This consistently increased the objects height by 0.4cm so that I could determine my volumes easily. My dependent variable was determined in two phases. First I would measure the object's weight using a weight and then while the object was in water, because it was held by the weight on a hook I could then also measure the object' weight with the same weight. The original weight of the object minus its weight in water would then equal to the buoyancy of the object. The control variables were determined like this: 1) I used water only.
Now, take the same piece of plasticine tied with thread and immerse it into the measuring cylinder filled with water, by holding the thread. 6. Check the changes in the water level by subtracting the final volume (Current Volume) with the initial volume. 7. Record the change in water level as the volume of the piece of plasticine.
Name: ______________________ Date: ________________________ Student Exploration: Density Laboratory Vocabulary: buoyancy, density, graduated cylinder, mass, matter, scale, volume Prior Knowledge Questions (Do these BEFORE using the Gizmo.) Of the objects below, circle the ones you think would float in water. Why do some objects float, while others sink? ____________________________________ _________________________________________________________________________ _________________________________________________________________________ Gizmo Warm-up The Density Laboratory Gizmo™ allows you to measure a variety of objects, then drop them in water (or other liquid) to see if they sink or float. An object’s mass is the amount of matter it contains.
Density vs. Salinity Problem: Depending on the salinity of the water sample, what number will the hydrometer read? Background Info: Salinity is the measurement of dissolved salts in water. These dissolved salts affect the total density of the water that then are dissolved in. If one knows the density of pure water and how dissolved salts affect the density of the water one ca find the salinity of the water using density. A hydrometer in an instrument that measures density by using a calibrated bobber.
Purpose The purpose of this experiment is to demonstrate and verify the integral momentum equation. The force generated by a jet of water deflected by an impact surface is measured and compared to the momentum change of the jet. Apparatus The experimental apparatus consists of a water nozzle, a set of impact surfaces, a spring scale connected to a balance beam, a flow meter, and plumbing for recirculating the water. Figure 4.1 is a schematic of these components. The pump draws water from the collection tank and provides sufficient head for the water to flow through the nozzle and the flow meter.
If the value of spectrophotometer show reading more than 20 mg/m3 is found, the eutrophication henomenon might occur. OBJECTIVE 1) To determine the amount of chlorophyll a content in water sample. APPARATUS AND REAGENT * UV-1601 SHIMADZU UV-Visible Spectrophotometer * Filtering set * Vacuum pump * 0.47 mm GFC filter paper * Centrifuge tube * Quartz 1 cm curvette * 90% acetone * Magnesium carbonate (MgCO3) METHODOLOGY 1) A polyethylene bottle containing the seawater sample is inverted into the Milipore filtering equipment containing a membrane of fiberglass filter. The sample is allowed to filter under half atmospheric pressure vacuum. 2) Several drops of MgCO3 solution is added to the seawater as it is being filtered.
The equilibrium is of dynamic nature; means that both the forward and backward processes are taking place even at the equilibrium point but with the same speed. The equilibrium involving gases can be attained only in closed containers. At equilibrium, the concentrations of different substances involved in the process become constant at constant temperature. The equilibrium involving a solid dissolved in a liquid at a particular temperature is represented by the saturated solution. Question 3 The solubility of a gas in a liquid is given by Henry's law.
Mass and Volume Relationship Purpose: The purpose of the lab was to find out if there is a constant relationship between mass and volume of a given substance which happens to be water. Volume of water (mL) Total mass of water and cylinder (g) 0.00 100.425 10.00 110.354 20.00 120.269 30.00 130.231 40.00 140.234 50.00 150.247 60.00 160.181 70.00 170.119 80.00 180.043 90.00 189.974 100.00 199.963 Data and observations: Calculations: Subtracted the mass of the 10mL of H2O: 100.354-100.425=9.929 20mL: 19.844g 30mL: 29.806g 40mL: 39.809g 50mL: 49.822g 60mL: 59.756g 70mL: 69.694g 80mL: 79.618g 90mL: 89.549g 100mL: 99.583g Questions: 1: The volume predicted for 36g of water is? 2: The mass predicted for 54cm3 of water is? 3: The percent error was found to be? Slope from #2-0.998g/mL x 100 4. a.
Assessed Practical: Planning Introduction: The aim of this experiment is to find the enthalpy change for the decomposition of sodium hydrogen carbonate. 2NaHCO = Na2CO3 + CO2 + H2O Using the enthalpy change of the following reactions. Sodium Hydrogen Carbonate: NaHCO3 + HCl = NaCl + CO2 + H2O Sodium carbonate: Na2CO3 + 2HCl = 2NaCl + CO2 + H2O Apparatus Sodium hydrogen carbonate Sodium carbonate Polystyrene Cup x 2 Measuring cylinder 50cm³ x 2 Weighing scale Weighing boats Thermometer degrees Spatula HCl acid 2M Prediction Background Information Hess' Law states that the enthalpy change for a reaction is the same whether the reaction occurs directly or in steps. This is a direct consequence of the fact that enthalpy, is a state function. One of the applications of Hess' Law is to determine the enthalpy change for a reaction by combining other reactions to get the desired reaction, then combining the enthalpy changes for the reactions to get delta H for the reaction under consideration.
The empirical formula would HO, because the ratio is 1:1. To determine the empirical formula of a compound, the mass of each element must be found. The mass is then converted to the amount of moles of the element. Once the mass of each element is converted to mole, the smallest mole is divided by each of the other moles to determine the ratio of each element. This will give the whole number ratio of each element.