Download Review Chemistry KEY - cms16-17

Name ____________________________________________________ Period _____ Date ________________________
Chemistry CBA Review
TEKS 5A_Describe the structure of atoms, including the masses, electrical charges, and
locations, of protons and neutrons in the nucleus and electrons in the electron cloud.
1. Identify the parts of an atom:
Valence_Electron___
____
Energy Level______
_Neutron_________
_______
Nucleus__________
_______
Electron__________
_______
2. Fill in the chart below:
Subatomic Particle
Proton
Neutron
Electron
Valence Electron
Proton___________
______
Electrical Charge
Positive
Neutral
Negative
Negative
Mass
1 amu
1 amu
negligible
negligible
Location
Nucleus
Nucleus
Electron Cloud
Outermost Energy Ring
3. The nucleus of an atomA.
B.
C.
D.
Always has the same number of protons and neutrons.
Is positively charged
Is neutrally charged.
Is involved with covalent bonding.
4. What subatomic particle(s) are responsible for almost all of an atom’s mass?
Protons and neutrons
5. Why is the overall charge of the atom neutral?
The number of protons are equal to the number of electrons giving the atom a neutral charge.
6. What is the difference between the atomic number and the atomic mass?
The atomic number tells us the number of protons and electrons, the atomic mass is protons
plus the number of neutrons.
7. What is the basic particle from which all elements are made?
Atoms
8. What is the equation for calculating atomic mass?
Protons + neutrons
Name ____________________________________________________ Period _____ Date ________________________
9. Draw a Bohr Model of a Silicon atom.
TEKS 5B_ Identify that protons determine an element’s identity and valence electrons
determine its chemical properties, including reactivity.
10. The atomic number of an atom is determined by the number of _____________.
A.
B.
C.
D.
Protons
Neutrons
Electrons
Isotopes
11. Why are valence electrons important?
Valence electrons are used for bonding, therefore they determine how elements will react with
with other substances.
TEKS 5C_Interpret the arrangement of the Periodic Table, including groups and periods to
explain how properties are used to classify elements.
12. In the periodic table the horizontal rows that extend across the table are called periods
.
13. Name the elements that Carbon has properties most similar to:
Silicon, Germanium, Tin, and Lead
14. Explain why Lithium, Potassium, and Sodium have similar properties:
They are found in the same group/family/column.
15. An element has mass number of 32 and an atomic number of 16. How many neutrons does an
atom of this element have?
16
16. An element has an atomic number of 36 and an atomic mass of 84. How many electrons would
an atom of this element have?
36
17. The nucleus of an atom contains 13 protons. To be electrically neutral, the atom must also have:
13 electrons
Name ____________________________________________________ Period _____ Date ________________________
18. Which of these sets of atomic numbers represents a group?
A.
B.
C.
D.
11, 12, 13
19, 29, 35
6, 32, 50
9, 18, 53
19. Which of these sets of atomic numbers represents a period?
A.
B.
C.
D.
Li, Na, K
B, Sa, Si
B, O, Ne
Co, P, S
20. Elements C, Si, Ge, Sn, and Pb have similar:
A.
B.
C.
D.
Atomic numbers
Atomic symbols
States of matter
Physical and chemical properties
21. Highlight the element that has a mass number of 27.
Element
Sulfur
Aluminum
Cobalt
Number of Protons
16
13
27
Number of Neutrons
16
14
32
TEKS 5D_Recognize that chemical formulas are used to identify substances and determine
the number of atoms of each element in chemical formulas containing subscripts.
TEKS 5E_Investigate how evidence of chemical reactions indicate that new substances with
different properties are formed.
22. Complete the table by marking whether the example is a physical or chemical reaction:
Example
Ice cream melting
Iron rusting
Metal pounded into a sheet
Sugar dissolving in water
Paper burning
Hydrochloric Acid and a
metal react to form a new
substance
Water freezing to form ice
Physical Reaction
X
Chemical Reaction
X
X
X
X
X
X
Name ____________________________________________________ Period _____ Date ________________________
23.For the following chemical reactions, circle the subscripts and draw a box around the coefficients.
2 NaOH + H2CO3 ---> Na2CO3 + 2 H2O
I2 + 2KCl  2KI + Cl2
24.There are a number of chemical formulas that you must know. Complete the following table by
writing either the common name or the chemical name.
Chemical Formula
H2O
CO2
C6H12O6
O2
NaCl
H2SO4
Name
water
Carbon Dioxide
Glucose
Pure oxygen
Sodium chloride (salt)
Sulfuric Acid (dihydrogen sulfate)
Use the model below for Questions 25-27:
25. Using the model above, what could be the chemical formula for nitric acid:
A.
B.
C.
D.
HNO
H2NO3
HNO3
HN2O3
26. What is the total number of atoms : ___5_______________________
27. What is the total number of elements: ___3_____________________
Looking at the equation below, answer Questions 28 and 29:
2NaOH + H2CO3 ---> Na2CO3 + 2 H2O
28. List the reactants:
2NaOH and H2CO3____________________________________________
29. List the products:
Na2CO3 and 2H2O________________________________________
Name ____________________________________________________ Period _____ Date ________________________
30. What happens when substances react chemically to produce new substances?
The substances will have a new identity and new and different chemical and physical
properties will form.
31. Explain the difference between reactants and products. Include where in the equation they
would be found.
Reactants form products. The reactants are what you start with and the product is the end
result.
The reactants are found before the arrow and the products are found after the arrow.
32. List each element in the following compounds and the number of atoms of each element
present and the total number of atoms.
a. C6H8O6 (Vitamin C):
i. Elements: C, H, and O_____________________________________
ii. Atoms: C=6, H=8, and O=6 Total number of atoms=20___________
b. C8H10O2N4H2O (Caffeine):
i. Elements: C, H, O, N______________________________________
ii. Atoms: C=8, H=12, O=3, N=4 Total number of atoms=27__________
c. 3NaAl(SO4 )2 (In baking powder):
i. Elements: Na, Al, S, O_____________________________________
ii. Atoms: Na=3, Al=3, S=6, O=24 Total number of atoms=36______________
TEKS 5F_Recognize whether a chemical equation containing coefficients is balanced or not
and how that relates to the law of conservation of mass.
33. Determine whether the following equations are balanced or unbalanced. If unbalanced,
balance the equation.
_Balanced___________
I2 + 2KCl  2KI + Cl2
_Unbalanced_________
O2 + Al  Al2O3
3O2 + 4Al  2Al2O3
_Balanced___________
2H2O  2H2 + O2
_Unbalanced_________
HCl + NaOH  4 H2O + NaCl
4HCl + 4NaOH  4H2O + 4NaCl
Name ____________________________________________________ Period _____ Date ________________________
34. What is the balanced equation for photosynthesis?
6CO2 + 6H2O  C6H12O6 + 6O2
35. Is the following chemical equation balanced or unbalanced? What does the large number
represent?
Fe + 2HCl  FeCl2 + H2
Balanced
The large number (2) indicates the number of molecules for that substance.
36. What does the Law of Conservation of Mass state?
Mass/Matter is neither created or destroyed in an ordinary chemical reaction.
37. What is changed to balance an equation?
The coefficients.