COMPERATIVE STUDY OF THE EFFECT OF SODIUM HYDROXIDE ON PH LEVEL OF CITRIC ACID IN LEMON JUICE IN FOUR COMMUNITIES IN YALA L.G.A

This study investigates the pH and acidity levels of lemon juice samples from four locations— Okpoma, Okuku, Ugaga, and Yahe—along with their titration behavior. Juice samples obtained from the four locations were assigned unique group codes for proper identification: Group A (Okpoma), Group B (Okuku), Group C (Ugaga) and Group D (Yahe). For each group, juice samples were prepared in triplicate (n=3) and analyzed for pH determination and neutralization using 0.20 N NaOH under controlled room temperature condition. The pH values ranged from 2.29+0.02 (Okpoma) to 2.55+0.01 (Yahe), with all samples classified as highly acidic due to their citric acid content (5-6%). Statistically significant pH differences, likely due to variations in lemon cultivars, soil pH, or growing conditions, suggest potential implications for culinary, industrial, and pharmaceutical applications. Additionally, titration of a 5.00 mL lemon juice sample with 0.20 N NaOH revealed a characteristic curve with buffering regions and a sharp pH increase at the equivalence point, reflecting the polyprotic nature of citric acid (pKa values: 3.13, 4.76, 6.40). These findings suggest that citric acid and related weak organic acids are the primary contributors to lemon juice acidity, with neutralization pathways demonstrating predictable acidbase interactions.