Name___________________________________
Unit 2: Earth Chemistry Review
Multiple Choice
______ 1. How do the electrons in atoms form chemical bonds?
a. They are either shared or transferred between atoms
b. They are shared but not transferred between atoms
c. They are neither shared nor transferred between atoms
______ 2. When Elements and compounds combine to form new compounds, the reaction is
described in a…
a. Chemical mixture
b. Chemical equation
c. Gravity field
______ 3. Physical properties of matter are characteristics that
a. Can be observed without changing the composition of substances
b. Describe reactions between substances
c. Describe reactions between unreactive substances
______ 4. Where are electrons found in atoms?
a. In the electron sphere
b. In the atomic ring cycle
c. In the electron cloud
______ 5. In the chemical formula, CO2, what does the small 2 mean?
a. Two carbon atoms
b. Two carbon dioxide molecules
c. Two oxygen atoms
______ 6. How do compounds differ from mixtures
a. Compounds are made of chemically bonded substances and mixtures of
made of substances that are NOT bonded chemically
b. Mixtures are made of chemically bonded substances and compounds are
made of substances that are NOT chemically bonded
______ 7. Elements are arranged on the periodic table
a. In the order of the alphabet
b. In order of the atomic number
c. Randomly
______ 8. What are counted in an atom to determine its mass number?
a. Electrons and neutrons
b. Neutrons and protons
c. Protons and electrons
______ 9. Two types of chemical bonds are:
a. Positive and negative
b. ionic and covalent
c. atomic and covalent
_____10. How many atoms of sodium (Na) are there in the formula for table salt NaCl?
a. 2
b. 3
c. 1
______11. The attractive force between oppositely charged ions that result from the transfer
of electrons from one atom to another is known as:
a. Ionic bond
b. Covalent bond
c. Physical bond
______12. How many hydrogen atoms are in the chemical formula C6H12O6?
a. 6
b. 24
c. 12
______13. What describes how substances react to form NEW substances?
a. Chemical properties
b. Physical properties
______14. Density, color, and boiling point are examples of:
a. Chemical descriptors
b. Chemical properties
c. Physical properties
______15. What forces hold together the atoms in molecules?
a. Chemical mixtures
b. Chemical bonds
c. Magnetic fields
______16. What is the atomic number tell you about an element?
a. The number of protons
b. The number of neutrons
c. How much mass an atom of that element has
______17. Where are the protons in the atom found?
a. The electron cloud
b. Outside of the atom
c. In the nucleus of the atom
COMPLETE EACH SENTENCE OR STATEMENT:
1. Mixtures in which two or more substances are evenly dispersed are ____________________
mixtures.
2. The attraction between atoms that share electrons results in ___________________ bonds.
3. When electrons are transferred between the atoms of metallic and non-metallic elements,
________________ bonds are formed.
4. Mixtures in which two or more substances are NOT evenly distributed are _______________
mixtures.
5. In a chemical equation, reactants are found on the ____________ side of the arrow and
products are found on the _____________ side of the arrow.
SHORT ANSWER:
6. Name the three subatomic particles found in atoms:
7. Identify the reactants in the following equation: CO + O2
CO2
8. Identify the products in the following equation: CO + O2
CO2
MATCHING
______9. Neutron
a. the smallest unit of an element that still keeps the
properties of that element
______10. Compound
b. anything that has mass and takes up space
______11. Matter
c. atom or molecule that has gained or lost electrons
______12. Molecule
d. this describes the reaction of elements and compounds
in which new elements and compounds are formed
______13. Electron
e. subatomic particle without a charge
______14. Atom
f. two or more chemically bonded elements
______15. Periodic Table
g. negatively charged subatomic particle
______16. Proton
h. smallest unit of an matter that retains chemical
properties
______17. Ion
i. positively charged subatomic particle
______18. Chemical Equation
j. a system for classifying elements
1. Determine the numbers of PROTONS, NEUTRONS and ELECTRONS of the following
elements:
a. Nickel (mass =59)
b. Arsenic (mass =75)
c. Iridium (mass =192)
Protons _______
Protons _______
Protons _______
Neutrons _______
Neutrons _______
Neutrons _______
Electrons _______
Electrons _______
Electrons _______
2. Determine the element NAME and MASS NUMBER:
a. Protons = 26, Neutrons = 30 b. Protons = 17, Neutrons = 18 c. Protons = 48, Neutrons = 64
Element__________________ Element__________________ Element__________________
Mass___________
Mass___________
Mass___________
3. Determine if the following compounds contain ionic or covalent bonds:
a. MnO2 _________________________________
b. CS2 _________________________________
c. PbS _________________________________
d. CO2 _________________________________
4. Determine how many less or extra electrons the following ions have:
a. Pb2+ _______________________
b. Tl3+ _______________________
c. F- _______________________
d. CrO42- _______________________
5. Diagram the following atoms, showing protons + , neutrons
and electrons ( Make sure to DRAW the atom and label the parts)
a. Nitrogen, Mass = 14
b. Beryllium, Mass = 9
P=____
P=____
N=____
N=____
E=____
E=____