.:Chemical Reactions:.
Which of these is the correct balanced equation for the reaction between potassium and water?
2K(s) + 2H2O(l) → 2KOH(aq) + H2(g)
Look at this unbalanced symbol equation: Na + H20 → NaOH + H2. Which of these is the correct balanced equation?
2Na + 2H2O → 2NaOH + H2
Az
Alka Seltzer
Which halogen is a liquid at room temperature?
Bromine
C
Carbon
Co2
Carbon Dioxide
C3O3
Carbon Monoxide
Bubbles form
Chemical change
Change in color
Chemical change
Solid forms from 2 liquids mixing
Chemical change
Cr
Chromium
Cr2O3
Chromium Dioxide
Cl
Clorhide
Mixing baking soda and vinegar is an example of an endothermic reaction. If you were holding a beaker while this chemical reaction took place, then you would expect it to feel _______ after the reaction was complete.
Colder
Heat is a form of what?
Energy
Which of the following correctly describes changes in energy during a chemical reaction?
Energy may be either absorbed or released during a reaction
Cellular respiration is an example of a chemical reaction where energy is released. Which of the following is a reaction where energy is released?
Exothermic reaction
Iron and chlorine gas reacts to form Iron chloride
Fe +Cl2 → FeCl3
Which is a product in this equation? 6CO2 + 6H2O —> C6H12O6 + 6O2.
Glucose
What is the formula for a molecule of hydrogen?
H2
Density
How much matter is in matter
H
Hydrogen
What gas is always produced when a group 1 metal reacts with water?
Hydrogen
2H2s
Hydrogen Sulfide
Fe
Iron
What is the formula for potassium hydroxide?
KOH
What is the formula of the alkali produced when lithium reacts with water?
LiOH
What is the formula for sodium bromide?
NaBr
O
Oxygen
Ag
Silver
Ag2S
Silver Sulfide
Ag2s
Silver Sulfide
S
Sulfur
When a color change happens, a chemical reaction must have occurred.
True
+
Used to separate multiple reactants or products
H2O
Water
Zn
Zinc
Exothermic
accompanied by the release of heat. (hotter)
What name is given to the elements in group 1?
alkali metals.
Which halogen(s) will displace bromine from a solution of potassium bromide?
chlorine
Scientists observe that when lithium reacts with water, two new substances are formed (lithium hydroxide and hydrogen). They predict that the substances formed will have:
different properties than lithium and water have separately.
Two reactants are mixed in a test tube, and the test tube becomes very warm. This is a sign of a transfer of _____ taking place.
energy
"Meals, Ready to Eat" are an instant hot meal developed by the U.S. military for troops. The meal heats up when water is added to the magnesium metal tray because the chemical reaction between water and magnesium is an _________.
exothermic reaction
→Pt
formula written above the arrow is used as a catalyst in the reaction
(g)
gas
When zinc metal is mixed with hydrochloric acid, what is produced?
gas
(l)
liquid
When a chemical reaction takes place, the reaction must end with the same _____________ it began with.
number of atoms
(aq)
reactant or product in an aqueous solution (dissolved in water)
The _____ oxide turned to the silver metal when mercury (II) oxide was heated.
red
What color is Mercury (II) Oxide?
red
⇄
replaces the yield sign for reversible reactions that reach equilibrium
Endothermic
requiring the absorption of heat. (colder)
(s)
solid
→Δ
triangle indicates that the reaction is being heated
What color is lead(II) iodide?
yellow
→
yield sign; separates reactants from products
