Category 1
What is a common sign of a chemical reaction?
a. Emission of Light or Heat
b. Freezing juice into ice
c. Boiling water
d. Cutting a piece of paper
A ________ is a charged atom that forms as a result of that atom gaining or losing electrons.
ion
Which of the following is an ionic compound?
a. H2O
b. CO2
c. NaCl
d. CH4
c. NaCL
Which of the following is OT a sign of a chemical change?
a. Cutting of a piece of paper
b. releasing light and heat
c. Release of gas
d. Burning wood
a. Cutting of a piece of paper
The ____________ states that atoms want to have eight electrons in their outer shell.
Octet rule
Which of the following would you NOT expect to form a compound?
a. Beryllium
b. Nitrogen
c. Chlorine
d. Argon
d. Argon
Calcium will form a(n) ________ (cation/anion), while Sulfer will form a(n) __________ (cation/anion).
Cation, Anion
The properties of a compound are identical to the properties of the elements that makeup the compound. True or False?
False
A ______________ (chemical reaction/chemical formula/chemical subscript) is the process by which the atoms of one element are rearranged to form new substances.
Chemical Reaction
Which of the following is a sign of a chemical change?
a. Temperature change without reaction
b. Change of state
c. Color change during a reaction
d. Dissolving in water
c. Color change during a reaction
Which observation suggests a chemical reaction?
a. Heating sugar until it caramelizes
b. Formation of a precipitate
c. Dissolving salt in water
d. Melting ice cubes
a. Heating sugar until it carmalizes
Which of the following is a covalent compound?
a. Water (H2O)
b. Calcium Oxide (CaO)
c. Iron (lll) Oxide (Fe2O3)
d. Sodium Chloride (NaCl)
a. Water (H2O)
When is an atom most stable?
a. When it has a full outer shell of electrons
b. When it has a full first shell of electrons
c. When it has a complete number of protons
a. When it has a full outer shell of electrons
Which of the following BEST explains why atoms form compounds?
a. To have a full shell of protons
b. to gain have a full outer shell of neutrons
c. to have a full outer (valence) shell of electrons
d. to have more electron energy levels
c. to have a full outer (valence) shell of electrons
Which compound is made of a metal and a non-metal?
a. N2
b. MgO
c. Fe
d. O2
b. MgO
Which of the following elements violates the octet rule?
a. Hydrogen and Helium
b. Helium and Phosphorus
c. Hydrogen and Oxygen
d. Helium and Carbon
a. Hydrogen and Helium
What indicates a new substance has been formed?
a. Production of Gas bubbles
b. Change in Temperature only
c. Mixing Colors
d. Dissolving of solids
a. Production of gas bubbles
CO2
a. The compound contains two atoms of carbon but one atom of oxygen
b. the compound contains one atom of carbon and one atom of oxygen
c. the compound contains one atom of carbon and two atoms of oxygen
c. the compound contains one atom of carbon and two atoms of oxygen
Identify the covalent compound from the list.
a. Methane (CH4)
b. Ammonium sulfate (NH4(2S04))
c. Berylium oxide (BeO)
c. Lead (II) nitrate (Pb(NO3)2)
Methane (CH4)
Which of the following is a sign of a chemical change?
a. breaking a window
b. water freezing to ice
c. cutting paper
d. milk spoiling
d. milk spoiling