elements? Metal and a non-metal

Chapter 9: Covalent Compounds

1. What’s the difference between an ionic compound and a covalent compound? Ionic compounds formed from a metal and a nonmetal which give up or take on electrons causing them to be attracted to each other. Covalent compounds are formed by two non metals sharing electrons. 2. What is a molecule? 2 or more atoms combined together to act as 1 single unit.

3. Identify these formulas as compounds, molecules, both, or neither: AgCl molecule N2O3 compound I2 molecule AlN molecule CO molecule NiCO3 molecule Name ______

4. List the seven elements that exist as diatomic molecules when they’re in the pure state. Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine 5. Draw the Lewis structure for:

3- N2 Phosphate ion, PO4 .. :N≡N: :O: .. | .. : O – P – O : .. | .. :O: .. NH3 CO2 .. .. H – N – H :O = C= O: | H

6. Name the following compounds: a. CO carbon monoxide b. CCl4 carbon tetrachloride c. P2O3 diphosphorus trioxide d. N2O5 dinitrogen pentaoxide

7. When naming a compound, what do you look for to decide if it’s an ionic compound or a covalent compound? Look at the first element if metal = ionic, if nonmetal = covalent

8. Name these compounds: a. KCl potassium chloride b. SO3 sulfur trioxide c. SiF4 silicon tetrafluoride d. Fe(NO3)3 Iron III nitrate e. AgF silver fluoride f. BiBr2 bismuth bromide

9. Covalent bonds from between what types of elements? Non-metal – non-metal

Chapter 10: Chemical Reactions

1. In a chemical formula atoms containing more than one of a particular element are designated by using subscripts .

2. In a chemical equation, you balance the total number of each element on each side of the equation by using coefficients 3. Chemical equations can be divided into two parts: reactants, (what you start with at the beginning of the reaction), and products (what you end up with after the reaction). 4. During a chemical reaction atoms are: rearranged. 5. The five (5) types of chemical reactions are: synthesis, decomposition, single replacement, double replacement, combustion.

1 2 3 4 5 6 7 8 Valence +1 +2 +3 +4/-4 -3 -2 -1 0 ionic charge c charge Name ______

2 8 8 8 8 8 8 s l

a s t l e a t m e

h s m s t l

e r s a

t s a n s e e d s o

a i i n e m t g o

i e l n i l s e i l g l l a n a o t a b l a k e o k a l r l n A a T M H

What is similar about elements in the same column on the periodic table? Same number valence electrons, share similar properties

Define the term viscosity and give two examples. Resistance of a liquid to flow. Thicker the liquid, slower it flows.

State the law of conservation of mass: Mass cannot be created or destroyed in a chemical reaction.

Describe how to properly read the meniscus formed in a graduated cylinder. Read the bottom of the curve of the liquid. Estimate the final number. Name ______

Equipment identification 25 20 15 30 30 10 5 20 20 10 10 1 2 3 Graduated cylinder Flask Beaker

Properties:

Sample/ Luster Conductivity Malleability Reaction Question w/acid Non Metal Sample A Dull None Brittle None

Metal Sample B Shiny Medium Malleable Yes Sample C Shiny Medium Brittle No Metalloid