140 likes | 193 Views
pH Scale. Neutral = 7.0 (Water). Increases by a factor of 10X. Increases by a factor of 10X. What makes acids and bases?. Preparing the pH indicator (Cabbage Juice). Obtain a chunk of red cabbage. Use scissors to shred the cabbage into one of your two beakers.
E N D
pH Scale Neutral = 7.0 (Water) Increases by a factor of 10X. Increases by a factor of 10X.
Preparing the pH indicator (Cabbage Juice) • Obtain a chunk of red cabbage. • Use scissors to shred the cabbage into one of your two beakers. • Rinse the scissors with water, but DO NOT DRY THE SCISSORS. • Add distilled water to the shredded cabbage until the water level is at the 200mL mark. • Wait 20-25 minutes. • Use the coffee filter and funnel to filter out the pieces of cabbage. Pour the cabbage juice into the second beaker. • Compost Cabbage, coffee filters and paper towels. • Rinse the beaker and clean up.
Relative pH Color Scale More Acidic---Less Acidic----Neutral---Less Basic---More Basic
Actual Results (End of Class) Coffee ≈ pH 5 Milk ≈ pH 6.5
Litmus Paper pH Indicator (Before) R=Red B=Blue N=Neutral
Litmus Paper pH Indicator (After) R=Red B=Blue N=Neutral
Red is usually associated with acids. • Blue is usually associated with bases. • Hydrangeas can change color based on the pH of the soil.
Neutralization:Acid + Base = Salt + Water Hydrochloric Acid HCl + Sodium Hydroxide + NaOH → Sodium Chloride →NaCl + Water +H20
The old vinegar (acetic acid) and baking soda (sodium bicarbonate) trick: Reactants Products Salt