Chemistry B Exam

What is the molar mass of B₂(CO₃)₃?

• 81.632 g/mol
• 94.842 g/mol
• 38.822 g/mol
• 201.648 g/mol

What is Half-life?

• The amount of time it takes for some of the nuclei in a sample of the isotope to decay
• The amount of time it takes for half the electrons in a sample of the isotope to decay
• The amount of time it takes for half the nuclei in a sample of the isotope to decay
• the amount of time it takes to double the nuclei in a sample of the isotope to decay

Tags

NGSS.HS-PS1-8

What is emitted during Alpha Radiation?

• A helium nuclei.
• A full helium atom

• Gamma Rays.
• Positrons

Tags

NGSS.HS-PS1-8

What is the percent error of the following experiment?

Theoretical Yield: 3.3 grams

Actual Yield: 2.5 grams

• 24%

• 76%

• 12%

• 56%

What is the percent yield of the following experiment?

Theoretical Yield: 3.3 grams

Actual Yield: 2.5 grams

• 24%

• 76%

• 12%

• 56%

The substances listed on the right side of a chemical equation are the

• Yields
• Reactants
• Products
• Precipitates

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

This reaction is at equilibrium. Which of the following would cause more Hydrogen to be produced?

Co(H₂O)₆ + HCl + Heat <-------> CoCl₄ + H₂O + H₂

• Remove H₂ as it is produced.

• Increasing the heat.

• Adding more HCl.

• Increasing the concentration of the reactants.

• All of these will make more Hydrogen be produced.

Tags

NGSS.HS-PS1-5

What are the correct formulas and coefficients for the products of the following single-replacement reaction?

Mg + Al(OH)₃ →

• No Reaction

• Al + Mg(OH)₃

• Al + Mg(OH)₂

• MgAl + (OH)₃

Tags

NGSS.HS-PS1-2

What is the percent Oxygen in Ca(OH)₂?

• 43.18%

• 56.82%

• 100%

• 32g

What type of equation is this?

Ca(OH)₂ + HNO₃ → Ca(NO₃)₂ + H₂O

• Addition

• Decomposition

• Single Displacement

• Double Displacement