Solutions and pH Chemistry

Blood pH is tightly regulated between 7.35-7.45 in healthy individuals. 7.4 represents normal arterial pH. Options A (6.1), C (8.0), and D (8.8) are all outside physiological range - 6.1 indicates severe acidosis, while 8.0+ indicates dangerous alkalosis.

Let x be gallons of water added. The salt amount stays constant: 0.15 gallons (15% of 1 gallon). Final concentration: 0.15/(1+x) = 0.10. Solving: 0.15 = 0.10 + 0.10x, so 0.05 = 0.10x, giving x = 0.5. The dilution formula is: C1V1 = C2V2 where C2 is the target concentration and V2 is the final total volume.

Normal blood pH is tightly regulated between 7.35 and 7.45, which is slightly alkaline. This narrow range is critical for proper enzyme function and cellular processes. Option A (7.1-7.2) is too acidic and would indicate acidosis. Option D (7) is neutral pH, not physiological pH. Blood must maintain this specific alkaline range for survival.

Initial sugar = 4% of 6L = 0.24L. After 1L evaporates, the total volume is 5L. The sugar amount remains 0.24L. The new percentage is (0.24 / 5) * 100 = 4.8%. 4.8% is equivalent to the fraction 24/5%.

Since 75% of the solution is water, the remaining 25% must be pure acid. For 20 liters of solution, 25% × 20 = 5 liters of pure acid. Option A (15) represents the water portion, not the acid.

A pH of 7 indicates neutrality on the pH scale, which ranges from 0 to 14. Solutions with pH less than 7 are acidic, while solutions with pH greater than 7 are basic or alkaline. Pure water at 25°C has a pH of 7, representing perfect balance between hydrogen ions (H+) and hydroxide ions (OH-).

Pure water has a pH of 7 because it is neutral, meaning the concentration of hydrogen ions equals the concentration of hydroxide ions. The pH scale ranges from 0-14, with 7 being the neutral point. Pure water contains only H2O molecules with equal concentrations of H+ and OH- ions from autoionization.

Moles = concentration × volume. 0.6 mol/L × 4 L = 2.4 moles. This is a direct application of the concentration formula, showing how many moles are needed to achieve the desired molarity.

A pH of 7 indicates a neutral solution, meaning it has equal concentrations of hydrogen ions (H+) and hydroxide ions (OH-). Solutions with pH < 7 are acidic, while pH > 7 are basic.

The pH scale measures acidity and alkalinity. A pH of 7 is neutral, below 7 indicates acidity, and above 7 indicates alkalinity (basic). The lower the pH below 7, the stronger the acid. This is a fundamental concept in acid-base chemistry.

Pure water has a pH of 7, which is considered neutral on the pH scale (0-14). A pH of 7 means the concentration of hydrogen ions equals the concentration of hydroxide ions. pH values below 7 are acidic, while values above 7 are basic (alkaline). Pure water at 25°C has this neutral pH value.

pH measures the concentration of hydrogen ions (H+) in a solution on a logarithmic scale from 0-14. It indicates acidity or alkalinity - lower pH means higher H+ concentration (more acidic), higher pH means lower H+ concentration (more basic).

Pure distilled water has a pH of exactly 7, which is considered neutral on the pH scale (0-14). The pH scale measures acidity (below 7) and alkalinity (above 7). Option B is correct. A pH of 8 would be slightly basic, while 6 and 5 would be acidic.