Measuring H2O levels is the easiest and most accurate way to track how much water you're taking in each day and can help ensure you remain properly hydrated throughout your day. Gaining insight into your H2O intake as it relates to external factors can allow you to make adjustments that improve health - for instance reducing total dissolved solids in your water source. Water Activity Water activity, measured as the ratio between vapor pressure and that of pure water, can be measured using a water activity meter that measures headspace vapor pressure above sample trays. Once equilibrium has been achieved, an infrared beam focuses on the small mirror in its chamber to measure vapor pressure accurately. Vapor pressure of liquids like water is an integral component of food preservation. Sugars and salt can reduce this vapor pressure in food products by binding with it and making it less accessible to microorganisms. Controlling water activity is an effective way to limit microbial growth, as well as improve shelf life or texture in certain products like honey. Honey has an extremely low water activity (approximately 0.60) because the molecules of water bind with sugars in its makeup. Another factor affecting water activity is chemical and surface interactions between dissolved ingredients and undissolved ingredients in water, and undissolved ingredients themselves. Dissolved species interact with water through dipole-dipole, ionic, van der Waals forces; at the same time water molecules form bonds to starches, proteins and polymers found within foods via these forces. Water activity is an effective indicator of food safety because it reveals how much liquid is available for reactions such as non-enzymatic browning, lipid oxidation, protein denaturation and starch gelatinization. Water activity measurements are fast, accurate and economical tests that can be applied to raw materials or mid-production samples to monitor ingredient changes or processes before they impact final products. Their growing recognition has resulted in their incorporation into FDA and USDA regulations as well as GMP/HACCP requirements and NSF International Draft Standard 75 requirements. Water is indispensable to life on Earth and beyond; even in space where oxygen and other gases may not exist, water remains the source of sustenance for life. Water also serves as a solvent for other chemicals as well as reactant in many biochemical processes; hence its significance when considering food products and their components. Total Dissolved Solids One of the key components to understanding H2O is knowing how Total Dissolved Solids (TDS) affect your water quality. A high TDS level may have adverse consequences both on taste and aesthetics; an excess can even impact on how easy cleaning will be! An ideal TDS level should lie between 50 ppm and 1000 ppm, which you can measure using a TDS meter or reduce using water distillation or reverse osmosis filters to lower. Total Dissolved Solids are composed of the total sum of all dissolved and suspended solids in your H2O, such as salts, minerals and chemicals. There are various methods available for measuring TDS levels, but one of the quickest and easiest is with a TDS meter. This device uses electricity to conduct the ions present in water samples for measurement, providing you with an indication of your TDS levels whether at home or in the field. Gravimetric methods offer another means of measuring TDS levels; they tend to be more precise but also take longer. Gravimetric methods may be suitable for measuring TDS levels in water that contains large concentrations of inorganic salts; however, for measuring the presence of organic compounds or heavy metals more accurately. If conductingivity-based methods seem more suitable then gravimetric ones. To check your TDS levels, place the tip of a TDS meter into water and dip until an electrical charge of the ions passes through it and displays its value in milligrams per liter (ppm or mg/L). If you own a water distiller or RO system, testing its TDS level in its first tank of water fed into it will help ensure its safety to consume and that its filter hasn't become polluted with chlorine or other disinfectants from previous tanks. Relative Humidity Relative humidity measures how much moisture there is in the air relative to what its maximum capacity at a specific temperature is capable of holding. Absolute humidity provides you with a clear understanding of how much moisture there is in the air at any one time, while relative humidity allows you to determine how it may impact your home or business. By measuring both relative and temperature humidity levels together, you can make an accurate assessment of how humid the H2O in your environment really is, enabling you to take measures necessary for its comfort. As temperatures increase, relative humidity decreases; this occurs because warmer air has greater capacity to store moisture than its cooler counterpart. As you'll learn in the following section, the opposite is also true - when temperatures decrease relative humidity increases as air becomes drier and less humid (relative humidity increases). Dew point temperature marks the temperature where water vapor begins to condense into liquid water droplets as it condenses, initiating cloud formation and precipitation such as rain, snow or hail. To accurately measure relative humidity in an air mass, one needs to know both its actual vapor density and saturation vapor density, measured in grams per cubic meter. Once you know this information, an empirical fit can be used to calculate the percentage of water vapor actually present in an air parcel. It's an excellent way of getting an idea of relative humidity levels but remember it only works up to 40degC! Now that you understand how to calculate relative humidity, here are some examples to demonstrate what it means and its potential effect on your environment. Question 1: During wintertime, what would occur if outside temperature were 40 and dew point was 40? Question 2: In springtime, what might be expected if outdoor temperature were 70 and dewpoint was 55? Calculating relative humidity of an air parcel requires calculating its ratio between water vapor partial pressure in that parcel and saturation vapor pressure at its actual dry bulb temperature - known as RH factor or the RH value - and saturation vapor pressure at actual dry bulb temperature. Relative humidity monitoring is incredibly crucial and sensitive, as its impact can have serious ramifications on your comfort as well as that of those within your space, so always remain aware. Temperature Temperature of water plays an integral role in its quality and the wellbeing of aquatic wildlife, weakening it and making it more vulnerable to diseases and pollutants. Warm waters can weaken aquatic species more readily. Temperature plays an essential role in water's chemical and biological reactions, so measuring its temperature is critical for assessing its suitability for human consumption and use. Temperature can be measured using either a thermometer or thermocouple, both small electronic devices that change resistance values in circuits depending on temperature. You can find them at your local hardware store. In order to establish the temperature of a mixture, multiplying one body of water's mass and temperature with that of another body will give you its final temperature - in this instance the mixture itself. When measuring the temperature of a mixture, it is crucial that all necessary components are available. You will likely require a plastic cup with a hole for your thermometer as well as a container to contain any melted ice that accumulates during this process. Once you have all of the required materials, place the thermometer in a container filled with liquid for approximately one minute before taking its temperature reading and recording it on your Hydrosphere Investigation Data Sheet. Your water temperature may change slightly depending on both its ambient air pressure and your location. At sea level, its boiling point is 100deg Celsius while at high altitudes it is lower. Therefore, before placing your hand into water without first getting an understanding of its temperature. A thermometer can help, but to gain the best understanding it is best to simply hold your hand over the body of water before submerging your hand in.