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3 years ago

Which of the following processes releases heat? Evaporation Freezing Melting Sublimation . I know for sure it is not freezing.

2 answers:

Ivan3 years ago

6 0

Freezing process release heat that is the process is exothermic . In addition condensation process also is exothermic. When substance losses heat energy the attractive force between atom slow down and hence reduces their mobility.Example when water turn to a ice cubes the reaction releases heat energy.

gayaneshka [121]3 years ago

4 0

During freezing heat will be released. Normally we wont think like that ,but the reality is during freezing the heat get released. the liquid water will have more energy than the frozen water .so during this transition the energy of the water get released as the latent heat. Basically when we need to reduce the temperature ie. freezing a substance, the heat already absorbed in the substance should be released out of the substance.

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The total pressure in a container is 37.9 psi. There are two gases in the container. Gas A exerts a pressure of 18.4 psi. What i

Andrei [34K]

Answer:

19.5

Explanation: using dalton law pt=p1+p2+p3...

the total pressure is 37.9 so to get pressure of gas b subtract pressure of gas a from total pressure.37.9-18.4 gas b equals 19.5

4 0

2 years ago

If 5.100 g of c6h6 is burned and the heat produced from the burning is added to 5691 g of water at 21 °c, what is the final temp

emmasim [6.3K]

C6H12 = 6x12 + 6x1 = 78.
The equation indicates that 2x78 = 156g benzene will produce 6542kJ.
Using proportions you can then calculate that
x/6542kJ = 7.9g / 156g
x = 331.3kJ = 331300J.

heat = mass x ΔT x 4.18J/g°
ΔT = 331300J / (5691g x 4.18J/g°) = 13.9°

final temp = 21 + 14° = 35°C

4 0

3 years ago

Which label belongs in the region marked X?

lubasha [3.4K]

Answer:

A) involves changes in temperature

Explanation:

The figure is missing, but I assume that the region marked X represents the region in common between Gay-Lussac's law and Charle's Law.

Gay-Lussac's law states that:

"For an ideal gas kept at constant volume, the pressure of the gas is directly proportional to its absolute temperature"

Mathematically, it can be written as

$p\propto T$

where p is the pressure of the gas and T its absolute temperature.

Charle's Law states that:

"For an ideal gas kept at constant pressure, the volume of the gas is directly proportional to its absolute temperature"

Mathematically, it can be written as

$V\propto T$

where V is the volume of the gas and T its absolute temperature.

By looking at the two descriptions of the law, we see immediately that the property that they have in common is

A) involves changes in temperature

Since the temperature is NOT kept constant in the two laws.

7 0

2 years ago

Circle only those of the following reactions that are redox reactions:

Citrus2011 [14]

Answer: options B,D and F

Explanation:

Since redox reactions are those which involves both oxidation and reduction

In B , Cu is oxidized and S gets reduced

D, Na gets oxidized and hydrogen gets reduced

F, carbon gets oxidized and Oxygen gets reduced

In g, there is no change in oxidation no of s in both product and Reactants is same +4

Similarly in the case of Ag and Mg.

5 0

2 years ago

A compound is found to contain 73.23% xenon name 26.77% oxygen by mass. What is the empirical formula for this compound ?

Luba_88 [7]

The empirical formula is XeO₃.

Explanation:

Assume 100 g of the compound is present. This changes the percents to grams:

Given mass in g:

Xenon = 73.23 g

Oxygen = 26.77 g

We have to convert it to moles.

Xe = 73.23/ 131.293 = 0.56 moles

O = 26.77/ 16 = 1.67 moles

Divide by the lowest value, seeking the smallest whole-number ratio:

Xe = 0.56/ 0.56 = 1

O = 1.67/ 0.56 = 2.9 ≈3

So the empirical formula is XeO₃.

6 0

3 years ago