Ammonium chloride caused the water to cool. This means that the Ammonium chloride drew energy from the water to help it dissolve. As a result of losing its energy, the water cooled down. Calcium chloride caused the water to warm up. This means that energy from the calcium chloride was released and the water absorbed this heat. As a result, the temperature of the water increased. 3. Since you are measuring the temperature of the water, let’s call that the system. Relative to the water, was this process of dissolution endothermic (absorbing energy) or exothermic (releasing energy)?
If the water is considered the system the the dissolution of the ammonium chloride was exothermic because the water lost energy. Since the temperature of
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Now lets call the ionic substance the system and the water the surroundings. Relative to the ionic substance, was this dissolution process endothermic or exothermic?
If the ionic substance is considered the system then in the dissolution of ammonium chloride, an endothermic reaction occurred. The system is gaining energy from its surroundings which are losing energy. The colder water around the ammonium chloride shows that it gave up energy to the substance. In the calcium chloride reaction, an exothermic reaction took place. This is because the system is releasing energy into its surroundings. The warmer water around the calcium chloride shows that it received energy from the substance. 5. Based on this, which compound is more stable as an ionic solid and which compound is more stable as an ionic solution? Which would you assume has a higher enthalpy in its pure solid form?
Calcium is more stable as an ionic solution. The reaction between this substance and water is exothermic. This means that it’s enthalpy is negative and that the bonds of the products are ultimately stronger. Therefore, ammonium chloride must be strong as a solid. The reaction between ammonium chloride and water was exothermic. The enthalpy of this reaction is positive, which means that the reactants of the products are more
Two solutions were prepared by using Calcium Nitrate Ca(〖NO_3)〗_2 with concentration of 0.101 M, Potassium Iodate KIO_3 with concentration of 0.100 M, and deionized water. First solution contained 25.0 mL of Calcium Nitrate and 25.0 mL of Potassium Iodate. In the second solution, 15.0 mL of deionized water were added with 10.0 mL Calcium Nitrate and 25.0 mL of Potassium Iodate. Each of these solutions was mixed for 15 minutes. After the reaction of the solutions took place, each of the solutions was filtered. To remove water liquid from the filtered solution, both of the precipitates in the
Thermodynamics is essentially how heat energy transfers from one substance to another. In “Joe Science vs. the Water Heater,” the temperature of water in a water heater must be found without measuring the water directly from the water heater. This problem was translated to the lab by providing heated water, fish bowl thermometers, styrofoam cups, and all other instruments found in the lab. The thermometer only reaches 45 degrees celsius; therefore, thermodynamic equations need to be applied in order to find the original temperature of the hot water. We also had access to deionized water that was approximately room temperature.
Afterwards, we conducted crystallization to evaporate the liquid in an attempt to detect the presence of a salt. Before stating which of the potential
Common salt is another word for table salt. Table salt was researched to have the most of sodium chloride and actually has ninety-nine point nine percent (“Natural sea salt - will not cause high blood pressure”, n.d.). The researcher thinks it will increase the boiling point in water the most because it has the highest amount of sodium chloride present. Common salt is said to be the most used matter in the chemical world. Salt is translucent and can create electricity if melted. It is also known to melt ice or snow because it can be added to water to create a mixture that has a lower freezing point than purified water (Aasen, et Al 1999).
Ionic liquids (ILs) are liquids composed entirely of ions. Molten salt is the term normally reserved for those systems that are liquid at high temperatures, for example NaCl (table salt is a liquid at ≈ 800 0C). Room-temperature ILs are liquid below 100˚C, have received considerable attention as substitutes for volatile organic solvents. Due to their remarkable properties, such as negligible vapour pressure, large liquidous range, high thermal stability, good ionic conductivity, high electrochemical stability, they are considered favourable medium candidates for chemical syntheses. ILs are usually categorized into four types based on their cation segment: 1) alkylammonium-, 2) dialkylimidazolium-, 3) phosphonium- and 4) N-alkylpyridiniumbased ILs (Figure 1). Ionic liquids are generally composed of a bulky organic cation, such 1-butyl-3 methylimidazolium and typically an inorganic anion such as a halide. Below are the chemical structures of some common cations and anions used to make ILs.
The reason I believe this is that chemical reactions occur when particles of the reacting substances collide. Increasing the number of the particles increases the number of collisions per second and this increases the reaction rate. In the reaction between hydrochloric acid and calcium carbonate you can increase the number of particles in two ways. The first of these is to increase the surface area of the calcium carbonate.
Specific heat capacity of aqueous solution (taken as water = 4.18 J.g-1.K-1). T = Temperature change (oK). We can thus determine the enthalpy changes of reaction 1 and reaction 2 using the mean (14) of the data obtained. Reaction 1: H = 50 x 4.18 x -2.12.
During this reaction the solution gained heat. This is what we were monitoring. The reason why the solution gained heat is because the reaction lost heat. Energy is lost when two elements or compounds mix. The energy lost/ gain was heat. Heat is a form of energy as stated above in the previous paragraph. The sign of enthalpy for three out of the four reactions matches what was observed in the lab. For the last reaction, part four, the reaction gained heat not the solution like parts one through three. The negative enthalpy value for part four indicates that the reaction gained
The presence of a colored precipitate represents a pattern in the electron configuration of cations. When the outer p orbital of the ion of the metal is full, the precipitate of the product is white and no other color is present. When the outer d orbital of an ion is not completely full, the precipitate of the product is a true color. When the d orbital is completely full, the color of the precipitate is not a true color. Magnesium sulfate, aluminum chloride, and calcium chloride had a white precipitate after reacting with sodium hydroxide. Sodium chloride remained a clear liquid. The ions of magnesium, aluminum, calcium, and sodium have complete outer p orbitals and have no d orbitals. The precipitates and/or the liquids were colorless because
Osmosis is also another type of diffusion where water is transferred from a higher concentration to a lower concentration. Osmosis will then come into play when a membrane that differs in solute concentration breaks in two; the water will move from the hypotonic solution to a hypertonic solution. Initially, the hypotonic solution has a lower concentration, and the hypertonic solution has a higher concentration. The water will then continue its journey down its concentration gradient until it reaches equilibrium; that means the water will have the same solute concentration on both sides. When the solute reaches equilibrium on both sides of the semipermeable membrane, the solution then becomes isotonic. Isotonic solutions are when the solute concentration is the same on the inside and outside of the cells, and that is the reason most cells live in the isotonic state. Additionally, a semi-permeable membrane only permits specific substances to enter, usually opening for a solvent but not most solutes. The substances dissolved in a solution are referred to as a solute; and the solvent is the substance that dissolves a solute in a solution. Therefore, the mixture of a solvent and a solute
In a 100ml beaker 30mls of water was placed the temperature of the water was recorded. 1 teaspoon of Ammonium Nitrate was added to the water and stirred until dissolved. The temperature was then recorded again. This was to see the difference between the initial temperature and the final temperature.
This is expressed as Δ +ve (delta positive). If the total energy put in is less than the energy created, then the substance warms up (it is exothermic). This is expressed as Δ -ve (delta negative). I will investigate eight different alcohols using an alcohol or spirit burner, to measure the energy change during burning by measuring the change in temperature of some water held in a container.
Rate of Reaction Between Calcium Carbonate and Hydrochloric Acid Plan: In my experiment I will measure the rate of reaction between calcium carbonate and hydrochloric acid. The rate of the reaction is the speed that the reaction takes place so by measuring the rate I will measure the amount of time the reaction takes. Hydrochloric acid is a strong acid that is found in digestive juices in the stomach, it is also used for cleaning metals before they are coated. Calcium carbonate has a few forms including chalk and limestone the main use of these two materials is in the making of concrete, which is used for many things such as buildings. When you put calcium carbonate and hydrochloric acid together they react to form calcium chloride, carbon dioxide and water.
The Effect of Temperature on the Rate of Reaction Between Hydrochloric Acid and Calcium Carbonate
Methodology: A plastic cup was filled half way with crushed ice and mixed with four spoonfuls of 5 mL of sodium chloride. A thermometer was quickly placed inside the cup to take the temperature and the