Conservation of Mass and Sample Comparisons

If samples have different properties...

• They are the same substance

• They may be the same substance

• They are not the same substance

• We do not know if they are the same substance or not

If 2 samples are the same color and texture...

• They are the same substance

• They may be the same substance

• They are not the same substance

• Taste them to see if they are the same

We know two substances are the same if...

• They have the same repeating group of atoms

• They have the same number of molecules

• They contain the same types of atoms

• The repeating groups have no more than 2 different atoms

Tags

NGSS.MS-PS1-1

The starting materials in a chemical reaction are called

• remainders

• ingredients

• products

• reactants

The materials resulting from a chemical reaction are called

• units

• promoters

• products

• reactants

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Crystals like diamonds and salt are made of

• simple molecules

• extended structures

• flexible webs

• long wire-like molecules

Tags

NGSS.MS-PS1-1

Which molecule could be produced in the following reaction?

2H₂ + O₂ -->

• CO₂

• NaOH

• HCl

• H₂O

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

All of the atoms present in the products of a chemical reaction come from

• the energy input

• the reactants

• the surroundings

• the relatives

Tags

NGSS.MS-PS1-5

Which of the following is NOT characteristic

of a substance composed of simple molecules

• High melting point

• irregular arrangement of molecules

• weak bonds between molecules

• strong bonds within the molecules

Tags

NGSS.MS-PS1-4

States that matter cannot be created or destroyed

• Law of Universal Existence

• Law of Creation

• Law of Conservation of Chemicals

• Law of Conservation of Matter

Tags

NGSS.MS-PS1-5