In order to prepare 500 ppm of lead solution from lead nitrate dissolve 0.799 gm of lead nitrate in 1000ml of water--add 1 or 2 drops of nitric acid.
It depends on the volume, if we consider 1 liter of the solution 500 mg of sodium chloride is needed.
take 1mg (0.001g) of mannitol and dilute it by deionised water to 100ml in 100ml measuring flask.The resulting solution is 10ppm.and then make further dilution to prepare required concentration.
To dilute 1000 ppm to 500 ppm, you need to add an equal amount of the solution without any concentration. For example, if you have 1 mL of the 1000 ppm solution, you would need to add 1 mL of water to make it 500 ppm.
The majority of the Columbia river is considered freshwater, which makes it < 500ppm of dissolved salts.
Carbon dioxide gas is formed from the combination of two elements: carbon and oxygen. It is produced from the combustion of coal or hydrocarbons, the fermentation of liquids and the breathing of humans and animals. It is also found in small quantities in the atmosphere, around 300-500ppm
Assuming no other complaints you would only need to change water to lower the total dissolved solids level or cyanuric acid level. TDS should be below 500ppm and cyanuric acid ~50 ppm.
The Threshold Limit Value (TLV) for methane gas is set at 1000 parts per million (ppm) as a time-weighted average for an 8-hour workday. Concentrations above this limit may pose health risks to individuals exposed to methane gas.
They don't sell that anymore. There is Low Sulfur Diesel (less than 500ppm Sulfur) and Ultra Low Sulfur Diesel (less than 15ppm Sulfur). If your vehicle says "ultra low sulfur diesel required" you have a diesel particulate filter. (You might also have a Selective Catalytic Reduction reactor or an Advanced EGR system if you have a 2010-on truck, but if so you also have a DPF.) You can run LSD in your engine occasionally--like if you need some fuel because you're about out of gas and there's nothing else around--but running LSD all the time in a newer truck will ruin the diesel particulate filter and they are not cheap.
It depends on the concentration of the solution (5-10% home, 25%+ for commercial), and the time of exposure. Additionally, it depends on whether you've developed olfactory fatigue (you've gotten used to it). Your eyes burning, nose irritation and coughing generally tell you to get away. If you do, provided you haven't been exposed to extremely high concentrations, you'll be fine. If exposed to concentrations toward 500ppm (definitely not household use), it is a danger to your health. The negative results of exposure to ammonia can affect your respiratory system. Repeated exposure can cause respiratory tract irritation. Chronic bronchitis and airway hyperactivity have been reported in such cases. Of course, since ammonia is corrosive, getting it on your skin or eyes can cause burning, etc.
Pre 2007 diesel engines can run on 500 ppm diesel fuel. 2007 and later diesel engines that call for ultra low sulfur diesel fuel should not. These systems use EGR and the extra sulfur in the diesel creates sulfuric acid by nature and will then be reintroduced into the combustion process. Even later diesel engines are using diesel particulate filters that are sensitive to the extra sulfur. Bottom line, if your engine says that it is rated for ultra low sulfur diesel fuel (15ppm) use it.
Neutralize all chemicals in the pool and then drain it. Do the annual filter cleaning - thoroughly and refill the pool with fresh water and retreat chemically. Never empty a vinyl liner pool! The liner will shrink and you will not be able to get it stretched back. Why go through neutralizing the water when you are just going to empty it anyway! DUMB waste of chemicals. Just drain 1/2 of the water and add fresh then adjust the balances in the clean water.
You should first determine what the TA (Total Alkalinity)of YOUR pool should be. You can do this by having the Total Hardness (not calcium hardness)tested. (Examples shown below). Then adjust the TA to where it should be for YOUR pool. Raise by adding bicarb of soda, lower by adding acid a little at a time. When the TA is where it should be, then ajust pH. Some TA levels for various TH readings: TH 100 = TA 100-110 TH 200 = TA 90-100 TH 300 = TA 80-90 TH 400 = TA 75-85 TH 500 = TA 70-80 If TH is over 500ppm AND at least 300ppm above that of the fill water, empty pool and refill.