<p>For two bodies of matter in contact, heat always flows from</p>
<p>a. the body with greater heat to the one with less heat
b. the body of higher temperature to the one oflower temperature
c. the denser body to the less dense body
d. the body with more water to the one with less water
e. the larger body to the smaller body</p>
<p>the answer is b.</p>
<p>what is the difference between a and b? I know that heat is the toal amount of kinetic energy in molecules and that temperature is the average amount of kinetic energy. I figured that since temperature X volume equals heat, it would be more accurate to say that heat difference is the bottom line. (who knows that the person with higher temperature is of smaller volume?- for b, I mean)</p>
<p>my school a.p. bio book is pearson, and according to the passage it reads:
"whenever two objects of different temperature are brought together, heat passes from the warmer to the cooler object until the two are the same temperature. Molecules in the cooler object speed up at the expense of the kinetic energy of the warmer object."</p>
<p>When it says “the body with greater heat to the one with less heat” what is really happening is that the body with greater heat(energy) is transferring energy to the one with lower heat(energy) until the temperature is the same. </p>
<p>Having the same temperature does not necessarily equate to having the same heat.</p>
<p>Consider this. If you boil a cup of water and a gallon of water, both will boil at the same temperature but the gallon of water will still produce more heat because more molecules are generating energy than in the cup of water. </p>
<p>In English speech we use heat and temperature the same way but they mean different things in reality.</p>
<p>Heat is essentially energy.
Temperature is only a measure of it.</p>
<p>This is why b is correct. The energy will transfer from the object with higher temperature to the one with lower temperature until the temperatures are equal regardless of whether they produce equal heat.</p>
<p>ETA: </p>
<p>The amount of heat needed to heat a subject from one temperature level to an other can be expressed as: Q = cp * m * dT where:</p>
<p>Q = amount of heat (kJ)
cp = specific heat (kJ/kgK) - (4.19 kJ/kg K) <- Specific heat of water
m = mass (kg)
dT = temperature difference between hot and cold side (K)</p>
<p>Heating 1.0 kg of water from 0 - 100 Celsius
Q = (4.19 kJ/kg.K) (1.0 kg) ((100 oC) - (0 oC))</p>
<pre><code>= 419 (kJ)
</code></pre>
<p>Heating 10.0 kg of water from 0 - 100 Celsius
Q = (4.19 kJ/kg.K) (10.0 kg) ((100 oC) - (0 oC))</p>
<pre><code>= 4190 (kJ)
</code></pre>
<p>** 100 C and 419kJ vs 100 C and 4190kJ. Same temperature but different heat.** These to amounts of water won’t transfer energy because the temperatures are the same despite the heat difference.</p>
<p>Energy will only transfer to an object with lower heat (kinetic energy) until the temperature (measure of heat) is the same.</p>
<p>If you use answer (a) then the energy will transfer until the heat balances out. This will result in the 10 kg of water being 100 Celsius and 4190 kJ but then 1 kg has to raise to 1000 Celsius to maintain the same heat of 4190 kJ. Does this happen in real life? No.</p>
<p>This is why (b) is the answer. When you watch the two waters the 1 kg will raise to the same temperature as the 10 kg and then stay at 100 (actually one will raise and the other will lower a little but that is not important in this instance).</p>
<p>The formulas shows that 10 times the amount of water has 10 times the amount of heat but equal temperatures. The real world shows us that 2 objects of different temperatures equalize temperatures (when you put ice in hot water the temperatures equalizes to one temperature).</p>
<p>So “b. the body of higher temperature to the one oflower temperature” is the right answer.</p>
<p>Hey, this is really random, but do u guys know how to name the carbons in a carbon right structure? My teacher was talking about it like carbon number 1 but I can’t tell which is the first one</p>
<p>@xSlakcer,
thank you so much; so what u’r saying basically is that it is hard for a mass of greater heat to equalize its heat content with another mass of lower heat, right? (while it is feasible for this mass of greater heat to equalize its temperature with the other one with lower heat content)</p>
<p>@warlands719,
I think your teacher is referring to the carbon number 12, which is the most commonly found carbon type in nature… Carbon 12 is the usual carbon that has 12 neutrons. I guess ur teacher was trying to distinguish it from carbon 13, and carbon 14, which are two isotopes of carbon 12.
Or maybe, your teacher was referring to molecules that have only one carbon. I dunno.
(I don’t really get what you mean by “carbons in carbon right structure”)</p>
<p>Another analogy my Bio teacher used was swimming in the ocean. The ocean’s temp is probably 60 degrees and your body is about 98.6. The ocean has a lower temperature than your body. However ocean has more heat because if you add up the speeds of all the molecules in water, it would be a LOT more than if you added up all the speeds of the molecules in your body. If a. were to be true, the ocean would get colder as it tries to dump all it’s heat into your body and you would get warmer as you would try to gain all of the oceans heat. </p>
<p>I think that’s another way to look at it. That’s what I got out of it, haha.</p>
<p>Carbons in organic structures are numbered for clarity. Generally, it’s numbered in such a way so that the lowest numbers are used to describe the figure (so it’s 1-propanol instead of 3-propanol), but there’s a hint of tradition to it as well. For example, sugars start at the end closest to the C=O group, and if they’re part of a nucleotide, they get the “prime” mark after the number to distinguish them from the nucleotide’s atoms. (so 1->1’, etc.)</p>
<p>What type of molecule was she talking about?</p>
<p>(oh, and next time - start your own thread, please. That keeps things nice and orderly)</p>
<p>
</p>
<p>I’m pretty sure that actually refers to chirality. Some organic molecules come in two forms, a D- form and an L-form, that are mirror images of each other. As the D- and the L- refer to the Latin words for “right” and “left” and that pairs of chiral molecules are also referred to as “right-handed” and “left-handed”, that could be it.</p>