Investigating Heat Associated With Chemical Change

always exchanges energy with the surroundings. Energy exchange can occur as work or as heat

From this lab we can conclude that the main sources for energy of candles are oxygen, the wick, and wax in gas form. Although oxygen was not tested, it is know that all candles need oxygen and that when the candle’s supply of oxygen is restricted the oxygen will be used up and go out. The wick was proven to be a fuel when the string in step 2 lit on fire. Wax in gas form was proven in step 5 where the candle was lit without using the wick. Solid wax was disproved in step 3 when it melted into liquid wax. But liquid wax was also disproven when trying in step 4 to light it on fire. The lab successfully showed the process in which a candle burns when we observed the flame. When the candle is lit it is very clear that the wick pulls up the melted

Using a thermometer we observed the measurement of the water “H2O” in the beaker, and it resulted in an initial temperature of 20 ⁰ C.

Try to repeat the experiment to compare the weight of the candle instead of its height. Do you think there will be any difference in your findings?

You have the mass of water from calculation #9, the specific heat of water is 4.184 J/g(oC), and the temperature change of water

3. The volume of a fixed mass of a liquid sample increases as the temperature rises from 20 to

Mass of oxygen = final mass - initial mass = 0.08 g - 0.06 g = 0.02 g

The air pressure fell below the vapor pressure, and the water boiled. 10) Use your observations to compare the atmospheric pressure outside the beaker to the air pressure inside the beaker before lighting the candle. The pressure is equal before lighting the candle because the beaker took the air from outside the beaker, and nothing has been done to change the

After the flame of the candle was put off the condensation inside the beaker disappeared this could have happened due to environment error. Another possible error could be when the 15 mL of indicator solution Bromothymol Blue was taken from the beaker that contains the substance. The students did not have an increment of five on their beaker, the level ranged from 10-50mL when the students had to pour the substance into their 50 mL beaker they had to use common sense to figure out how much 15mL. When the students measured the substance they had to be precise, so they could get an accurate result. To see if water is part of a products of a combustion reaction practical errors like the wick of the candle was short and the wick was getting thinner, so heat could not reach the bottom of the beaker this

Chemical reactions that absorb energy are called endothermic reactions, these reactions are observed by a decrease in temperature of the reaction mixture.

Well, my project is based on lighting a candle, placing it in a bowl of water, covering the candle up with a glass bottle. Then, slowly watch the water rise, but how did it rise? Below is some research, based on these factors, and this experiment. First, I will start with the candle and the science behind it. A candle is made up of wax, and all waxes are essentially hydrocarbons.

According to the results, the hypothesis is correct, as the larger the container, the longer the flame is extinguished, the slower it will be extinguished. When the candle is covered with a bigger container, the amount of oxygen is greater near the candle. The candle uses oxygen during the ignition process as it is an important factor to keep it burning. Therefore, this amount of oxygen requires a longer period of time to keep the candle lit for a slower period of time compared to a smaller container that will determine the amount of oxygen less close to the candle and thus the candle will use this quantity in less time for ignition.

Mass of water x 4.2 (water’s specific heat capacity) x temperature change = energy transferred from the fuel to the water

3. Calculate the total heat released in each reaction, assuming that the specific heat of the solution is the same as for pure water (4.18J/gK). Use q=mcΔT. Show work here and record your answer in Data Table 2.

The heat gained by the unknown metal and the cool water(2) equals the heat lost by the hot water(1).