Chemical reactions

Is the following chemical equation balanced or unbalanced: P₄ + 3O₂ --> 2P₂O₃

• balanced

• unbalanced

Is the following chemical equation balanced or unbalanced: 2Fe + 3H₂SO₄ --> Fe₂(SO₄)₃ + 2H₂

• balanced

• unbalanced

How many atoms of Oxygen are present in the reactants of the following chemical equation: 2NO₂ --> N₂ + 2O₂

• 8

• 2

• 4

• 1

Which of the following models best demonstrates a balanced chemical equation?

• F

• G

• H

• J

The formula below represents the most common carbohydrate known as glucose (or sugar). Which information can be determined from the chemical formula?

C₆H₁₂O₆

• The structural arrangement of the atoms in a glucose molecule

• The color of a glucose molecule

• The size of a glucose molecule

• The number of atoms of each element in a glucose molecule

For an investigation a student poured a blue solution of CuSO₄ into a beaker. The student placed a shiny, silver-colored strip of zinc metal in the solution and observed the changes.

The student inferred that a chemical reaction occurred. What evidence supports this inference?

• A dark solid formed on the zinc metal.

• The zinc metal remained silver-colored and shiny

• The CuSO₄ solution turned blue when the zinc metal was added.

• None of these

Which of the following equations demonstrates an actual chemical reaction that forms a new substance?

• A

• B

• C

• D

Which of these formulas contain 2 atoms of nitrogen?

• Formulas I and II

• Formulas III and IV

• Formulas II and V

• Formulas I, II, and V

The reactants are on the left side of the chemical equation.

• True
• False

Tags

NGSS.MS-PS1-5

Two clear colorless solutions were combined.
The student observed that the temperature changed from 25 •C to 23 •C when the solutions were combined and that a white substance rapidly formed and settled to the bottom of the container. What most likely happened to produce these results?

• One of the original compounds came out of solution
• The solutions reacted chemically
• Some of the water froze into ice crystals
• Rapid evaporation of water occurred, leaving a solid

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4