1
What is a process that changes substances into new substances
A chemical reaction
The total amount of atoms in the element H2O
What is 3
What number identifies an element on the periodic table?
The Atomic number
Elements are catagorirized in 3 groups. What are they?
Metals, Non-metals, and Mettaloids.
What are synthetic elements?
Elements that are man-made.
What is a solid substances that are formed when 2 liquids are combined in a chemical reaction
PRECIPITATE
The Atomic number of this element is 12. How many protons does it have?
12
Where are protons and neutrons located in an atom reaction
The Nucleus
What is the process or change that doesn’t change substances into new substances considered?
PHYSICAL CHANGE
On the periodic table, how many elements are natural resources?
94
What is the starting substance that goes into a chemical reaction called?
REACTANT
What is the substance that is formed as the result of a chemical reaction?
PRODUCT
Give 3 examples of a physical change
cutting, tearing, crushing, freezing, melting, or other acceptable answers
If a reaction begins with 25 grams of reactants, how much total mass should the products have?
25 grams
What type of charge does each subatomic (part of the atom) particle carry?
Proton+positive
Neutron 0 none or neutral
Electron-negative
What is Exothermic?
A chemical reaction that gives off heat energy
What are 3 examples of a chemical change?
Burning, baking, cooking, digesting, souring milk , rust formation
What are the three main subatomic (parts of the atom) particles
Proton, Neutrons, and Electrons
What is Endothermic?
Endothermic is a chemical reaction that absorbs heat energy
How many total atoms are in 3CO₂?
What is 9
List the 5 ways is it determined that a chemical reaction has taken place
A chemical reaction may be indicated by a change in color, odor, or temperature; the emission of light; and/or the production of a precipitate or gas bubbles
How do scientists answer or represent chemical reactions?
Scientists write chemical equations to represent chemical reactions.
What are POLYMERS
large molecules made of many smaller repeating units linked together in long chains
Write a balanced chemical equation
a + b ...> ab
What is the law of conservation of mass?
The law of conservation of mass states that matter is neither created nor destroyed in chemical reactions. In any chemical reaction, the total mass of the products always equals the total mass of the reactants.