Effect of Pressure Change

• When there is more pressure (closed), what was the observed color?

  Yellow
• When there is more pressure (closed), what was the shift in equilibrium?

  Backward
• When there is more pressure (closed), what was the explanation?

  Increase in pressure favors less gas; BTB become

  yellow because solution became acidic
• When there is less pressure (open), what was the observed color?

  yellow
• When there is less pressure (open), what was the shift in equilibrium?

  Backward
• When there is less pressure (open), what was the explanation?

  No increase in pressure favors more gas; Color change to yellow because of addition of acid