WorksheetsChemistry Test review
Total questions: 35
Worksheet time: 3hrs 55mins
In a chemical formula, the number of each type of atom in the compound is shown by numbers called ____.
superscripts
oxidation numbers
chemical symbols
subscripts
Sodium is an atom represented as Na+. What does the “+” represent?
The plus sign means it can combine with almost every element found on the periodic table.
Sodium has a tendency to gain a valence electron when it becomes an ion.
Sodium has a tendency to lose a valence electron when it becomes an ion.
One positive sign is listed because it only takes one electron to make the atom neutral.
The energy of an electron __________ as it moves further away from the nucleus
increases
decreases
What is the ionic compound formed between K and F?
KF
KF2
K2F
K2F2
Nitrogen will form which of the following ions?
N-5
N+5
N-3
N
How many electrons are needed in the outer energy levels of an atom to be stable?
2
4
6
8
The chemical formula for sodium sulfate is Na2SO4. How many sulfur atoms are in the formula for sodium sulfate?
1
6
5
7
Serotonin is a chemical substance that acts as a neurotransmitter. It helps relay messages in the human brain. The formula for one molecule of serotonin is shown below.
C10H12N2O
How may atoms in all are in a molecule of serotonin?
10
24
25
100
A student observes some sugar as it is heated and burns. The student concludes that a chemical reaction has occurred. Which of the following observations about the burning sugar provides evidence of a chemical reaction?
Heat is added to the sugar crystals.
The temperature of the sugar increases
The sugar melts and becomes a liquid.
Gas is produced as the sugar turns black.
A teacher asks a student to write the chemical equation for photosynthesis. The student's response is shown below
CO2 + H2O ---> C6H12O6 + O2
The equation is not balanced correctly. Which of these is a balanced equation for photosynthesis?
12CO2 + H2O ---> C6H12O6 + O2
CO2 + 9H2O ---> C6H12O6 + O2
CO2 + H2O ---> 3C6H12O6 + O2
6CO2 + 6H2O ---> C6H12O6 + 6O2
Hay is made up of organic compounds. What are the main elements in many organic compounds?
Helium, carbon, sodium
Carbon, hydrogen, oxygen
Sodium, hydrogen, nitrogen
Radon, oxygen, helium
An ion is an atom that has gained or lost _____.
electrons
neutrons
protons
metals
What property determines the identity of the element Mercury?
Mercury is located in Group 12
An atom of Mercury has 80 protons
An atom of Mercury has 120 neutrons
Mercury is liquid at room temperature and normal pressure
CaCO3 ---> CaO + CO2
In the chemical reaction shown above, the products are best classified as
two elements
two compounds and one element
Two compounds
one element and one compound
Which is NOT found in the nucleus of an atom?
Neutrons
Protons
Atomic Number
Electrons
Which of the following best describes an electron?
It has no charge and about the same mass as a proton
It has a negative charge and much less mass than a proton
It has a positive charge and much more mass than a neutron
It has a negative charge and about the same mass as a neutron
According to the periodic table, Which is the most accurate model of Boron?
a
b
c
d
Which of the following is represented in the graphic?
Sulfur
Chlorine
Argon
Germanium
An atom consists of 12 protons, 12 electrons, and 12 neutrons. Which of the following can be used to identify the element?
Protons
Electrons
Neutrons
Atomic Mass
When determining an element's identity, what is the most important subatomic particle to examine?
Neutrinos
Protons
Neutrons
Electrons
In the equation, how many atoms are in the oxygen molecule?
2
0
1
3
Which of these formulas contain equal numbers of nitrogen atoms?
Formulas I and III
Formulas II and III
Formulas I and IV
Formulas I, II, and V
Which of the following formulas contain the same number of oxygen atoms?
I & II
II & IV
I, II, III
I, II, IV
Hydrogen decomposes quickly when exposed to light. The reaction for decomposing Hydrogen peroxide is:
What is the mass of H2O in the reaction?
24.11g
66.99g
21.44g
48.22g
Which of the following models best demonstrates the law of conservation of mass?
According to the Chemical Compounds table above, how many atoms of hydrogen are in Ethanol?
0
2
5
6
According to the Chemical Compounds table above, how many total atoms are in Glucose?
3
18
24
432
Which subatomic particle has the least mass, less than 1 amu?
Neutrons
Electrons
Proton
Nucleus
An atom of a certain element is solid at room temperature, very stable, conducts electricity, and is magnetic. This atom has an atomic number of 26 and a mass number of 56.
How many neutrons are in this atom?
26
30
56
82
How many HCl molecules do you need to balance this equation?
Mg + __HCl ---> MgCl2 + H2
1
2
3
4
Which subatomic particles have approximately the same mass of 1 amu?
Electrons & Neutrons
Electrons & Protons
Neutrons & Protons
Proton and neutrino
If my charge becomes 2+ what does that say about me?
I am losing 2 electrons
I have an atomic # of 2
I am stealing 2 electrons
I am in period 2
The substances listed on the right side of a chemical equation are the
Products
Precipitates
The substances listed on the left side of a chemical equation are the
Reactants
Products
What is the nucleus charge of Bromine?
+35
-35
-7
7
