Which list of the phases of H₂O is arranged in order of increasing entropy?

• ice, steam, and liquid water
• ice, liquid water, and steam
• steam, liquid water, and ice
• steam, ice, and liquid water

An open flask is half filled with water at 25^oC. Phase equilibrium can be reached after

• more water is added to the flask
•  the flask is stoppered
• the temperature is decreased to 15^oC
•  the temperature is increased to 35^oC

Tags

NGSS.HS-PS3-4

 Given the equation for a system at equilibrium:
N₂(g) + 3H₂(g) <--> 2NH₃(g) + energy
If only the concentration of N₂(g) is increased, the concentration of

• NH₃(g) increases
• NH₃(g) remains the same
• H₂(g) increases
• H₂(g) remains the same

Tags

NGSS.HS-PS1-5

Given the reaction at equilibrium: 
C₂ + D₂(g) <-->2 CD(g) + energy
Which change will cause the equilibrium to shift?

• increase in pressure
• increase in volume
• addition of heat
• addition of a catalyst

Tags

NGSS.HS-PS1-6

Given the accompanying potential energy diagram for a reaction:
Which interval on this diagram represents the difference between the potential energy of the products and the potential energy of the reactants?

• 1
• 2
• 3
• 4

Tags

NGSS.HS-PS1-4

A sample of helium gas is in a sealed, rigid container. What occurs as the temperature of the sample is increased?

•  The mass of the sample decreases
• The number of moles of gas increases.
• The volume of each atom decreases.
• The frequency of collisions between atoms increases.

Tags

NGSS.HS-PS3-2

 Given the equation representing a reaction at equilibrium:
2SO₂(g) + O₂(g) <--> 2SO₃(g) +HEAT
Which change causes the equilibrium to shift to the right?

• adding a catalyst
•  adding more O₂(g)
• decreasing the pressure
• increasing the temperature

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-6

Given the potential energy diagram for a chemical reaction:
(see image)
Which numbered interval represents the heat of reaction?

• 1
• 2
• 3
• 4

Tags

NGSS.HS-PS1-4

The solid and liquid phases of water can exist in a state of equilibrium at 1 atmosphere of pressure and a temperature of

•  0^oC
• 100^oC
•  273^oC
•  373^oC

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

In most aqueous reactions as temperature increases, the effectiveness of collisions between reacting particles

•  decreases
•  increases
• remains the same

Tags

NGSS.HS-PS1-5