الجواب هو الأول الجواب هو الأول
<span>D. sugar changes from white to a light amber color
We're looking for a chemical change. So let's examine the options and see what happening with them.
A. adding cream and milk to the mixture
She's just making a mixture here. No unexpected reactions or changes happen as she adds the cream and milk. So this is the wrong answer.
B. mixing the sugar with water
Dissolving the sugar in water. Once again, nothing unusual happens and if she were to evaporate the water, she'd be left with the original sugar. So this is the wrong answer.
C. melting the sugar
Just starting a simple phase change. Once again, no the right answer.
D. sugar changes from white to a light amber color
She's melted the sugar and has a clear fluid. As she continued to heat this fluid, it suddenly turns light amber. She has made a permanent change to the substance that she can't undo by simply physical means. She has converted part of the sugar into caramel. So a chemical change has happened here.</span>
Answer:
= 285 Joules
Explanation:
a) answer can be found out in attachment
(b) The temperature for the isothermal compression is the same as the temp at the end of the isobaric expansion. Since pressure is held constant but volume doubles, we use the ideal gas law:
p V = nR T to see that the temperature also doubles.
.So... temp for isothermal compression = 355×2 = 710 K
.(c) The max pressure occurs at the top point. At this point, the volume is back to the original value but the temperature is twice the original value. So the pressure at this point is twice the original, or
max pressure = 2×240000 Pa = 480000 Pa = 4.80 x 10^5 Pa
(d) total work done by the piston = workdone during isothermal compression - work done during expansion =
= nRT ln(V initial / V final)-p (V initial - V final)
= nRT ln(2) - nR(T final - T initial)
= 0.250× 8.314 ×710×ln(2)-0.250×8.314× (710 - 355)
= 285 Joules
1.) B.
2.) A.
3.) A.
If these are wrong please delete.
Thank You!
<3
I know that the water vapor is the gaseous phase of water. But what is the dew? I just wonder how can I categorized it. Is it the liquid or the gas phase of the water.
Figure below shows dew formed in grass. It seems as a liquid. But is it actually exhibit in liquid phase or gas phase?The answer is water vapor
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