CWEA Grade 4 Test Part 2 Exam With 100% Correct Answer 2025/2026

CWEA Grade 4 Test Part 2 Exam With 100% Correct Answer 2025/2026 Acid: - answer-A substance which releases hydrogen ions when dissolved in water. Most acids will dissolve the common metals and will react with a base to form a neutral salt and water. An acid is the opposite of an alkali, has a pH rating lower than 7.0, will turn litmus paper red, and has a sour taste. Acidity: - answer-The quantitative capacity of water or a water solution to neutralize an alkali or base. It is usually measured by titration with a standard solution of sodium hydroxide, and is expressed in ppm or mg/L of its calcium carbonate equivalent. Accuracy: - answer-The difference between the readings of an instrument and true value of what is being measured, expressed as a percent of full instrument scale. Air Gap: - answer-A clear vertical space through the free atmosphere, between the lowest opening of any pipe or faucet conveying water or waste to a tankplumbing fixture receptor or other device, and the flood level rim of the receptacle. An air gap is used to prevent cross connection between a water treatment device and a possible source of wastewater, thereby preventing a reverse flow of water from the sewer into the water supply system. Without an air gap, such reverse flow could occur due to an increase in the pressure in the sewer system or the creation of a negative pressure in the water supply line. Local plumbing codes usually require the air gap to be twice the diameter of the inlet, with a minimum width of 1.5 inches.