Chemistry Basics
When writing a chemical equation, the substances on the left hand side of the arrow are the _____, while those on the right hand side are the ______.
reactants; products
An exothermic reaction:
A) releases energy into the environment
B) absorbs energy from the environment
A) releases energy to the environment
To balance a chemical equation, it is permissible to adjust the:
A) coefficients
B) formulas of the products
C) subscripts
A) coefficients
How many valence electrons in neon?
8
Write the formula for
potassium (K+1) bonding with iodine (I-1)
KI
Chemical reactions can be represented by using a...
A) chemical change
B) chemical equation
C) chemical formula
B) chemical equation
If the addition of heat is required to make this reaction take place, the reaction must be?
A) endothermic
B) exothermic
A) endothermic
To balance this reaction the coefficient that needs to be placed before the Potassium sulfate is:
Al2(SO4)3 + KOH -> Al(OH)3 + K2SO4
A) 2
B) 3
C) 4
B) 3
How many valence electrons in aluminum?
3
The correct formula for a compound made from potassium (K+1 ) and oxygen (O-2) is:
K2O
Why must a chemical equation be balanced?
obeys the law of conservation of mass
Involving a solid, which would cause a reaction's rate to increase the most?
A) raise the temperature and break the solid into small pieces
B) lower the temperature and break the solid into small pieces
C) raise the temperature and keep the solid in a lump
A) raise the temperature and break the solid into small pieces
When the equation is balanced, the coefficient for sodium chloride would be:
___FeCl2 + _Na2CO3 -> __FeCO3 + _NaCl
A) 6
B) 2
C) 3
B) 2
What is the total number of valence electrons in MgCl2?
16
Write the following for
Iron (III) + CO3 -2 carbonate
Fe2(CO3)3
A group of atoms covalently bonded and carrying a charge, such as SO4 -2 , is called a:
polyatomic ion or radical
A substance that speeds up a chemical reaction is:
A) an inhibitor
B) a really adorable sweet "purr"fect ...catalyst
B) a catalyst
Balance and classify the equation.
Al + HCl -> AlCl3 + H2
Type?
2 Al + 6 HCl -> 2 AlCl3 + 3 H2
Type- Single Replacement
What is the total number of valence electrons in H2SO4 ?
32
In the compound copper II oxide, the roman numeral II indicates
A) The number of valence electrons from copper ions
B) The number of valence electrons from oxygen ions
A) The number of valence electrons from copper ions
The atomic number of an element is determined by the number of this subatomic particle in the atom.
protons
An increase in temperature generally increases the reaction rate because the molecules collide:
A) more frequently and with less energy
B) more frequently and with more energy
C) less frequently but with more energy
B) more frequently and with more energy
Balance & classify the equation.
C2H6 + O2 -> CO2 + H2O
Type?
1 C2H6 + 4 O2 -> 2 CO2 + 3 H2O
Type- Combustion
What is the total number of valence electrons involved in barium chloride ?
16
What is the oxidation number of magnesium as evidenced in the formula MgO?
+2