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20 votes

Why does temperature not increase by putting more logs into the fire

Adding more fuel doesn't permit an arbitrarily high combustion temperature because of an unavoidable intrinsic limitation: The reaction has to heat its products. (In the case of wood, this is mostly ...
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9 votes

Why does temperature not increase by putting more logs into the fire

I agree with Chemodynamics, and I will try to add a different perspective (or maybe two). The fire process is a process where you add a fuel (i.e. energy in the system), and that fuel is gradually ...
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6 votes
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Difference between temperature and heat

In engineering terms heat (energy) and temperature are two different things. One (of many) real life examples is the kitchen stove. When you turn on the kitchen, (and leave it at a set point), the ...
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5 votes
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Why is the carrier block in a winchester rifle made of brass?

Brass is a natural choice for accomodating sliding or rotating contact with steel surfaces. This is because oxide grit or metal particles which would cause galling get embedded into the (softer) brass ...
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5 votes
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In case of solvation , Who converts gaseous ions to aqueous ? Why do we even have gaseous but not solid ions?

We define reactions uniquely depending on the reactants and products. Here are examples related to your question. Formation: Na(s) + (1/2)Cl$_2$(g) $\rightarrow$ NaCl(s) Lattice Formation: Na$^+$(g) + ...
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5 votes

Difference between temperature and heat

A little example: Water has a specific heat capacity (SHC) of 4.2 kJ.kg-1.K-1. I have a 2.1 kW electric kettle. $$ \Delta T = \frac {P \cdot t}{m \cdot SHC} $$ where $ \Delta T $ is the temperature ...
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4 votes

Why does temperature not increase by putting more logs into the fire

I think a review of the definition of specific heat will help: Specific heat is the amount of energy required to raise one gram of a pure substance by one degree Centigrade. $C_P = \frac {Q}{m\Delta T}...
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4 votes
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Damage to drill through torque?

The very first thing to check is the sharpness of the bit tip. a dull bit will not drill worth a d*mn and just waste your battery power. Note that it only takes one brief encounter with something hard ...
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3 votes
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Temporary spray adhesive to hold two plates together for drilling?

Yes, it would be a nightmare to separate. That adhesive is designed for high strength, temperature resistant applications. That max temp is the point at which it looses it's rated strength. It may ...
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3 votes

Temporary spray adhesive to hold two plates together for drilling?

Two flat metal plates can be stuck together just by a thin layer of grease. Then work to be drilled needs clamping anyway.
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3 votes
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Does it make sense to increase the thermal "dead weight" of a wood stove?

Several high performance houses with lots of insulation have been designed with wood stoves that are surrounded by lots of stone to give the thermal mass. Some are still giving out heat 24 hours after ...
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3 votes

Why does thermal conductivity of a pipe matter in a double pipe heat exchanger?

In the steady-state case you describe, the thermal conductivity determines how much heat (kW) a material will trasnmit per unit surface for a given temperature difference (K). In heat exchanger ...
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2 votes

Difference between temperature and heat

Temperature is an intensity , heat is a quantity.
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2 votes

What can you coat/seal Gallium with?

It's unlikely that you'll be able to find a coating of any sort that insulates the item from thermal changes as a result of holding it. How does one prevent an element from melting at 85 °F? Enclose ...
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2 votes

Can I weld a copper pipe into a CPU heat sink for better cooling?

I think, it is necessary to find a cause of overheat. This may be due to bad thermal contact somewhere: between integrated circuit and metal pad through thermal paste or pad between metal pad and ...
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1 vote
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Can I weld a copper pipe into a CPU heat sink for better cooling?

If the existing heatsink is made of copper, then yes you can solder more copper onto it and it will probably dissipate more heat. You can probably weld copper, but it's not commonly done. If the ...
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1 vote
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What can you coat/seal Gallium with?

What you're asking for is a perfect insulator. There is no perfect insulator, let alone a thin film liquid kind. If ambient temperature is even on iota higher than the melting temperature, eventually ...
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1 vote

Does it make sense to increase the thermal "dead weight" of a wood stove?

Sounds right. The more passive thermal mass you have, the larger heat reservoir you have, and the more smooth the temperature VS time curve will be. It's like having a large flywheel on an engine. ...
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1 vote

Calculating Indoor temperature of a structure

There are a few things that IMHO are issues in this problem: I don't see any physical reasoning behind the main equation you are using. Since this is about a transient problem (i.e. how does the ...
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1 vote

Minimizing home heating costs

A suspended ceiling at a height of 2.4m is the most efficient way of saving the heating cost. Because right now most of the heat in your home goes up to the high ceiling. If you don't have access to ...
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1 vote
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Why does thermal conductivity of a pipe matter in a double pipe heat exchanger?

Example Since the rest of the answer is too long I will start with an example. Imagine you could build a heat exchanger from wooden pipes. If you run through the liquid you would observe very little ...
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1 vote

Why does thermal conductivity of a pipe matter in a double pipe heat exchanger?

I didn't realize how confusing the terms could be for a heat exchanger until I started typing it out: I will refer to the hot side as: the side where fluid leaves cooler than it enters the side that ...
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1 vote
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What does it mean by average kinetic energy of molecules as temperature?

IMHO you are still confusing heat with temperature (despite the answer to this question or this ). My Q is why does increased motion or mass of molecules contribute to heat , increased temperature. ...
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1 vote
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Difficulty in understand the meaning of standard enthalpy of formation

I prefer this definition for Hf: "The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its ...
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1 vote
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Can I consider this scenario for the phase change of $H_2O_{(s)}$ to $H_2O_{(L)}$

Figure 1. The phase diagram for water. The pressure and temperature axes on this phase diagram of water are not drawn to constant scale in order to illustrate several important properties. Image ...
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1 vote

Difference between temperature and heat

Keep adding heat to water when it is at 100 deg C causes a phase change but no more temperature change.
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1 vote

What is heat , chemical energy and thermodynamics laws restrictions

Our categorization systems and atomic models are all an approximation, but they help relate the things we can't see to things we can visualize and understand. We define a chemical reaction as one ...
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1 vote

Why does temperature not increase by putting more logs into the fire

Adding more wood does not change the temperature at which wood burns, but it does give you more heat. Think of it this way: a 15,000 BTU furnace may heat a small apartment, but you'll need a 100,000 ...
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1 vote

Difficulty in understanding the scenario for this Q

At the instantaneous moment of stopping the Container, there will be a rush of the molecules of the rear end to the front end. After some time, $\delta t$ this rush will cause extra pressure on the ...
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1 vote

Difficulty in understanding the scenario for this Q

One basic notion behind this is that temperature of a substance is defined as the average kinetic energy of all the atoms or molecules of that substance. Now assume gas in a balloon. Also assume that ...
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