imagine-that-you-have-50-mathrmg-of-water-and-50-mathrmg-of-methanol-each-in-a-100-mathrmml-beaker-2

Question

Imagine that you have 50 $\mathrm{g}$ of water and 50 $\mathrm{g}$ of methanol, each in a 100 $\mathrm{mL}$ beaker. You place both on a hot plate on low heat.
a. Which sample will be at a higher temperature after 5 min? Explain your thinking.
b. If the initial temperature of each liquid is $23^{\circ} \mathrm{C},$ what is the temperature of each after 25 cal of energy are transferred from the hot plate to each sample?

David Collins · Accepted Answer

question. Number eight has a couple parts to it, but the scenario is the same for both parts. We have 50 g, methanol and 50 g of water, both placed into separate beakers. Put on a hot plate. Now we need to make an assumption here before we proceed with Part A. We need to assume that the hotplate is transferring the same amount of heat per unit time to both of them. So after five minutes, methanol would have received the same amount of heat as water would have. We can then look at their specific key capacities. One calorie per gram per degree Celsius and 0.58 calories per gram degrees Celsius. Because methanol has a lower specific heat capacity, then it doesn&#x27;t need as much heat to have the same change in temperature or if it receives the same amount of heat. It has a greater change in temperature, so methanol is the one that&#x27;s going to be the warmest After five minutes for Part V. It wants us to calculate the final temperatures for each of them, assuming in the five minutes 25 calories Waas added to both of them. To do that will take. Q is equal to specific heap will do. Water first multiplied by mass multiplied by change in temperature. Final temperature minus initial temperature. The initial temperature was 23. We then get a T final after doing the algebra of 23.5 degrees Celsius. If we do the same thing with methanol having a smaller heat capacity, we should have a higher temperature, which we do of 23.86 or 23.9 degrees Celsius. So is predicted. Methanol with a lower specific heat capacity, has the greatest change in temperature.

Ricajoy Montero · Answer

problem 45 feet or calculating the he change. Good. So before we do with that, let&#x27;s go ahead and just, um, identify. Our scenarios are absorbing. He were releasing heat. Okay, so for a part A and part B, we are Vape rising water. So in order to vaporised returning liquid to gas, So that means we&#x27;re putting in heat to the water molecules. So putting in heat means that water is absorbing heat. Okay. And on the other hand, we are having some condensation for part C in part D. So we&#x27;re turning, um, vapor or gas back into liquid. OK, so what that means for us is, um, your gas is releasing heat. Okay, So moving on to our calculations, we&#x27;re going to need the value for the heat of vaporization of water. Okay, so we got 5 40 calories per gram of water or 2260 jewels. Okay, So, depending on which unit unit we need, um, those are our values. So moving on. Let&#x27;s go ahead and start with part A. Okay. Part a. I got 10.0 grams of water, right, and I&#x27;m Vape rising that I&#x27;m turning into gas and we want it in units of calories. Okay, So what I&#x27;m gonna do here is take this value 5 40 calories per gram of water and multiplying it by 10.0 grams. Okay, so 5 40 calories. Berg, Graham or water, So, as usual, thought unit grams cancels. Okay, so all that&#x27;s left is to do for this part is two point are calculator got in times 5 40 Okay, which of course, is 5400. So we got 5000 400 calories. That&#x27;s it for party. Okay, next port be same thing. But this time we have 5.0 grams, okay? And we wanted in jewels. So that means I&#x27;m using 2260 this time. So I&#x27;m multiplying this by 2260. Jules, Program of water. Okay, so again, you and it&#x27;s cancel and let&#x27;s go ahead and pull out our calculator. We got five times. 2260. Okay, So 11,300. Here&#x27;s her answer. 11,000 300 jewels. Okay, Next the or or import see, party is the opposite. This time we have condensation, but it does not change the way that we solve this problem. OK, so it&#x27;s just a matter of whether it&#x27;s being absorbed or released, but the value is the same. Okay, so eight grams or sorry. 8.0 kilograms this time it 10 kilograms. And, um, as you notice, we have, um, grams in our unit. Okay, so I&#x27;ll go ahead and go on birth. This two grams, 1000 grams is equal to one kilogram. Okay? And we want the answer in cake house. So which means I&#x27;m using this value 5 40 Okay, So, times 5 40 calorie spur graham. But, um, we need to convert this to cake house as well. So one cake out is 1000 calories. OK, so right off the bat, we&#x27;re cancelling the 1000 and the kilograms cancel as well. And the calories unit. So the grams was well gay. So let me clarify that this grams would cancel. Of course, that grams, this unit calories cancels this calories and then the value 1000 cows cancels with this value of 1000 right here. Okay. So real left with cake house spuul out over calculator. I got eight times 5 40 and I think that&#x27;s pretty much it. Yeah. Eight times 5 40 is forced. 4320 we need to significant figures. So that&#x27;s 4300 4300 cake house. Okay, last one parte de resume outs of the gun. More space party. I have 1 75 grams for water, and I want it and killed Jules. Okay, so which means we&#x27;re using this value. So 2 to 60 Jules, spur grams, and then we&#x27;re converting jewels to killer jewels. So one killed Jewel is equals to 1000. Jewell, skip calculator 1 75 times. 2 to 60 divided by 1000 day. So 3 95.5 We need three significant figures, so we&#x27;re rounding it off. 23 96 3 96 kilo joules.

Ricajoy Montero · Answer

problem. 46 were still on calculating he change. Okay, so we have condensation and vaporization. And for that reason, what I have year are the values for heat of vaporization of water Get so let&#x27;s start with identifying whether we are absorbing or releasing heat parts A and B is condensation case who returning gas to liquid. Okay, so when you&#x27;re turning gas to liquid, that means you are taking out heat from gas. Okay, so if you&#x27;re taking out heat, that means that steam is releasing it. Okay. And on the other hand, if you&#x27;re reprising, you&#x27;re turning liquid to gas. That means you&#x27;re putting in heat to water. So that means stop water is absorbing it. So moving on to our calculations, starting with part a. So I&#x27;ll just put it right over here. Part A. I got 10.0 kilograms. Um, water or esteem, actually. And first I need to convert this to Graham&#x27;s case, since our values here used the unit grams, so one 1000 grams is equal to one kilogram. Okay. And next, we are multiplying that, um by 5 40 calories per ground because, um, part is asking for the unit calories OK, so I&#x27;m using 5 40 calories program. So the units would cancel kilogram and kilogrammes and grammes and grams kill. That&#x27;s love. Here is our calculator. I got 10 times 1000 me switch that turns lives 1000 times 5 40 Okay, so we got 5,400,000. We need three significant figures, so that would be 5.40 time stand to the sixth power. I was with a little bit. 5.40 time Stand to the sixth power. Okay, actually, verify that real quick. 36 Okay, so that&#x27;s our answer for party part B port be. I got, um, 7.60 grams of steam and we wanted in jewels. Okay, so that means I&#x27;m using this value. 2260. Square it and multiply that 2260 Jewell spur gram of water or steam. So, grams, cancel out. So plug this into our calculator. They got 7 60 We&#x27;re sorry. 7.60 times. 2 to 60 Okay, 7176. And we need three significant figures. So 224,700. Sorry. 17,200 Jules. Okay. Part C. He got 44 grams of water and we want it in cake house. So I&#x27;m using 5 40 calories. So we multiply that by 5 40 calories per gram and we convert calories to cake out. So one K cow is he goes to 1000 calories. Okay, so I got 44 times 5 40 divided by 1000. Okay, so 23.76 And we need to significant figures. So that gives us 24 24 cake house. Last one party, I got 5.0 kilograms of water. And of course I want to convert that two grams first. Because we need we have grams us our units for heat of vaporization. So 1000 grams is equal to one kilogram. Okay. And next we want it and kill Egil. Some using 2 to 60 jewels per gram water, and we&#x27;re converting jewels to kill. You also want killer Jewell equals 1000 jewels. Okay, so last up here is pulling out that calculator got five. Okay, so let me show you what I&#x27;m doing here. I&#x27;m canceling this 1000. I&#x27;m not gonna put it into the calculator anymore because they have 1000 divided by 1000. Right? And then the grams cancel the kilograms. Cancel. Okay. And the jewels cancel as well. So I&#x27;ve left with killer jewels. Okay, so I got five times. 2 to 60 Okay, so that gives me 11,300. And that&#x27;s pretty much it for this problem. 11,300 kilo jewels.

Averell Hause · Answer

So for party, Um, the energy required to melt two kilograms of ice into liquid water. You could say the energy needed to MT. Would be equaling the mass multiplied by the latent heat of formation for ah h for H 20 So this is gonna give us 2.0 kilograms multiplied by 3.33 times 10 to the fifth Jules per kilogram. And this is giving us 6.66 times 10 to the fifth jewels. So this would be our answer for part a four part B, then the energy remaining toe warm. The water would be the energy remaining toa woman. The water would be the total amount of energy minus the energy required to melt it into water in the first place. So this would be 9.30 minus 6.66 and this would be times 10 to the fifth Jules. And so the energy to warm the water is equaling 2.64 times, 10 to the fifth. Jules, this would be our final answer for Part B. And finally, for part C, we can apply that equation here, Q equaling M C. Delta t Mrs equaling M C. Times the final temperature minus zero degree Celsius so the temperature would be the amount of energy remaining toe warm, the water divided by the mass times of specific heat of water. So this would be 2.64 times 10 to the fifth Jules, and this would be divided by 2.0 kilograms multiplied by 4186 Jules per kilogram period degree Celsius. And this is giving us 31.5 degrees Celsius. So it melts the ice and then one. Once it is melted, it raises the temperature of the water to 31.5 degrees Celsius. That is the end of the solution. Thank you for watching.

Suzanne W. · Answer

a 50 g ice cube, zero degrees Celsius. It is heated until 45 g has become water 100 degrees Celsius and five g has become steam at 100 degrees Celsius. How much energy was added to accomplish the transformation? So first we have melting and then we have heating and then we have vaporization so melting. You get in time else best and then for heating it and see Delta Team. And this is the mass of the vapor. The lane. Okay, so we add all of these together. So notice that the two masses will combine. You have L. F. Plus C delta T plus the mass of the vapor. Oh I see. So substituting what we know, we know all of these latent heat. So LF is going to be 3.3 times 10 to the 5th. He is 41 86. We know adult city is 100 And we know that this latent heat is 2.26 Times 10: six. So solving all of this out and you get an energy of 4.87 times 10 to the 4th in units of jewels.

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Would water make a good thermal insulator for a h…

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