Answer:
Semi-metals with propeties in between metals and non-metals
<span>The density of the solution =1.05 g/ml.
</span><span>The total mass of the resulting solution is = 398.7 g (CaCl2 + water)
</span>
Find moles of CaCl2 and water.
Molar mass of CaCl2 = 110 (approx.)
Moles of CaCl2 = 23.7 / 110 = 0.22
so, moles of Cl- ion = 2 x 0.22 = 0.44 (because each molecule of CaCl2 will give two Cl- ions)
Moles of water = 375 / 18 = 20.83
Now, Mole fraction of CaCl2 = (moles of CaCl2) / (total moles)
total moles = moles of Cl- ions + moles of Ca2+ ions + moles of water
= 0.44 + 0.22 + 20.83
=21.49
So, mole fraction = 0.44 / (21.49) = 0.02
Guess what !!! density is not used. No need
Answer:
heat
Explanation:
most of the gasoline's energy is released as heat energy rather than kinetic energy on the pistons. this is why a car engine must constantly be cooled by the water to air heat exchanger we call a radiator
Answer:
38.3 miles
Explanation:
First, we <u>convert 1.95 gallons to mililiters</u>:
- 1.95 gallons * = 7380.75 mL
Then we <u>calculate how many grams of octane are available for the reaction</u>, using its density:
- 0.6916 g/mL * 7380.75 mL = 5104.53 g C₈H₁₈
Now we <u>convert octane grams into octane moles</u>, using its molar mass:
- 5104.53 g C₈H₁₈ ÷ 114 g/mol = 44.78 mol C₈H₁₈
Then we <u>calculate how many kJ are produced from the combustion of 44.78 mol C₈H₁₈</u>, <em>if 2 moles produce 10900 kJ</em>:
- 44.78 mol * 10900 kJ / 2 mol = 244032 kJ
We<u> calculate how many seconds is the car available to keep going</u>, <em>if it spends 115 kJ per second</em>:
- 244032 kJ * 1 s / 115 kJ = 2122.02 s
We convert seconds to hours:
- 2122.02 / 3600 = 0.59 hours
Finally we calculate the distance:
- 65 mi/hour * 0.59 hour = 38.3 mi