Shared Flashcard Set

Details

Test Review
Chapter 2 - Chemistry of Matter
24
Science
8th Grade
01/15/2006

Additional Science Flashcards

 


 

Cards

Term
What is a reactant?
Definition
substance that enters into a chemical reaction
Term
What is a product?
Definition
substance produced by a chemical reaction
Term
What is a catalyst?
Definition
substance that increases the rate of a chemical reaction without being changed by the reaction
Term
What is the number that describes how many molecules of a substance are involved in a chemical reaction?
Definition
coefficient
Term
Define synthesis reaction.
Definition
Two or more substancese combine to form a new more complex substance
Term
What is the letter formula for a synthesis reaction?
Definition
A + B -> C
Term
Define decomposition reaction.
Definition
a complex substance breaks down into two or more simpler substances
Term
What is the letter formula for a decompostion reaction?
Definition
C -> A + B
Term
Define single replacement reaction.
Definition
An uncombined element replaces an element that is part of a compound
Term
What is the letter formula for a single replacement reaction?
Definition
A + BX -> AX + B
Term
Define double replacement reaction.
Definition
Different atoms in two different compounds replace each other.
Term
What is the letter formula for a doubler replacement reaction?
Definition
AX + BY -> AY + BX
Term
What does increasing the temperature do to the rate of a chemical reaction?
Definition
speeds it up
Term
In the formula 5C H O
6 12 6,

how many atoms of hydrogen are there?
Definition
60
Term
What is the name for an expression in which symbols and formulas are used to represent a chemical reaction?
Definition
chemical equation
Term
Compare and contrast endothermic and exothermic reactions.
Definition
Endothermic= chemical reaction in which energy is absorbed.

Exothermic= chemical reaction in which energy is released.
Term
What is collision theory?
Definition
The rate of a reaction is affected by four factors: concentration, surface area, temperature and catalyst.
Term
What is activation energy?
Definition
energy required for a chemical reaction to take place.
Term
What does decreasing surface area do to reaction rate?
Definition
slows it down.
Term
How does concentration of reactants effect reaction rate?
Definition
a high concentration rate means there are many particles per unit volume so more collisions may occur.
Term
Compare and contrast physical and chemical changes.
Definition
physical= just a change of form where it could go back to the original form

chemical= changes into a new form and cannot be reversed.
Term
How are the law of conservation of mass and the balancing of chemical equations related?
Definition
because the number of atoms of each element remains the same (like in a chemical equation the atoms have to ballance out at the same time)
Term
Give a step by step description of how to balance an equation. At least 4 steps.
Definition
1. Write a chemical equation with correct symbols and formulas.

2. Count the number of atoms of each element on each side of the arrow.

3. Balance atoms by using coefficients

4. Check your work by counting atoms of each element.
Term
List all of the information a balanced chemical equation provides. At least 4 things.
Definition
The element, the type of reaction , the number of molecules, the number of atoms, the products, the reactants.
Supporting users have an ad free experience!