Search results
Results from the WOW.Com Content Network
Carbonate hardness, is a measure of the water hardness caused by the presence of carbonate (CO 2− 3) and bicarbonate (HCO − 3) anions. Carbonate hardness is usually expressed either in degrees KH (from the German "Karbonathärte"), or in parts per million calcium carbonate ( ppm CaCO 3 or grams CaCO 3 per litre|mg/L).
In these parts of Canada, the total hardness in ppm of calcium carbonate equivalent frequently exceeds 200 ppm, if groundwater is the only source of potable water. The west coast, by contrast, has unusually soft water, derived mainly from mountain lakes fed by glaciers and snowmelt. Some typical values are: Montreal, Quebec: 116 ppm [41]
As a unit 1 dKH is the same as 1 °dH which is equal to approximately 0.1786 mmol/L or 17.86 milligrams (mg) of calcium carbonate per litre of water, i.e. 17.86 ppm. [citation needed] The measurements of total hardness (German Gesamthärte (GH)) and carbonate hardness (German Karbonathärte (KH)) are sometimes stated with units dKH and dGH to ...
Mohs hardness of materials (data page) Vickers hardness test; Brinell scale This page was last edited on ...
The grain per gallon (gpg) is a unit of water hardness defined as 1 grain (64.8 milligrams) of calcium carbonate dissolved in 1 US gallon of water (3.785412 L). It translates into 1 part in about 58,000 parts of water or 17.1 parts per million (ppm). Also called Clark degree (in terms of an imperial gallon).
A seasonal greeting card, whether handwritten on personalized Christmas stationary or typed out on a tasteful e-card, is one way to show family and friends you care about them this holiday season ...
When testing coatings, scratch hardness refers to the force necessary to cut through the film to the substrate. The most common test is Mohs scale, which is used in mineralogy. One tool to make this measurement is the sclerometer. Another tool used to make these tests is the pocket hardness tester. This tool consists of a scale arm with ...
Roughly 46% of total decoration-related fires were started by candles in December, compared with about 32% for the other 11 months of the year, according to the National Fire Protection ...