The main objective of this experiment was to determine, which NaCl concentrated solution would allow the chickpeas to absorb the most solution. The course of the experiment was initially carried out over the course of 60 minutes, however the shorter time period did not permit the maximum water absorbance to be reached (i.e. a plateau of the graph). Therefore, the course of this experiment was carried out over 160 minutes, to observe the decrease in the rate of hydrolysis. Different concentrated NaCl solutions were used as the solutions that the chickpeas were soaked in, altering the maximum amount of water absorbed. As shown in Figure 1, the more dilute the NaCl solution is, the more water absorbance was taking place. Also, this trend can be
…show more content…
Since the NaCl compound has a molecular weight of 58.44 g/mol and water has a molecular mass of 18.01 g/mol, this shows that NaCl is a bigger molecule. The chickpeas surface undergoes osmosis, allowing for water and/or salt to move from a higher concentration in the surroundings to a lower concentration into the chickpea. Due to the size of the salt molecule, the chickpea will take in less NaCl molecules compared to water molecules to occupy the same space in the chickpea. Figure 2 is a graph of the normalized M(t) data, which shows an exponential increase in the beginning and a leveling off in the end. The leveling off is not only the maximum absorbance of a solution, but also the maximum amount of molecules that can fit in a fixed space (the chickpea). The initial sharp increase in the moisture content is due to the water or NaCl molecules going from a high concentration to a low concentration, which will happen quickly if a low concentration is immersed in a high concentrated solution. The molecules want to reach equilibrium as quickly as possible and will move to an area of low concentration as quickly as …show more content…
The Peleg equation relates the initial moisture content of the chickpea, which is assumed to be zero added to the division of time by the addition of k1 and k2 times time. K1 and k2 are constants that relate to the rate of hydrolysis of the chickpea. These two constants can be found using the least squares regression fit of the data through Solver in Excel. K1 is the Peleg rate constant and K2 is the Peleg capacity constant. Initially, k1 determines the initial water absorption rate, meaning that the higher the k1, the lower the initial absorption rate. K1 in this experiment was 62.21 for all three concentration values.6 The rate constant of k1 did not change drastically between concentration values because the Peleg equation only takes into account the moisture content at a specific time. Even though the constants did not change, the maximum absorbance values did change in comparison to the Peleg equation graph, shown in Figure 3. The two trials of the 0 M NaCl solution were very similar to the Peleg equation, if not exact; but as the concentration of NaCl increased, the maximum concentration was not as high. This means that more of the NaCl solution was absorbed relative to the water intake. Finally, the 3 M NaCl solution showed the least maximum absorbance of 0.3 (0.7 was the maximum absorbance for
Since the NaCl compound has a molecular weight of 58.44 g/mol and water has a molecular mass of 18.01 g/mol, this shows that NaCl is a bigger molecule. The chickpeas surface undergoes osmosis, allowing for water and/or salt to move from a higher concentration in the surroundings to a lower concentration into the chickpea. Due to the size of the salt molecule, the chickpea will take in less NaCl molecules compared to water molecules to occupy the same space in the chickpea. Figure 2 is a graph of the normalized M(t) data, which shows an exponential increase in the beginning and a leveling off in the end. The leveling off is not only the maximum absorbance of a solution, but also the maximum amount of molecules that can fit in a fixed space (the chickpea). The initial sharp increase in the moisture content is due to the water or NaCl molecules going from a high concentration to a low concentration, which will happen quickly if a low concentration is immersed in a high concentrated solution. The molecules want to reach equilibrium as quickly as possible and will move to an area of low concentration as quickly as …show more content…
The Peleg equation relates the initial moisture content of the chickpea, which is assumed to be zero added to the division of time by the addition of k1 and k2 times time. K1 and k2 are constants that relate to the rate of hydrolysis of the chickpea. These two constants can be found using the least squares regression fit of the data through Solver in Excel. K1 is the Peleg rate constant and K2 is the Peleg capacity constant. Initially, k1 determines the initial water absorption rate, meaning that the higher the k1, the lower the initial absorption rate. K1 in this experiment was 62.21 for all three concentration values.6 The rate constant of k1 did not change drastically between concentration values because the Peleg equation only takes into account the moisture content at a specific time. Even though the constants did not change, the maximum absorbance values did change in comparison to the Peleg equation graph, shown in Figure 3. The two trials of the 0 M NaCl solution were very similar to the Peleg equation, if not exact; but as the concentration of NaCl increased, the maximum concentration was not as high. This means that more of the NaCl solution was absorbed relative to the water intake. Finally, the 3 M NaCl solution showed the least maximum absorbance of 0.3 (0.7 was the maximum absorbance for