Heats Sentence Examples

The accuracy of heats of combustion determined in the closed calorimeter is in favourable cases about one-half per cent.

With knowledge then of the heats of formation of the substances involved in any chemical action, we can at once calculate the thermal effect of the action, by placing for each compound in the energy-equation its heat of formation with the sign reversed, i.e.

Thus if we wish to ascertain the thermal effect of the action Mg+CaO =MgO+Ca, we may write, knowing the heats of formation of CaO and Mg0 to be 131000 and 146000 respectively, 0-131000 = 0-146000+x x =15000 cal.

Since heats of formation afford such convenient data for calculation on the above method, they have been ascertained for as many compounds as possible.

Now we know the heats of formation of carbon dioxide (from diamond) and of liquid water to be 94300 cal.

The oxygen contained in the compound was deducted, together with the equivalent amount of hydrogen, and the heat of combustion of the compound was then taken to be equal to the heats of combustion of the elements in the residue.

It has already been stated that the heats of neutralization of acids and bases in aqueous solution are additively composed of two terms, one being constant for a given base, the other constant for a given acid.

The intricate water-ways and the stubborn Venetian defence baffled all his attempts to reach Rialto; the summer heats came on; the Lido was unhealthy.

Thomsen then investigated heats of combustion of various benzenoid hydrocarbons - benzene, naphthalene, anthracene, phenanthrene, &c. - in the crystallized state.

Specific Heat and Composition.-The nature and experimental determination of specific heats are discussed in the article Calorimetry; here will be discussed the relations existing between the heat capacities of elements and compounds.

The following table gives a comparative view of the specific heats and the ratio for molecules of variable atomic content.

For a further discussion of the ratio of the specific heats see Molecule.

Dulong to investigate relations (if any) existing between specific heats and the atomic weight.

This law-purely empirical in origin-was strengthened by Berzelius, who redetermined many specific heats, and applied the law to determine the true atomic weight from the equivalent weight.

At the same time he perceived that specific heats varied with temperature and also with allotropes, e.g.

Nilson and Pettersson's observations on beryllium and germanium have shown that the atomic heats of these metals increase with rise of temperature, finally becoming constant with a value 5.6.

Other metals were tested in order to determine if their atomic heats approximated to this value at low temperatures, but with negative results.

We now proceed to discuss molecular heats of compounds, that is, the product of the molecular weight into the specific heat.

The specific heat of a compound may, in general, be calculated from the specific heats of its constituent elements.

Conversely, if the specific heats of a compound and its constituent elements, except one, be known, then the unknown atomic heat is readily deducible.

Similarly, by taking the difference of the molecular heats of compounds differing by one constituent, the molecular (or atomic) heat of this constituent is directly obtained.

The equivalent weight is capable of fairly ready determination, but the settlement of the second factor is somewhat more complex, and in this direction the law of atomic heats is of service.

The specific heat of indium is o 057; and the atomic heats corresponding to the atomic weights 38, 76 and 114 are 3.2, 4.3, 6.5.

In the article Thermo Chemistry a general account of heats of formation of chemical compounds is given, and it is there shown that this constant measures the stability of the compound.

The researches of Julius Thomsen and others have shown that in many cases definite conclusions regarding constitution can be drawn from quantitative measurements of the heats of combustion; and in this article a summary of the chief results will be given.

The identity of the four valencies of the carbon atom follows from the fact that the heats of combustion of methane, ethane, propane, trimethyl methane, and tetramethyl methane, have a constant difference in the order given, viz.

It therefore appears that the difference between the heats of combustion of two adjacent members of a series of homologous compounds is practically a constant, and that this constant has two average values, viz.

An important connexion between heats of combustion and constitution is found in the investigation of the effect of single, double and triple carbon linkages on the thermochemical constants.

It contains four independent constants; two of these may be calculated from the heats of combustion of saturated hydrocarbons, and the other two from the combustion of hydrocarbons containing double and triple linkages.

It is remarkable that the difference in the heats of formation of ketones and the paraffin containing one carbon atom less is 67.94 calories, which is the heat of formation of carbon monoxide at constant volume.

It is remarkable that the position of the halogen in the molecule has no effect on the heat of formation; for example, chlorpropylene and allylchloride, and also ethylene dichloride and ethylidene dichloride, have equal heats of formation.

On the plains rain rarely falls during the heats of summer; and the showers though violent are generally of short duration, whilst the moisture is quickly evaporated owing to the aridity of the atmosphere.

To test the purity of the metal the tin-smelter heats the bars to a certain temperature just below the fusing point, and then strikes them with a hammer or lets them fall on a stone floor from a given height.

The blower repeatedly heats the lower part of the mass of glass and keeps it distended by blowing while he swings it over a deep trench which is provided next to his working platform.

The blower then heats the end of the cylinder again and rapidly spins the pipe about its axis; the centrifugal effect is sufficient to spread the soft glass at the end to a radius equal to that of the rest of the cylinder.

Thermal Properties.-The specific heats of most metals have been determined.

The general result is that, conformably with Dulong and Petit's law, the "atomic heats" all come to very nearly the same value (of about 6.4); i.e.

Latent Heats of Liquefaction.-Of these we know little.

In the course of his inquiries he also noticed that different bodies in equal masses require different amounts of heat to raise them to the same temperature, and so founded the doctrine of specific heats; he also showed that equal additions or abstractions of heat produced equal variations of bulk in the liquid of his thermometers.

He also showed that the difference of the specific heats at constant pressure and volume, S - s, must be the same for equal volumes of all gases at the same temperature and pressure, being represented by the expression R/TF'(t).

He remarks that ” the law according to which the motive power of heat varies at different points of the thermometric scale is intimately connected with that of the variations of the specific heats of gases at different temperatures - a law which experiment has not yet made known to us with sufficient exactness."

The same equations apply to the case of fusion of a solid, if L is the latest heat of fusion, and v', s', v", s" the specific volumes and specific heats of the solid and liquid respectively.

Since h = s (o' - 0"), the difference S - s between the specific heats at constant pressure and volume is evidently H/(o' - o").

The isothermal elasticity - v(dp/dv) is equal to the pressure p. The adiabatic elasticity is equal to y p, where -y is the ratio S/s of the specific heats.

The specific heats are independent of the pressure or density by equations (to) and (12).

In thiscase the ratio of the specific heats is constant as well as the difference, and the adiabatic equation takes the simple form, pv v = constant, which is at once obtained by integrating the equation for the adiabatic elasticity, - v(dp/dv) =yp.

The specific heats may be any function of the temperature consistently with the characteristic equation provided that their difference is constant.

We may therefore reasonably assume that the limiting values of the specific heats at zero pressure do not vary with the temperature, provided that the molecule is stable and there is no dissociation.

The expression for the change of intrinsic energy E between any given limits poOo to po is readily found by substituting these values of the specific heats in equations (II) or (13), and integrating between the given limits.

This means that sea-water heats and cools somewhat more readily than pure water.

Comparing the velocities of sound U i and U2 in two different gases with densities and at the same temperature and pressure, and with ratios of specific heats 'yl, 72, theory gives Ui/U2 = 1/ {71 p 2/72 p i }.

Kundt's dust-tube may also be employed for the determination of the ratio of the specific heats of a gas or vapour.

If U is the velocity of sound in a gas at pressure P with density p, and if waves of length X and frequency N are propagated through it, then the distanc?e l between the dust-heaps is 2 = N - zN Vyp' where y is the ratio of the two specific heats.

The latent heat L at any temperature is given by L=Lo - f 0 64 0 (s - s')dT, where Lo is value at To and s--s' is the difference in the specific heats of water and ice.

The most remarkable physical property of argon relates to the constant known as the ratio of specific heats.

The ratio of specific heats of the principal gases is I.

If, as for Boscovitch points, the whole energy is translatory, the ratio of specific heats must be I.

These gases agree with argon in respect of the ratio of the specific heats and in being non-oxidizable under the electric spark.

He published many physical memoirs on electricity, the dilatation of liquids by heat, specific heats, capillary attraction, atomic volumes &c. as well as a treatise in 4 volumes on Fisica di corpi ponderabili (1837-1841).

In it the steel heats the converter, whereas in the open-hearth and crucible processes the furnace heats the steel.

The two carried out some of the earliest thermochemical investigations, devised apparatus for measuring linear and cubical expansions, and employed a modification of Joseph Black's ice calorimeter in a series of determinations of specific heats.

Regnault executed a careful redetermination of the specific heats of all the elements obtainable, and of many compounds - solids, liquids and gases.

This is a very good method of comparing the mean specific heats over two ranges of temperature such as 0-50, and 50-100, or 0-20 and 20-40, but it is not so suitable as the electric method described below for obtaining the actual specific heat at any point of the range.

These methods have reached their highest development in connexion with the determination of the mechanical equivalent of heat, but they may be applied with great advantage in connexion with other problems, such as the measurement of the variation of specific heat, or of latent heats of fusion or vaporization.

But For The Determination Of Relative Values Of Specific Heats In Terms Of A Standard Liquid, Or Of The Variations Of Specific Heat Of A Liquid, The Method Depends Only On The Constancy Of The Standards, Which Can Be Readily And Accurately Tested.

The Most Important Cases Are, The Specific Heats (I) At Constant Volume; (2) At Constant Pressure; (3) At Saturation Pressure In The Case Of A Liquid Or Vapour.

Thus The Direct Experimental Evidence Is Somewhat Meagre And Conflicting, But The Question Of The Relation Of The Specific Heats Of Gases Is One Of Great Interest In Connexion With The Kinetic Theory And The Constitution Of The Molecule.

The Expansion Per Degree At Constant Pressure Is V/9 = R/P. The External Work Of Expansion Per Degree Is Equal To R, Being The Product Of The Pressure And The Expansion, And Represents The Difference Of The Specific Heats S S, At Constant Pressure And Volume, Assuming As Above That The Internal Work Of Expansion Is Negligible.

If The Molecules Are Supposed To Be Like Smooth, Hard, Elastic Spheres, Incapable Of Receiving Any Other Kind Of Energy Except That Of Translation, The Specific Heat At Constant Volume Would Be The Increase Per Degree Of The Kinetic Energy Namely 3Pv/20=3R/2, That At Constant Pressure Would Be 5R/2, And The Ratio Of The Specific Heats Would Be 5/3 Or 1.666.

Considering The Wide Variations In The Physical Condition And Melting Points, The Comparatively Close Agreement Of The Atomic Heats Of The Metals At Ordinary Temperatures, Known As Dulong And Petit'S Law, Is Very Remarkable.

No Doubt There Must Be Approximate Relations Between The Atomic And Molecular Heats Of Similar Elements And Compounds, But Considering The Great Variations Of Specific Heat With Temperature And Physical State, In Alloys, Mixtures Or Solutions, And In Allotropic Or Other Modifications, It Would Be Idle To Expect That The Specific Heat Of A Compound Could Be Accurately Deduced By Any Simple Additive Process From That Of Its Constituents.

It was applied in the most perfect manner by Regnault to determine the latent heats of steam and several other vapours at high pressures.

The first accurate calculations of the specific heats of air and gases were made by Rankine in a continuation of the paper already quoted.

Employing Joule's value of the mechanical equivalent of heat, then recently published, in connexion with the value of the ratio of the specific heats of air S/s=I.

Adopting for steam the same value of the ratio of the specific heats, viz.

We have therefore the simple relation between the total heats at A and D H A -H D =S (0"--0).

A formula of this type has been widely employed by van't Hoff and others to calculate heats of reaction and solution from observations of solubility and vice versa.

He proceeds to calculate from this expression the difference of vapour-pressures of ice and water in the immediate neighbourhood of the melting-point, but does not observe that the vapour-pressures themselves may be more accurately calculated for a considerable interval of temperature by means of formula (23), by substituting the appropriate values of the latent heats and specific heats.

Taking for ice and water the following numerical data, L = 674.7, 6 74.7, L 1 =595.2, L r = 79.5, R = o 11 03 cal./deg., po = 4.61 mm., s-S = 519 cal./deg., and assuming the specific heat of ice to be equal to that of steam at constant pressure (which is sufficiently approximate, since the term involving the difference of the specific heats is very small), we obtain the following numerical formulae, by substitution in (23), Ice..

It is generally called Dupre's formula in continental text-books, but he did not give the values of the coefficients in terms of the difference of specific heats of the liquid and vapour.

In a third, " On some important points in the theory of heat " (1819), they stated that the specific heats of thirteen solid elements which they had investigated were nearly proportional to their atomic weights - a fact otherwise expressed in the " law of Dulong and Petit " that the atoms of simple substances have equal capacities for heat.

Subsequent papers by Dulong were concerned with " New determinations of the proportions of water and the density of certain elastic fluids " (1820, with Berzelius); the property possessed by certain metals of facilitating the combination of gases (1823 with Thenard); the refracting powers of gases (1826); and the specific heats of gases (1829).

When it is roasted and rolled to his satisfaction he gently heats the centre of the bowl, where there is a small orifice; then he quickly thrusts the end of the dipper into the orifice, twirls it round smartly and withdraws it; if this is properly done, the opium (now about the size of a grain of hemp-seed or a little larger) is left adhering to the bowl immediately over the orifice.

Extremes of temperature are not so great as farther inland in the same latitude; for the summer heats are tempered by the sea and the cool north winds, and the winter cold is so constant as to be less severely felt than the changing temperature of more southern districts.

Extremes of heat and cold occur, but as a rule the winters are dry and mild, while the summer heats are tempered by the perpetual prairie breezes, and the summer nights are usually cool and refreshing.

Coke or anthracite is heated to incandescence by an air blast in a generator lined with fire-brick, and the heated products of combustion as they leave the generator and enter the superheaters are supplied with more air, which causes the combustion of carbon monoxide present in the producer gas and heats up the fire-brick baffles with which the superheater is filled.

The sheltered bays near Fiume enjoy an equable climate; but in all other districts the temperature in mid-winter falls regularly below zero, and the summer heats are excessive.

As the boiler burns biogas, a proportion of its output would be converted to electricity, while the rest heats the home.

In 1911 he constructed a special calorimeter that measured specific heats at very low temperatures.

The heats of the women's 200 meters freestyle had the feel of a final for two reasons.

The radiant heat which is produced heats only surfaces which it falls on and is relatively unaffected by air movement.

Sienna tipped as Oscar race hots up It seems Sienna Miller is the actress everyone's talking about as the Oscar race heats up.

And seized an including karaoke and heats up on grand ballroom can.

Its dry, warming energy is highly compatible with the human body and it heats the tissues deeply, stimulating lymph and blood flow.

Heating - The Kitchen is heated by a Multifuel stove, which also heats the water.

It absorbs solar ultraviolet radiation, which heats the stratosphere.

Its ratio of specific heats has very nearly the ideal value 1 666, appropriate to a monatomic molecule.

Joule afterwards proved (see below) that Mayer's assumption was in accordance with fact, so that his method was a sound one as far as experiment was concerned; and it was only on account of the values of the specific heats of air at constant pressure and at constant volume employed by him being very inexact that the value of the mechanical equivalent of heat obtained by Mayer was very far from the truth.

Substances with positive heats of formation are termed exothermic; those with negative heats of formation are termed endothermic. The latter, which are not very numerous, give out heat on decomposition into their elements, and are more or less unstable.

It is now known, however, that when weak acids or bases are used, the heat of neutralization may be either greater or less than the normal value for powerful acids and bases, so that there is no proportionality, or even parallelism, between the strengths of acids and their heats of neutralization (see Solutions).

The abnormal specific heats of the halogen elements may be due to a loosening of the atoms, a preliminary to the dissociation into monatomic molecules which occurs at high temperatures.

The bottle maker heats the fractured neck of the bottle, binds a band of molten glass round the end of it and simultaneously shapes the inside and the outside of the neck by using the tool shown in fig.

This energy, therefore, comes under a different category from the energy for which the law of equipartition was proved, for in proving this law conservation of ' Very significant confirmation of this conjecture is obtained from a study of the specific heats of the elements in the solid state.

Pick's system a triple effect is obtained by evaporating in these connected vessels, so that the steam from one heats the second into which it is led (see Soc. of Eng., 1891, p. 115).

His great experimental discovery, known as the "Peltier effect," was that if a current pass from an external source through a circuit of two metals it cools the junction through which it passes in the same direction as the thermo-electric current which would be caused by directly heating that junction, while it heats the other junction (see Thermo-Electricity), Peltier died in Paris on the 27th of October 1845.

Every day the earth heats and cools as night turns into day and back into night.

Plus, they will be able to convert heat to electricity as well, so anything that heats up will become an energy source.

The splitting of these atoms gives off large amounts of heat energy which heats a gas used to cool the fuel rods.

Pump makes a loud squealing noise, it heats up or is not running to its full capability.

It was wonderful to watch him try tho and made a nice change from the normal heats which can be pretty boring.

The new air conditioner heats the home very efficiently, allowing us to spend less money on bills.

Click the control once and the inner ring heats up for small pots or click it twice for the entire burner to heat up to accommodate a larger one.

Finally, there are stainless steel cookware sets, which are easy to clean but are also prone to hot spots, where one area of the pan bottom heats hotter than others.

This is different to central heating that heats an entire house and gives background heat.

While, of course, central heating can also be described as heating space (and indeed it could be argued that every heater heats space of some description), the term 'space heater' is used to describe this particular form of heater.

This might mean that the heater over heats a room or needs to be constantly run on a high setting because it is not powerful enough.

The site claims that the pan heats evenly so all of your muffins turn out the same.

Propane typically heats water for 50% less cost than electricity.

Central heating is the term used to describe the heating of a whole house and a space heater is the term used to describe a heating device that heats a smaller space.

It also creates electricity by powering generators and it heats homes and commercial buildings.

Unlike traditional water heaters, that use an immersion heater to heat a tank of water regardless of how much is required, a tankless system heats just the water required.

These thermal collectors circulate water through a space, which in turn, heats the air in that specific area.

When a room heats up from the sunlight streaming through a south facing window, it is being heated by passive solar energy.

A wok is bowl shaped and great for cooking at high heats.

As the oven heats and the butter melts, put the eggs in a food processor or a blender and blend for one minute.

While the skillet heats, rub the tenderloin with salt and pepper.

Heats, flowers, swirls, and stars look great covered with fuzzy flocking.

The technician simply heats the shell, you step into the shell and the shell moulds and forms to the metatarsal contour of your foot.

In preparing for a hot stone massage, the therapist heats smooth black basalt stones in water heated to 120-150 degrees Fahrenheit.

Pasteurization heats foods to a temperature unacceptable to raw food diet followers.

Pasteurization heats nutritional yeast beyond the temperature of 116-118 degrees Fahrenheit, thus pushing it out of the raw food category.

Finally, let talk about "white, or silent heats".

I have found some gain from late sowing in July, the May-sown plants dying off in the August heats.

During the heats of summer it requires frequent watering, and at the approach of winter it should be moved to the greenhouse, except in mild districts.

Once the gas is ignited, the firebox draws in the cold air from the surrounding room and heats it.

The same forced hot water that heats your old clanking radiator can be redirected into a new system that is far more efficient and cheaper to run.

A tankless water heater fueled by propane heats water by circulating it through a series of burners.

When the weather heats up again, you may find that you need to purchase some new big men's summer clothing.

If you're up early and plan to be out for a while, you may want to throw on an extra layer over your summer clothing before it heats up in the afternoon or after it cools back off in the evening.

Made from pretty, lightweight fabrics with figure flattering silhouettes, junior plus size summer dresses can be fun, flirty and extremely practical as summer heats up.

When the weather heats up you can count on finding a great selection in sizes and cuts designed to fit and flatter the plus figure.

In chaos field, the action heats up considerably.

When you first start the game, you only have access to the first two levels of the heats.

Vintage Valentine Art Collections from The Stock Solutions provides dozens of Victorian images featuring floral designs, heats, couples, children and romance.

The unit features an oven that heats to 400 degrees and fully functional non-stick stove burners.

Put the saucepan over a medium heat and, as the steam heats the cream/chocolate mixture, use your whisk to blend the chocolate and cream until it is a smooth blend.

Think of it as a low-powered hair dryer in the shape of a barrel that heats your hair up from the inside rather than from on top.

Others opt for a closely-shorn cut when the weather heats up.

Evaporation occurs when the sun heats water in lakes or oceans and turns it into steam.

Watch with your child as the water heats up and produces steam.

If the group is large, you can have head to head heats, with each winner advancing to the next level of the contest.

Aluminum heats up under quickly and sometimes the framework begins to bend under weight.

The downside to this material is that it heats up quickly in the sun and can burn your backside if you're not careful.

There's enough water between the suit and the skin so that the wearer's body heats it up and preserves additional heat that may otherwise escape under the water.

When the temperature heats up, you want clothing that holds up to the summer sun, whether you're at work or at play.

Whether you prefer to show off just a hint of skin or plenty of it, you can count on making quite an impression when the weather heats up.

In cases of heating elements in modern times, a trigger or timer activates the element which quickly heats up to disperse the heat around whatever object needs cooked or heated.

The microwave is a great invention, since it heats and cooks food in minutes and knowing how to repair a microwave when you're in dire need will help with easy issues that arise.

The advantage to owning an electric griddle over a regular one that heats on the stove is the uniformity in heating.

The griddle plugs into an outlet and heats the grill more consistently than burners on a stove top.

For example, the DynaGlo Pro is a portable propane heater that is done in a convection design that heats up smaller spaces such as workshops.

Because this kind of heater has a large surface area, it heats a room quickly, evenly and efficiently.

The heat produced by this type of heater travels through the humidity of the room so it heats gently without drying the air out.

Fill only to the indicator line because as it heats up, kerosene expands and if overfilled, the liquid could spill out and result in a fast spreading fire.

The appliance automatically heats to the perfect temperature for frying.

Humidifiers have a water storage tank that heats to produce steam or cools to produce a fine mist.

Convection heaters have a liquid inside, typically oil, which heats up when the device is on and transfers heat.

It glides effortlessly over fabric and heats quickly and consistently.

Induction cooktop technology heats only the pan and its contents and offers energy efficiency by reducing wasted heat when compared to radiant and gas cooktops.

And because the induction heats only the cookware and its contents, spills won’t bake onto the cooktop, making it very easy to clean.

The modeling wax is easy to shape and mold as it heats up from the warmth of your hands.

You'll love it when the weather heats up - it pairs perfectly with summery ensembles.

It's sure to be a favorite as the weather heats up thanks to its fresh, summery look.

Most rooms in your home have an opening on the wall near the ceiling or floor where the filtered air cools or heats the room.

It's not truly a cold process, because the fat has to be heated, and when you add water to lye it heats up as well.

Cayenne pepper has thermagenic properties and heats up your body.

Your body heats up by burning more fuel, or calories.

You will never find a cooking pan that heats as evenly as a cast iron skillet or prevents sticking assuming the pan has been taken care of and seasoned correctly.

Nothing heats up an already fun evening like some fantasy lingerie.

In season four, Dean is resurrected from hell by an angel as Christian mythology and the war between heaven and hell heats up.

Sadly, these unwelcome pests come out in droves when the weather heats up.

The winds are liable to little variation; they blow from the west, often with great violence, for nine months in the year, and at other times from the north; and they moderate the summer heats, which are chiefly felt during the months of July and August, when the hot winds blow from the coast of Anatolia.

The extreme frosts and heats of the English climate are unknown, but occasional heavy snow-falls occur, and the sea in shallow inlets is covered with a thin coating of ice.

He therefore abstained from determining for each case the specific heats of the solutions he employed, and contented himself with the above approximation.