Q: Answer the following question given this paragraph: We all enjoy a cool dip in a swimming pool on a hot day, but we may not realize the work needed to keep that water safe and healthy. The ideal pH for a swimming pool is around 7.2. The pH will change as a result of many factors. Adjustment can be accomplished with different chemicals depending on the tested pH. High pH can be lowered with liquid HCl (unsafe material) or sodium bisulfate. The bisulfate anion is a weak acid and can dissociate partially in solution. To increase pH, use sodium carbonate. The carbonate anion forms an equilibrium with protons that results in some formation of carbon dioxide. Q: Liquid hcl can be used to do what to the ph of a swimming pool? Choices: - increase it - raise it - heighten it - lower it A:
A: lower it

Q: Answer the following question given this paragraph: Platelets are cell fragments involved in blood clotting. They stick to tears in blood vessels and to each other, forming a plug at the site of injury. They also release chemicals that are needed for clotting to occur. Q: What is the term for the cell fragments involved in blood clotting, which stick to tears in blood vessels and to each other? Choices: - molecules - droplets - cells - platelets A:
A: platelets

Q: Answer the following question given this paragraph: Christopher Auyeung, using bat image by User:Rugby471/Wikimedia Commons. Bats use echolocation to identify the location of objects . CC BY-NC 3.0 (bat image available under public domain). Q: What do bats use to determine the location of objects? Choices: - infrared light - UV light - syncopation - echolocation A:
A: echolocation

Q: Answer the following question given this paragraph: It may seem as though burning destroys matter, but the same amount, or mass, of matter still exists after a campfire as before. Look at the sketch in Figure below . It shows that when wood burns, it combines with oxygen and changes not only to ashes but also to carbon dioxide and water vapor. The gases float off into the air, leaving behind just the ashes. Suppose you had measured the mass of the wood before it burned and the mass of the ashes after it burned. Also suppose you had been able to measure the oxygen used by the fire and the gases produced by the fire. What would you find? The total mass of matter after the fire would be the same as the total mass of matter before the fire. Q: It may seem as though burning destroys matter, but the same amount of what, still exists after a campfire as before? Choices: - termperature - concentrations - energy - mass A:
A: mass