Group IV Project: Unique Properties of Water
There are different properties (anomalies) of water which are unique. The uniqueness of water comes from its molecular structure. The polarity of water molecules is a consequence of hydrogen bonding. The meaning of polarity is that the molecule has both a positively and a negatively charged end, so water has a slight positive and slight negative charge on opposite ends. Water’s polarity is in charge of dissolving other molecules like sugars and ionic compounds. Water is known as the “universal solvent” because it has the ability of dissolving many substances. A water molecule is made when two hydrogen atoms are combined with one oxygen atom. Cohesion is where molecules tend to stick together due to hydrogen bonding, meaning that hydrogen bonding can hold together water molecules. The specific heat of water is much more higher than the specific heat of other substances. Water is known to exist in three different states, which are a solid, a liquid, or a gas. Water is a liquid between 0 degrees Celsius and 100 degrees celsius, which is the temperature range from freezing point to boiling point.
An experiment involving the uniqueness of water is the “droplets on a penny” experiment. The aim of this experiment was to show the cohesion and surface tension of water molecules. To do this experiment, a penny, eyedropper, and water will be needed. The eyedropper should have water in it so the water droplets can fall onto the penny. The water droplets are to be counted until any amount of water runs off the edge of the penny. The number of droplets are to be recorded.
Trial 1 Trial 2
Water (amount of droplets on penny) 20 26
Cohesion is present in the “droplets on a penny” experiment because as the H2O molecules fall upon the penny, they attract each other to make a bigger H2O molecule. Surface tension is present since it describes the cohesion between water molecules. After a certain number of droplets are on the penny, the water overflows, causing the molecules to separate from each other.
Another experiment is the “specific heat capacity of water” experiment. In this experiment, the aim is to find specific heat capacity of water by measuring temperature change at certain time periods. The materials needed for this experiment are a stopwatch, electric heater, thermometer, and water. The procedure is to have water heated in the electric heater and using a thermometer measure the temperature change at time periods of 30 seconds, 1 minute, 1 and half minutes, and 2 minutes.
First, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder. This water was then poured into the styrofoam cup that will be used to gather the hot water later. The water level was then marked using a pen on the inside of the cup. The water was then dumped out, and the cup was dried. Next, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder, and the fish tank thermometer was placed in the water. Once the temperature was stabilizing in the graduated cylinder, the marked styrofoam cup was filled to the mark with hot water. Quickly, the temperature of the regular water was recorded immediately before it was poured into the styrofoam cup. The regular/hot water was mixed for a couple seconds, and the fish tank thermometer was then submerged into the water. After approximately 30 seconds, the temperature of the mixture leveled out, and was recorded. This was repeated three
The purpose of this lab was to calculate the specific heat of a metal cylinder
When in solution, the hydronium and chloride ions formed will be partially surrounded by water molecules via ion-dipole bonds, an electrostatic force of attraction that exists between charges in the ions and the partial charges in the water molecules. Water molecules surrounding ions is called hydration.
2. What observation leads you to believe there is a force of attraction between water
Variables --------- During the experiments, the water will be heated using different spirit burners containing different alcohols. I will be able to change different parts of the experiment. These are the. Volume of water heated:
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.
Tf-Ti). Next, subtract the initial temperature, 25 degrees from the final temperature, 29 degrees putting the change in temperature at 4 °C. To calculate the heat absorbed by the water in calorimeter, use the formula (q = mCΔT). Plug in 50 mL for (m), 4.184 J for (C) and 4 °C for the initial temperature (ΔT), then multiply.
The purpose of the lab was to show the effect of temperature on the rate of
fuel, heat loss and shape of the type of wick. The type of fuel, heat loss will be the variables to change. We will measure to control the temperature of the water using a
Water is the most important molecule that exists on the Earth. Without water living beings would not be able to live. Water is used for an immeasurable number of things. There are many properties of water, which makes this molecule so unique. One which people overlook is hardness. Hardness is defined in the Chemistry: The Central Science by Prentice Hall's as being "water that contains a relatively high concentration of Ca2+, Mg2+, and other divalent cations." Water containing these ions is not a health hazard; however, it is a problem for industries and households. Therefore, the hardness of water is vital to understand in order to prevent the problems it could cause.
The last part of experiment 5, was learning about specific gravity and temperature. Specific gravity does not have any units, it is unitless. When measuring for the temperature, we used a thermometer to calculate the Celsius of the water, 10% sodium chloride, and isopropyl alcohol. The specific gravity uses a hydrometer to measure the gravity of the liquids. Using the hydrometer, to figure out the measurements we have to look at it from top to bottom. The water for specific gravity was .998 while the temperature of it was 24
For this experiment we took two different molecule and virtually dissected them finding everything about them including: bond length, bond angles, the charge on each atom, the non bonded distances between atoms and the energy difference between the highest and lowest molecular orbital.
Water has importance inside cells and outside. This may be because of its chemical and physical properties; it can be found naturally in all three of its states. At room temperature water is in a liquid state, It boils at 100ºC and freezes at 0ºC. However its molecules are bonded together by hydrogen bonds, this raises it's melting and boiling points, e.g. its boiling point would be -120ºC rather than 100ºC. Water can also be used as a solvent because of it polarity. Many things will dissolve in it, and more reactions take place while in solution with water.
Each water molecule consists of one oxygen atom and two hydrogen atoms. The oxygen atom (or the apex of the water molecule) bears a slight electronegative charge while hydrogen possesses a more positive one. Because opposite charges attract, the water molecules are drawn together. When an oxygen atom is linked to a neighboring molecule's hydrogen atom, a bond called a hydrogen bond is formed. In an ice crystal the hydrogen bonds to give the shape of the crystal so that the grid of molecules surrounds relatively to large spaces. In a liquid form, water has no such spaces; so ice is less dense and will float on liquid water. If not for this, great bodies of water would freeze from the bottom up without the insulation of a top layer of ice and all life in the water would die.