Which compound is a product of the following chemical reaction?

CaCl₂ + 2NaHCO₂ → CaCO₃+2NaCl + H₂O + CO₂

• CaCl₂

• CaCO₃

All atoms of the same element have the same-

• number of neutrons

• atomic number

A change in matter that produces a new substance is —

• chemical change

• physical change

The number of protons in an atom of Neon (Ne)

• 20

• 10

• 21

The chemical equation shows the chemical reactions in plant photosynthesis. How

many different elements are in the equation?

• eight

• three

• two

Each element is different because each element has

• a unique (different) number of protons

• its own group on the periodic table

The above graphic of hydrogen peroxide correctly matches which list?

• Hydrogen- 1, Oxygen- 1

• Hydrogen- 2, Oxygen- 2

• Hydrogen- 2, Oxygen- 1

Atoms have the same number of ___________and __________.

• neutrons and electrons

• protons and electrons

• protons and neutrons

Which example correctly identifies the number of atoms of each element in the

compound CaCO₃?

• Calcium-1, Carbon-1, Oxygen-1

• Calcium-3, Carbon-3, Oxygen-3

• Calcium-1, Carbon-1, Oxygen-3

What is the chemical symbol for the element in the above picture?

• 19

• K

• 39.098