Which type of chemical reaction absorbs more energy than it releases, breaking a chemical bond?
A. Exothermic
B. Endothermic
What is B. Endothermic (exothermic releases more energy than it absorbs, forming a chemical bond)
100
List some factors that will speed up a chemical reaction:
What is increased pressure, increased surface area, increased temperature, higher concentration or a catalyst
100
What are some signs that a chemical reaction has taken place?
What is odor, change in color, gas, change of energy, and a precipitate forms (but only way to know for sure is if a new substance is formed).
100
T/F: A balanced equation means that the elements and number of atoms have to be the same on both sides of the equation.
What is TRUE!
100
What is the law of conservation of mass?
What is when the reactant mass equals the product mass.
200
Define: catalyst
What is something that speeds up a reaction rate by lowering the activation energy of the reaction (its the opposite of an inhibitor)
200
List some factors that will slow down a chemical reaction:
What is decreased pressure, decreased surface area, decreased temperature, lower concentration, and an inhibitor
200
Wood burned
a. physical
b. chemical
What is b. chemical-because a new substance is formed so there is a change of chemical properties
200
Why is it wrong to change subscripts when balancing an equation?
What is it changes the formula and is no longer the same substance.
200
T/F: Chemical reactions can only release more energy than they absorb.
What is False-a chemical reaction can release or absorb more energy or vice versa.
300
Fill-in-the-blank: All substances have a fixed arrangement of ____________, and only compounds and __________ are substances.
What is atoms/ elements
300
Which type of reaction occurs when sodium reacts with chlorine to produce sodium chloride?
a. synthesis
b. single replacement
c. double replacement
d. decomposition
What is a. synthesis
300
Melting ice.
a. physical
b. chemical
What is a. physical (does not change chemical composition)
300
When balancing equations, the products are to the _________of the arrow.
a. right
b. left
What is a. right (and the reactants to the left)
300
T/F: Both endothermic and exothermic reactions require energy to start.
What is True
400
T/F: If the arrangement of atoms change, that means a reaction has occurred.
What is True
400
Which type of reaction occurs when water (H2O) breaks down to hydrogen and oxygen?
a. synthesis
b. single replacement
c. double replacement
d. decomposition
What is d. decomposition
400
Boiling water
a. physical
b. chemical
What is a. physical
400
Balance this equation by identifying the unlined variable:
P4 + ___O2 = P4O4
What is 2
500
What is defined as the minimum amount of energy needed to start a reaction?
What is activation energy
500
Which type of reaction occurs when Sodium nitrate and aluminium fluoride become sodium fluoride and aluminium nitrate?
a. synthesis
b. single replacement
c. double replacement
d. decomposition
What is c. double replacement
500
Which would burn faster, wood or wood splinters?
What is splinters, because they have less surface area.
500
Is the following equation balanced?
H2 + O = H2O
What is Yes!
500
If you have more substances in container A versus container B, which container will have the greater reaction rates and why?
What is Container A because there is more likelihood of collisions which create a reaction. Greater concentration=faster reaction rates.