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Chemistry

1 answer:

il63 [147K]2 years ago

4 0

Answer:

Demonstration 1 showed a chemical change because a new gaseous substance was formed, and demonstration 2 showed a physical change because liquid water became water vapor.

Explanation:

Chemical changes alter the chemical makeup of a subject, and a physical change only alters the appearance of a subject, not the chemical makeup.

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The mole fraction of hcl in a solution prepared by dissolving 5.5 g of hcl in 200 g of c2h6o is ________. the density of the sol

Thepotemich [5.8K]

The answer:
all that we search for is the number of mole of HCl and the number of mole of C2H6O

M(HCl) = 5.5g/ mole of HCl , so mole of HCl = 5.5/M(HCl), where M(HCl) is the molar mass.
M(HCl) = 1+ 36.5= 37.5

moles of HCl = 5.5/37.5=0.14

M(C2H6O) = 200g / moles of C2H6O, so moles of C2H6O=200g / M(C2H6O)

M(C2H6O)= 2x12+ 6 + 16=46,

moles of C2H6O=200g / 46 =4.35 moles

the sum of the moles is 0.14 + 4.35 = 4.501 moles

finally, The mole fraction of hcl in a solution prepared by dissolving 5.5 g of hcl in 200 g of c2h6o is 0.031

because it can be found by 0.14 / 4.501= 0.031

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3 years ago

IS IT BETTER OR WORSE TO WORKOUT/EXERCISE IN DARK OR LIGHT COLORED CLOTHING?

soldi70 [24.7K]

Answer:

Dark clothing

Explanation:

Dark clothing like black absorbs/locks in heat. Since exercise is to burn and tonify our body from unwanted fat it is important to sweat. This is where heat comes in and helps you sweat

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3 years ago

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Soda pop is carbonated with CO2. Mark puts one bottle of soda pop in the refrigerator and leaves the other out in the hot sunlig

fomenos

Answer:

The one left in the hot sunlight.

Explanation:

The solubility of gases decreases when temperature increases. The gas in the soda pop (CO2) left in the sun will not stay dissolved as much as the on left in the refrigerator.

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