of mixture Metal C 25.605g 24.6mL 25.2°C 100.5°C 28.7°C Calculations: Show your work and write a short explanation with each calculation. Part I: 1. Calculate the energy change (q) of the surroundings (water). We can assume that the specific heat capacity of water is 4.18 J/ (g · °C), and the density of water is 1.00 g/mL. (4 points) q = m × c × Δt Given: q=?
Warm up questions: Exercise1： mass of ZnI2 is 2.56g The molar mass of ZnI2 is 319.18 g/mol The mole of ZnI2: 2.56g/319.18g/mol=0.00802mol 0.00802mol/(500*10-3L)=0.01604M 0.01604M ZnI2 should appear on the label of the flask. Exercise 2: Student 1: 0.43g zinc iodide The mole of ZnI2: 0.43g/319.18 g/mol= 0.00135mol 0.00135mol/0.01604M=0.084L 0.084L*(1000mL/1L)=84mL Student 2: 5.0*10-4 moles of zinc iodide. 5.0*10-4mole/0.01604M=0.031L 0.031L*(1000mL/1L)=31mL Molarity as a Concentration Unit Exercise 3: a. 2.56g ZnI2/500 mL of solution 2.56g/319.18 g/mol=0.00802mol 0.00802mol/(500*10-3L)=0.016M b. 0.00512g ZnI2/mL of solution 0.00512g/319.18 g/mol=1.6*10-5 mol 1.6*10-5 mol/(1*10-3L)=0.016M c. 0.00806 moles of ZnI2/500 mL of solution 0.00806mol/(500*10-3)L=0.016M d. 0.0161 moles of ZnI2/L of solution 0.0161mol/1L=0.016M Exercise 4: a.
What is the mass of object 1? __________19.5g_____________________ An object’s volume is the amount of space it takes up. The volume of an irregular object can be measured by how much water it displaces in a graduated cylinder. Place object 1 into the Graduated Cylinder. What is the volume of object 1?
Stoichiometry is a section of chemistry that involves using the relationships between reactants or products in a chemical reaction to determine the desired quantitive data. 4. Using the balanced chemical reaction between Sodium carbonate and Calcium Carbonate given in page 92 of your lab manual (first paragraph of procedure), find the mass of Sodium Carbonate (in grams) needed in reaction? Na2CO3(aq)+CaCl22H20(aq)-CaCO3(s)+2NaCl(aq)+2H2O Date:_____3/30/2015____________ Name______Chloe Flake______________ 1. Title: 1pt Stoichiometry Of A Precipitation Reaction 2.
You correctly answered: d. Because water and many plasma solutes filter into Bowman's capsule. In the presence of ADH, what component of the tubule fluid moves out of the collecting duct and into the interstitial space? You correctly answered: b. water Experiment Data: Urine Volume 80.57 40.28 26.86 16.86 Urine Concentration 300 600 900 1200 Conc. Grad. 300 600 900 1200 ADH present present present present 03/31/14 page 2 Post-lab Quiz Results You scored 33% by answering 1 out of 3 questions correctly.
The purpose of the experiment was to do a solution, which molarity is 0.20 mol/l, from water and an ionic compound. Our ionic compound was zinc sulfate (ZnSO4). Our task was to make one hundred milliliters (100 ml) of the solution. Materials To execute the experiment we used the following equipment: - a beaker - a volumetric flask - a plastic spoon - a scale - a pipette - a funnel - a cork cap We also used solid zinc sulfate (ZnSO4), and distilled and deionized water to make the solution. Calculations To figure out the amount of zinc sulfate that we had to add to the water, so that the molarity of the solution would be 0.20 g/mol, we did the following steps: First we calculated the amount of the zinc sulfate to add in moles.
The mass of the oxygen in the oxide product will represent how much added weight was gained in the reaction. Once the masses are calculated, several calculations involve forming the empirical formula. In equation 4, the metal and oxygen masses are converted to moles. In equation 5, the simplest ratio is needed to determine the molar ratio that represents the subscripts in the equation. The resulting ratio from equation 5 is then applied to form the empirical formula and a balanced
A fixed amount of water is added to a graduated cylinder and the volume of water is recorded. The object to be measured is then added to the graduated cylinder and the new volume is recorded. To determine the volume of the object the volume of water is subtracted from the volume of water with the object. Volume – Object = Volume object + water – Volume of water Materials: • Various percentages of zinc and copper mixtures o 0% Cu, 100% Zn o ~10% Cu, ~90% Zn o ~20% Cu, ~80% Zn o ~30% Cu, ~70% Zn o ~40% Cu, ~60% Zn o ~50% Cu, ~50% Zn o ~60% Cu, ~40% Zn o ~70% Cu, ~30% Zn o ~80% Cu, ~20% Zn o ~90% Cu, ~10% Zn o 100%Cu,0%Zn • Pennies o using 5, 10, 20 and 30 pre1982 pennies o using 5, 10, 20 and 30 post1982 pennies Procedure: 1.) From Penny Set A (Pre-1982), measure the mass of 1 penny and then of 2, 3, 5, 7, 9, and 13 pennies.
Laboratory Techniques and Measurements – Lab Report Assistant Exercise 1: Length, Temperature, and Mass Data Table 1. Length Measurements Object Length (cm) Length (mm) Length (m) CD or DVD 11.7 116.8 0.1 Key 6.1 61.0 0.1 Spoon 14.5 144.8 0.1 Fork 17.0 170.2 0.2 Data Table 2. Temperature Measurements Water Temperature (°C) Temperature (°F) Temperature (K) Hot from tap 65.1 149.2 338.3 Boiling 97.5 207.5 370.7 Boiling for 5 minutes 100.0 212.0 373.2 Cold from tap 23.0 73.4 296.2 Ice water – 1 minute 7.8 46.0 281.0 Ice water – 5 minutes 4.0 39.2 277.2 Data Table 3. Mass Measurements Object Estimated Mass (g) Actual Mass (g) Actual mass (kg) Pen or pencil 7.5 10.7 0.01 3 Pennies 8.0 7.4 0.007 1 Quarter 3.0 5.6 0.006 2 Quarters, 3 Dimes 15.7 18.2 0.02 4 Dimes, 5 Pennies 20.9 21.5 0.02 3 Quarters, 1 Dime, 5 Pennies 29.4 31.7 0.03 Key 8.6 10.0 0.01 Key, 1 Quarter, 4 Pennies 25.0 25.7 0.03 Questions: A) Water boils at 100°C at sea level. If the water in this experiment did not boil at 100°C, what could be the reason?
| 1st | 2nd | | Buret volume: 24mL | Buret volume: 24.1mL | W2 | 141.87g | 141.83g | W1 | 115.18g | 116.15g | ∆W = W2 – W1 | 25.06g | 25.37g | D = ∆W/buret volume | 1.04g/mL | 1.06g/mL | Average Density = 1.04 + 1.06 / 2 = 1.05 | I repeated the same process for the Mohr pipet as I did for the Buret. I found that the average density required for the egg to float is 1.09g/mL | 1st | 2nd | | Mohr volume: 23.2mL | Mohr volume: 23.02mL | W2 | 140.93g | 141.27g | W1 | 115.87g | 115.90g | ∆W = W2 – W1 | 25.06g | 25.37g | D = ∆W/Mohr volume | 1.08g/mL | 1.10g/mL | Average Density = 1.08 + 1.10 / 2 = 1.09 | I repeated the same process for the volumetric pipet as I did