PLEASE HELP! What is the total pressure of a gas mixture containing 20.0 kPa of oxygen, 32.1 kPa of nitrogen and 4.20 kPa of neon?

56.30 kPa

Explanation:

In this case, the pressure of every gas in the mixture is given. Taking the sum of the pressures will give the total pressure of the gas mixture.

Using the Dalton's law of partial pressures, the sum of pressures of each individual gases gives the total pressure of a mixture of gases.

Ptotal= Poxygen + Pnitrogen + Pneon

P-total=20 + 32.1 +4.20 =56.30 kPa

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.