Answer:
3.59x10^21 molecules
Explanation:
1mole of a substance contains 6.02x10^23 molecules.
Therefore, 1mole of C8H18 will also contain 6.02x10^23 molecules
1mole of C8H18 = (12x8) +(18x1) = 96 + 18 = 114g.
1mole (i.e 114g) oh C8H18 contains 6.02x10^23 molecules.
Therefore, 0.68g of C8H18 will contain = (0.68 x 6.02x10^23)/114 = 3.59x10^21 molecules
Good idea!maybe I should try that
Answer:
Explanation:
70% (vol/vol) means
cotnaimns 70 %(vol/vol) 70 ml of isoprapnol is there in 100 ml of Rubbing sold alcohol.
if it is 200 ml then obvouly it has the 70*2 =140 ml of isoproanol required.
Total vapor pressure can be calculated using partial vapor pressures and mole fraction as follows:
Here, 
is mole fraction of A, 
is mole fraction of B, 
is partial pressure of A and 
is partial pressure of B.
The mole fraction of A and B are related to each other as follows:
In this problem, A is hexane and B is octane, mole fraction of hexane is given 0.580 thus, mole fraction of octane can be calculated as follows:
Partial pressure of hexane and octane is given 183 mmHg and 59.2 mmHg respectively.
Now, vapor pressure can be calculated as follows:
Putting the values,
Therefore, total vapor pressure over the solution of hexane and octane is 131 mmHg.
Answer:
1. Temperature is the measurement of how hot or cold something is.
agree
2. When something heats up, new energy is created, and when something cools down, energy is destroyed.
disagree
3.When something heats up, it moves faster, and when something cools down, it moves slower.
agree
4. Hotter things have more energy than colder things.
agree
