A vessel of 120ml capacity contains a certain amount of gas at 35°C and 1.2 bar pressure. The gas is transferred to another vessel of volume 180ml at 35°C. What would be its pressure

Given parameters:

Initial volume  = 120ml

Initial temperature  = 35°C

Initial pressure  = 1.2bar

Final volume  = 180ml

Final temperature  = 35°C

Unknown:

Final pressure  = ?

To solve this problem, we apply the combined gas law. The expression is given below;

Where P₁ is the initial pressure

           P₂ is the final pressure

          V₁ is the initial volume

          V₂ is the final volume

          T₁ is the initial temperature

           T₂ is the final temperature

We need to convert the parameters to standard units

take the volume to dm³;

      1000ml  = 1dm³

      120ml  = dm³  = 0.12dm³ = initial volume

Final volume;

      1000ml = 1dm³

      180ml  = dm³  = 0.18dm³

Now, the temperature;

       K  = 273 + °C

Initial temperature  = 273 + 35  = 308k

Final temperature  = 308k

We then input the parameters into the equation;

       Solving for P₂;

     P₂  = 0.8bar

The new pressure or final pressure in the vessel is 0.8bar

the answer

explanation:

the capillary tube was too close to the bottom of the beaker.

the ruler may have moved.

water got into the capillary tube.

the temperature was not allowed to equilibrate in the 2-4 minutes.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.