I. Title: Mass and Mole Relationships in a Chemical Reaction II. Background: Percent yield is the ratio of actual yield to theoretical yield. Amount in percent of one product formed in chemical reaction. Actual yield is the information found is experiments or is given. It is also the real amount. Theoretical yield is found through a mathematical equation. The amount produced is another way of identifying theoretical yield. The limiting reactant is the reactant that is completely used in the reaction. This amount of the limiting reactant makes the amount of products formed smaller than should be. It, also, stops the reactions. The excess reaction is the reactant that is not used up completely in the reaction. Limiting reactants can be found …show more content…
In reactions, this law says that the mass of the original substance is the same after going through a reaction. This is shown with balanced chemical equations. It is needed so that the mass of the product is equivalent to the mass of the reactants. Mole ratio is the ratio of moles of one substance to the moles of another substance in a balanced equation. Mole ratio is considered a conversion factor since it helps to convert units with the use of moles. It is used in stoichiometry and other calculations and comes out of the balanced chemical equations. Stoichiometry is the measurement of elements that concerns the chemical quantities produced or taken in a reaction. The process of relating the mass and mole quantities of reactants or products in a reaction. It uses a balanced chemical equation, mole ratio, and sometimes needs mole mass. Molar mass is the mass in grams in one mole of substance. The units for molar mass are in grams per mole. Molar mass is the same number as the formula mass that needs to be found except it is converted. Formula mass is the mass in atomic mass unit of one particle of …show more content…
The items that were massed were the evaporating dish, watch glass, and NaCO3. The materials were massed once before and once after being heated in the drying oven. The mass of the evaporating Dish before was 46.57 g; while after being heating was 60.15 g. The mass of the watch glass before was 57.97 g and after was 48.75g. There were two masses taken for the substance NaHCO3- one with the evaporating dish and one without, subtracted out after the lab was concluded. The mass of the substance with the dish was 48.79 g before and 62.33 g after; meanwhile, the mass of the substance without the dish was 2.22 g before and 2.18 g after. The mass of the NaHCO3 had changed after the reaction occurred along with after it was placed on the hot plate and being in the drying oven. When the reactants were in the evaporating dish with the hotplate on, the acetic acid and sodium had been chemically bonded in a combustion compound. The mass went from two different reactants to one product and two evaporated
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Calculation: Initial Mass(g)－Final Mass (g)=Change in Mass (g) Trial 1 74.5-62.0=12.5(g) Trial 2 272.7－271.5=1.2（g） Percent Error: 272.7-271.5 x 100 272.7 ＝0.440% Percent Change: 74.5-62.0 x 100 74.5 (Trial 1) =16.778% 272.7-271.5 x 100 272.7 (Trial 2) ＝0.440%
Molar mass is the mass (in grams) of one mole of a substance. Using the atomic mass of an element and multiplying it by the conversion factor grams per mole (g/mol), you can calculate the molar mass of that element. First, find the chemical formula for the compound. Then, calculate the relative atomic mass of each element in the compound. Next, calculate the molar mass of each element in the compound.
Molar mass is the quantity in grams of one mole of a substance. The molar mass is found by adding the number of grams of each element to find the total amount of grams per mole. For example CaH2 has the elements of Calcium which has the molar mass of (40.078g/mole) and two Hydrogen which is (2 x 1.0079 g/mol).When the mass of both elements are added the molar mass of CaH2 is 42.0938g/mol. Moles are really important because it allows chemist to be able to have a standardize meausment which gives them the chance to compare compounds.
Another five tea bags were soaked for fifteen seconds in beaker B and then removed. The same teabags were then placed into beaker C for two minutes. They were removed after the time elapsed. 4. The solutions were allowed to cool to room temperature using an ice bath.
A hot plate was placed under the ring stand. 50 mL of 3.0 M NaOH in a 250 mL beaker and a stir bar was placed in the beaker. The beaker with NaOH was placed on the hot plate and 3.75 grams of NaAlO2*5H2O was placed in the beaker. The temperature probe was placed in the beaker with the solution, not touching the bottom of the beaker. The solution was heated and stirred till the solution dissolved.
To determine the rate of reaction there are many method to be used for example, measuring the mass after the product has been added and measuring the difference in mass on the duration of a digital scale. Another method, which will be used in this experiment is using a gas syringe to measure the volume of the gas which has been produced. The cylinder inside, will be pushed out to show a quantitative presentation of the volume produced by the reaction. Hypothesis
There are a series of steps that someone must go through to determine equilibrium constants for reactions at chemical equilibrium. The first step is to write a balanced chemical equation. However, before the chemical equation can be written, the reaction must be at equilibrium. Next, an equilibrium expression has to be written. In order to write the equilibrium expression the product concentrations are placed in the numerator while the reactant concentrations are placed in the denominator.
The Calorimeter Calorimetry is the science that was first recognized by a Scottish physician and the scientist Joseph Black. It is related with determining the variation in energy of a system by measuring the heat transfer with the surrounding. It is derived from the word calor in Latin, which means the heat and the pressure. Calorimeter is the device used in the calorimetry science to measure the quantity of heat transported from or to an object. Heat is the transfer of thermal energy between two bodies that differs in temperature (Mc Graw Hill Education).
Physics Coursework 1.1(a) Discuss why metric and SI system is better to use in measurement. Explain and list at least 6 physical quantities scientists use in measurements. There are several reasons as to why using the Metric System and SI Units are better to use. Each measurement has only one unit of measure regardless of the size which makes it a lot simpler to understand.
→ Concentration: Increasing the concentration of reactants in solutions increases the frequency of collisions between particles and so increases the rate of reaction → Pressure: Increasing the pressure of reacting gases also increases the frequency of collisions and so increases the rate of reaction → Catalysts: Catalysts speed up the rate of a chemical reaction but do not change itself Different catalysts are needed for different reactions in order to be most efficient Catalysts are used whenever possible in industries to increase the rate of reaction and reduce energy costs