Answer:
Vapour pressure of cyclohexane at 50°C is 490torr
Vapour pressure of benzene at 50°C is 90torr
Explanation:
Using Raoult's law, pressure of a solution is defined by the sum of the product sbetween mole fraction of both solvents and pressure of pure solvents.

In the first solution:


<em>(1)</em>
For the second equation:


<em>(2)</em>
Replacing (2) in (1):


-122.5torr = -0.250P°A

<em>Vapour pressure of cyclohexane at 50°C is 490torr</em>
And for benzene:


<em>Vapour pressure of benzene at 50°C is 90torr</em>
The density of the stone is 5 because the formula is mass/volume and the volume is 5 and the mass is 25
Answer:
Determining the pH of substances such as purple grape juice and catsup using test strips can be difficult. Why?
Explanation:
Due to the tartaric acid present in these substances, this is a weak acid and is the predominant type of acid in grapes.
pH meters for these substances, measure the total acidity of the sample and convert it into tartaric acid concentration; The test strips are a qualitative method of measurement and their result can give different opinions.
Answer:
salt is dull and brittle and conducts electricity when it has been dissolved into water, which it does quite easily.
Explanation:
transparent and colourless in crystalline form- rather like ice.