Chemical Reactions

How many different elements are present in the following chemical formula: CO₂

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-1

How many different elements are present in the following chemical formula: CoSO₄

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-1

How many Hydrogen atoms are present in glucose: C₆H₁₂O₆

• 6

• 12

• 24

• 1

Tags

NGSS.MS-PS1-1

How many Sulfur atoms are in Cr(SO₄)₃?

• 1

• 3

• 4

• 12

Tags

NGSS.MS-PS1-1

Pb(NO₃)₂

Fill in the blanks with the number of atoms of each element.

Pb:

N:

O:

Tags

NGSS.MS-PS1-1

In this image, the symbols to the right of the arrow (in black) are called the_______.

• Products
• Reactants
• Subscripts
• Coefficients

Tags

NGSS.MS-PS1-2

Na + MgF₂ -->  NaF + Mg
What are the reactants?

• Na + MgF₂
• Na
• NaF + Mg
• NaF

All of the following are chemical changes except

• iron rusting
• water evaporating
• wood burning
• food rotting

Tags

NGSS.MS-PS1-2

Coal contains carbon and other elements. Carbon dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?

• The shape of the coal changes
• Oxygen is present
• A new substance is produced
• Coal is made up of more than one element

Tags

NGSS.MS-PS1-2

How many nitrogen atoms are there?

• 4

• 8

• 10

• 20

Tags

NGSS.MS-PS1-1