1
a chemical symbol for an element?
Anything on PT
Which element is found in all organic compounds?
Carbon
In the compound NaCl, what element does "Na" represent?
Sodium
The periodic table is organized primarily by:
Atomic number
In the equation:
CH₄ + 2O₂ → CO₂ + 2H₂O,
How many oxygen atoms are on the reactant side?
2
In the chemical equation 2H₂ + O₂ → 2H₂O, how many hydrogen atoms are on the product side?
4
Substances made of two or more different elements chemically joined together.
Compounds
Which describes the rearrangement of atoms in a chemical reaction?
Atoms combine in new ways to form different substances
What does the subscript “2” in H₂O mean?
2 hydrogen atoms
The big number in front of a chemical formula that shows how many molecules there are (like 2H₂O means two water molecules).
Coefficient
The smallest unit of an element that still retains its properties is a(n)
An atom
Which of the following is an example of a compound?
a) O₂
b) H
c) H₂O
d) Na
H₂O
Which of the following best represents the Law of Conservation of Mass?
Mass before a reaction is equal to mass after the reaction
Which of these is a product of photosynthesis?
C₆H₁₂O₆
Ending substances in a chemical reaction.
Product
A symbol that shows how many atoms of an element are in a molecule.
subscript
A representation of a chemical reaction using symbols and formulas.
Chemical Equation
Starting materials in a chemical reaction.
Reactant
The smallest unit of matter.
Atom
In what ways can we identify when a new substance has been formed?
bubbles, temperature change, etc.
If you start with 12 g of hydrogen and 96 g of oxygen to form water, what will be the total mass of the water produced? Show your reasoning.
108g
The process plants use to turn sunlight, carbon dioxide, and water into food (glucose) and oxygen.
Photosynthesis
Which best explains why mass is conserved in chemical reactions?
Atoms are rearranged but not lost
matter is not created or destroyed, only rearranged
Law of conservation of mass
A chemical formula tells you:
How many atoms of each element are present