Question | Answer |
what is needed to start a chemical reaction? | Activation energy |
you read the_______ as yields in a chemical equation or formula. what belongs in the blank? | Arrow |
Which way of these two means the alteration chemical properties of matter?Conservation of mass or chemical changes | chemical changes |
what changes energy or changes in properties of matter? | chemical reactions |
which one belongs in the sentence below?
_____________ are a shorter and easier way to show chemical reactions by using symbols instead of words
Coefficient or Chemical Equations | Chemical Equations |
the amount of matter can or can't change?
PS the term is known as Conservation of mass | can |
When a compound breaks down into a simpler substances it is called what? | Decomposition reaction |
What kind of reaction shows that a chemical reaction took place according by energy? | Endothermic reaction |
What kind of reaction shows that a chemical reaction took place according by releasing heat? | Exothermic reaction |
what alters only the physical properties of matter? | Physical change |
a solid that forms from a solution during a chemical reaction is called a _______________ | precipitate |
the materials you have after a chemical reaction is called the
a. subscripts
b. reactants
c. products
d. all of the above | products |
the materials before a chemical reaction are called __________ | reactants |
one part of a compound is displaced is what | Replacement reaction |
solid liquid and gases and plasmas are __________ | states of matter |
_________ are the number in a Chemical Equation tells us how many atoms are in that element or molecule | subscripts |
two substances combine to form a compound this is called_________ | synthesis raction |
what are changes in energy are called what | characteristics of chemical reaction |
a number placed in front a of a atom number is called | coefficient |