To calculate the amount of heat released in a chemical reaction, use the equation Q = mc ΔT, where Q is the heat energy transferred (in joules), m is the mass of the liquid being heated (in kilograms), c is the specific heat capacity of the liquid (joule per kilogram degrees Celsius), and ΔT is the change in …

Calorimeter, device for measuring the heat developed during a mechanical, electrical, or chemical reaction, and for calculating the heat capacity of materials. Calorimeters have been designed in great variety.

The calorimeter traps all the heat from a chemical reaction, we measure the effect of that heat on the temperature of water in the calorimeter, and we can then calculate the heat energy released by the reaction. The calorimeter is an insulated container, in which we place a measured mass of water.

As a form of energy, heat has the unit joule (J) in the International System of Units (SI). However, in many applied fields in engineering the British thermal unit (BTU) and the calorie are often used. The standard unit for the rate of heat transferred is the watt (W), defined as one joule per second.

Well, so as to prevent hot-spots, and burning on the bottom of the pan. When you do a calorimetric experiment, you have a given mass of water, and you want the temperature rise of this mass to be uniform. So you stir it.

The specific heat capacity of water is 4.18 J/g/°C. We wish to determine the value of Q – the quantity of heat. To do so, we would use the equation Q = m•C•ΔT. The m and the C are known; the ΔT can be determined from the initial and final temperature.

The value of a lid on the coffee cup is that it also reduces the amount of heat exchange between the water and the surrounding air. And any design of a calorimeter experiment must give attention to reducing the exchanges of heat between the calorimeter contents and the surroundings.

It is important to continuously stir the mixture because temperature is a measure of the kinetic energy of the particles and stirring provides kinetic energy to the mixture. It is important to continuously stir the mixture in order to keep the reaction going.

Stirring

1. Move the bottom of the flask closer to the stir plate.
2. Use a bigger stir bar.
3. Use a larger or more powerful stir plate (not all plates are created equal).
4. If your stir bar gets stuck somehow, pick up the flask and swirl it until the bar is free, or pry it free with a pipette or spatula.

It is important to continuously stir the mixture in order to keep the reaction going. If the stirring slows or stops, the reaction itself will stop.

StirringEdit Stirring or shaking the mixture will speed up the reaction rate. This is common sense. When you add sugar to a drink, you stir it because you know it will dissolve faster. Collision theory would predict this because the stirring would increase the number of collisions between reactant molecules.

is that stir is the act or result of stirring; agitation; tumult; bustle; noise or various movements or stir can be (slang) jail; prison while agitation is the act of agitating, or the state of being agitated; the state of being moved with violence, or with irregular action; commotion.

Concentration. If you increase the concentration of a reactant, there will be more of the chemical present. More reactant particles moving together allow more collisions to happen and so the reaction rate is increased. The higher the concentration of reactants, the faster the rate of a reaction will be.

The rate is proportional to the concentration of a reactant. When you double the concentration the rate doubles. The rate is proportional to the square of the concentration of a reactant. When you double the concentration the rate goes up four times.

The rate constant, or the specific rate constant, is the proportionality constant in the equation that expresses the relationship between the rate of a chemical reaction and the concentrations of the reacting substances.

If you halve the concentration, you halve the rate, and so on. The rate is proportional to the square of the concentration. Since concentration changes during an experiment, we must measure the initial rate of the reaction, before the concentration has had a chance to decrease.

Catalysts speed up chemical reactions. How does concentration affect the rate of a reaction? Increasing the concentration of the reactants will increase the frequency of collisions between the two reactants.

There are various factors which can help in increasing the rate of a reaction like addition of a catalyst, temperature, change in concentration etc. Thus, we can conclude that out of the given options how fast a reactant is used up to how fast a product is formed is the rate of reaction.

Rate Laws. Typically, reaction rates decrease with time because reactant concentrations decrease as reactants are converted to products. Reaction rates generally increase when reactant concentrations are increased.

In some reactions, the rate is apparently independent of the reactant concentration. The rates of these zero-order reactions do not vary with increasing nor decreasing reactants concentrations. This means that the rate of the reaction is equal to the rate constant, k, of that reaction.

We know that the unit of r(rate of the reaction) is molL. sec and of [reactant] (concentration of reactant ) is molL , So the unit of k will vary with the value of x(order of the reaction). Evidently, the Rate constant does not depend upon the unit of concentration for reaction of first order.