Lab acids bases pH scale
In this lab we will gain an understanding of:
* basic differences between the properties of acids and bases
* learn the role of hydrogen and hydroxide ions in acids and bases
* comprehend the nature of the pH scale with regards to acid and base strength.
What we will do:
* examine the effects of acids and bases on several chemical pH indicators
* determine the pH of several common household materials
* use the knowledge gained to determine the composition of unknown clear solutions.
1 Deionized water, 25ml
1 Dilute acid (0.1M HCl), 25ml
1 Dilute base (0.1M NaOH), 25ml
1 0.5% litmus, 25ml
1 0.02% methyl red, 25ml
1 0.5% bromothymol blue, 25ml
1 1.0% phenolphthalein, 25ml
1 Vinegar, 25ml
1 Household ammonia, 25ml
1 Soap solution, 25ml
1 Filtered water, 25ml
1 Vitamin C solution, 25ml
2 Wide-range pH test strips, pkg/50
1 Unknown solution #1, 25ml (Water)
1 Unknown solution #2, 25ml (Dilute base) UN1824
1 Unknown solution #3, 25ml (Phenolphthalein) UN1219
1 Unknown solution #4, 25ml (Dilute Acid)
15 Reaction trays
HS-PS1-9 (MA). Relate the strength of an aqueous acidic or basic solution to the extent of an acid or base reacting with water, as measured by the hydronium ion concentration (pH) of the solution. Make arguments about the relative strengths of two acids or bases with similar structure and composition.
Science and Engineering Practices
Mathematical and computational thinking in 9–12 builds on pre-K–8 and experiences and progresses to using algebraic thinking and analysis, a range of linear and nonlinear functions including trigonometric functions, exponentials and logarithms, and computational tools for statistical analysis to analyze, represent, and model data.
Most cells function best within a narrow range of temperature and acidity. At very low temperatures, reaction rates are too slow. High temperatures and/or extremes of acidity can irreversibly change the structure of most protein molecules. Even small changes in acidity can alter the molecules and how they interact. 5C/H7
The temperature and acidity of a solution influence reaction rates. Many substances dissolve in water, which may greatly facilitate reactions between them. 4D/M4