An Investigation into the Enthalpies of the Combustion of Alcohols

In this experiment the scientists are looking for how gas production is effected when different sized Alka-Seltzer tablets are put into water. The independent variable is the different sizes while the dependent variable is the amount of gas produced. A constant variable includes the same brand of Alka-Seltzer tablets, the volume of water and same starting temperature. Finally the scientist’s control variable is the first trial testing the whole tablet comparing its reaction time to each new piece.

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5- Place 3 ½ oz. container of White chocolate into boiling pot as it is heating up

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The "y" speaks to the quantity of prey(squares) eaten or the quantity of squares taken. The "a" value represents the functional reaction that will be calculated. This depends on the degree of scanning for the squares. The "T" value presents the time and "x" value represents the square density. For this experiment the dependent variable “y” will change with each analysis. Also, the independent variable is “x” which changes for every trial (10, 20, 50, 100, 200). The span of each analysis is one minute, which is the value “T” and that stays the same it doesn’t change at all. The calculation of the other variables determines the actual variable for this

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The experimental question is Will the amount of air pressure change the height the rocket flies?. The independent variable is the amount of pressure in the rocket. The dependent variable is how high the rocket flies. The control is a bottle with just air no water launched at 60psi.

In my experiment, I decided to look at how or if different liquids effect the growth of a tomato plant. The independent variables in this experiment were the liquids that the tomato plants were watered with. The dependent variables in this experiment were the speed that the plants grew and the amount that they grew throughout the two weeks that they were measured. I hypothesized that if the tomato plant is watered with river water, then the plant will grow the tallest.

In this lab, there are two days. In the first day, there are is part A and part B. Part A is further divided into three experiments. In experiment one, we were to figure out the heat capacity of the calorimeter that we made. The next two experiment’s goal was to calculate the enthalpy of 2 reactions and using hess’s law, figure out the heat of formation of magnesium oxide. In a reaction, there are

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For this experiment we where trying to find out what are some of the produces of combustion? To start out we made a list of possible products of combustion for a candle. The only thing that we really thought about was the carbon monoxide that is produced. For the experiment we took a candle, a 1000 mL and 500 mL beaker, cobalt chloride paper, and lighter. We first put the 1000 mL beaker over the candle, which we lighted with the light, then after the candle created a fog like form on the beaker. We stopped and right away rubbed the cobalt chloride paper over the fog, which was in the beaker and was caused by the water. Very shortly after the cobalt chloride paper turned from a blue into light pink color. After this we put water on the strip,

This graph is identical to experiment 1 graph 1 as it compares the experimental and theoretical molar heats of combustion. Being the same concept this graph shows how the experimental molar heat of combustion is a scale less than the theoretical molar heat of combustion. The significance behind the scale of this graph where the experimental is lower that the theoretical, is how there is a pattern for which every fuel follows the same trend. Also it shows the average heats of combustion and which alkane has the leading heat output rate.

Variables: In this experiment, the temperature (in degrees Celsius) of the chemicals is the independent variable. To change the temperature, the materials are placed in a bath of water being heated by a hotplate.

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