pH of strong and weak acids and bases, mixtures

55 questions on pH of strong and weak acids and bases, mixtures from the Ionic Equilibrium I chapter: 11 NEET level, 22 JEE Main, 22 JEE Advanced. Each one opens with its answer and solution.

• The pH of a 0.01 M solution of HCl at 298 K is NEET level
• The pH of a 0.001 M solution of NaOH at 298 K is NEET level
• The pH of a 5x10^-4 M solution of Ba(OH)2 at 298 K (assume complete ionisation) is NEET level
• For a weak monobasic acid HA of concentration 0.1 M and K_a=10^-5, the pH (using [H+]=sqrtK_a c) is NEET level
• The pH of a 0.005 M solution of H2SO4 at 298 K, assuming complete ionisation of both protons, is NEET level
• The degree of ionisation of 0.1 M acetic acid (K_a=1.8x10^-5) is nearest to (use alpha=sqrtK_a/c) NEET level
• A 0.1 M solution of a weak monobasic acid has pH 3.0. Treating ionisation as small compared with c, its pK_a is NEET level
• A solution has pH 9.3 at 298 K. Its pOH is NEET level
• 10 mL of 0.1 M HCl is diluted with water to a total volume of 1000 mL. The pH of the diluted solution is NEET level
• Compared with a solution of pH 6, a solution of pH 4 has hydrogen ion concentration that is NEET level
• The pH of 0.1 M weak base BOH with K_b=10^-5 at 298 K (use [OH-]=sqrtK_b c) is NEET level
• 100 mL of 0.1 M HCl is mixed with 100 mL of 0.2 M HCl. The pH of the mixture is nearest to. Use log 2=0.301 and log 3=0.477 where needed. Take 298 K. JEE Main level
• 50 mL of 0.2 M HCl is mixed with 50 mL of 0.1 M NaOH. The pH of the resulting solution is nearest to. Use log 2=0.301 and log 3=0.477 where needed. Take 298 K. JEE Main level
• 40 mL of 0.1 M NaOH is mixed with 10 mL of 0.2 M HCl. The pH of the resulting solution is nearest to. Use log 2=0.301 and log 3=0.477 where needed. Take 298 K. JEE Main level
• The pH of 0.01 M solution of a weak acid with K_a=4x10^-6 (neglect water ionisation and use [H+]=sqrtK_ac) is. Use log 2=0.301 and log 3=0.477 where needed. Tak... JEE Main level
• The pH of 0.1 M ammonia solution (K_b=1.8x10^-5 at 298 K; use [OH-]=sqrtK_bc, log1.34=0.127) is JEE Main level
• A 0.1 M solution of a weak acid has degree of ionisation 0.01. If it is diluted to 0.025 M (assume alphall1), the new degree of ionisation is JEE Main level
• Equal volumes of 0.1 M HCl and 0.1 M acetic acid (K_a=1.8x10^-5) are mixed. The pH of the mixture is nearest to (use log5=0.699) JEE Main level
• A 0.05 M solution of a weak monobasic acid has pH 3.30. Neglecting alpha against 1, the K_a of the acid is nearest to (10^-3.30=5.01x10^-4) JEE Main level
• The concentration of ammonia solution (K_b=1.8x10^-5) that has pH 11 at 298 K is nearest to (neglect [OH-] against c) JEE Main level
• 100 mL of HCl solution of pH 2 is mixed with 100 mL of HCl solution of pH 4. The pH of the mixture is nearest to (use log5.05=0.703) JEE Main level
• 300 mL of NaOH solution of pH 12 is mixed with 100 mL of HCl solution of pH 2 at 298 K. The pH of the mixture is nearest to (use log5=0.699) JEE Main level
• Calculate the pH of 0.04 M Ba(OH)2 solution at 298 K, assuming complete ionisation. Give the answer to two decimal places. JEE Main level
• What volume of water (in mL) must be added to 100 mL of HCl solution of pH 2 to change its pH to 3? Give the answer to the nearest integer. JEE Main level
• Find the percentage ionisation of 0.2 M acetic acid (K_a=1.8x10^-5) using alpha=sqrtK_a/c. Give the answer to two decimal places. JEE Main level
• A 0.1 M solution of a weak monobasic acid is 1.5% ionised. Using K_a=calpha^2/(1-alpha), calculate K_ax10^5 to two decimal places. JEE Main level
• 150 mL of 0.2 M HCl is mixed with 100 mL of 0.25 M NaOH. Calculate the pH of the mixture (298 K) to two decimal places. JEE Main level
• 1 L of NaOH solution of pH 10 is mixed with 1 L of NaOH solution of pH 13 at 298 K. Find the pH of the mixture to two decimal places. JEE Main level
• Ammonia solution has pH 10.5 at 298 K. With K_b=1.8x10^-5 and neglecting [OH-] against the total concentration, calculate its concentration c as cx10^3 in mol L... JEE Main level
• A 0.1 M solution of a weak monobasic acid has K_a=1.0x10^-3. Solving the quadratic x^2+K_ax-K_ac=0 exactly (no approximation), find the pH to two decimal places... JEE Main level
• Equal volumes of 0.1 M HCl and 0.1 M acetic acid (K_a=1.8x10^-5) are compared (separate solutions, 298 K). Select the correct statement(s). JEE Main level
• A 0.1 M solution of a weak monobasic acid HA (K_a=10^-5) is diluted to 0.001 M at 298 K. Select the correct statement(s). JEE Main level
• Consider P: 0.01 M HCl; Q: 0.005 M H2SO4; R: 0.01 M NaOH; S: 0.005 M Ba(OH)2 (all strong, fully ionised, 298 K). Select the correct statement(s). (Use log 5=0.6... JEE Main level
• 100 mL of 0.1 M acetic acid (K_a=1.8x10^-5) is mixed with 100 mL of 0.1 M HCl. The degree of ionisation of acetic acid in the mixture is nearest to JEE Advanced level
• 50 mL of 0.2 M NH3 (K_b=1.8x10^-5) is mixed with 50 mL of 0.002 M NaOH. Taking the ammonia ionisation in presence of the strong base into account, the pH of the... JEE Advanced level
• 200 mL of 0.05 M HCl is mixed with 300 mL of 0.1 M acetic acid (K_a=1.8x10^-5). The pH of the mixture is nearest to (use log2=0.301) JEE Advanced level
• 100 mL of 0.2 M HA (K_a=1.0x10^-5) is mixed with 100 mL of 0.2 M HB (K_a=4.0x10^-5). Both are weak monobasic acids. Using [H+]=sqrtK_1c_1+K_2c_2, the pH of the ... JEE Advanced level
• The pH of 1.0x10^-8 M HCl at 298 K is nearest to JEE Advanced level
• At a certain temperature K_w=4.0x10^-14. The pH of 0.02 M NaOH at that temperature is nearest to (use log2=0.301) JEE Advanced level
• A weak monobasic acid in 0.1 M solution has pH 3.00 (so K_a may be taken as 1.0x10^-5). Solving the quadratic exactly, the pH of its 0.001 M solution is nearest... JEE Advanced level
• Equal volumes of an HCl solution of pH 2.00 and a NaOH solution of unknown pH are mixed, and the resulting solution has pH 3.00 at 298 K. The pH of the NaOH sol... JEE Advanced level
• What volume (in mL) of 0.1 M NaOH must be added to 100 mL of 0.2 M HCl so that the pH of the final solution is exactly 2.00? Give the answer to the nearest inte... JEE Advanced level
• A weak monobasic acid (K_a=2.0x10^-5) is 2.5% ionised in a certain solution. This solution is diluted with water to four times its original volume. Using the ex... JEE Advanced level
• 200 mL of 0.05 M H2SO4 (both protons fully ionised) is mixed with 300 mL of 0.1 M NaOH and 100 mL of water. Calculate the pH of the final solution at 298 K to t... JEE Advanced level
• 100 mL of HCl of pH 1, 200 mL of HCl of pH 2 and 100 mL of 0.05 M NaOH are mixed. Find the pH of the mixture to two decimal places. JEE Advanced level
• Find the pH of 4.0x10^-7 M NaOH at 298 K, taking the ionisation of water into account (solve the resulting quadratic exactly). Give the answer to two decimal pl... JEE Advanced level
• 100 mL of 0.2 M ammonia (K_b=1.8x10^-5) is mixed with 100 mL of 0.2 M of another weak base (K_b=3.0x10^-6). Using [OH-]=sqrtK_1c_1+K_2c_2 with the concentration... JEE Advanced level
• A 0.1 M solution of a weak monobasic acid (K_a=1.0x10^-5) is diluted to 0.025 M at 298 K (use alphall1, log2=0.301). Select the correct statement(s). JEE Advanced level
• 100 mL of HCl of pH 1 is mixed with 400 mL of HCl of pH 3. Select the correct statement(s). (Use log2.08=0.318.) JEE Advanced level
• 100 mL of 0.3 M HCl is mixed with 200 mL of 0.1 M NaOH at 298 K. Use log3=0.477. Select the correct statement(s). JEE Advanced level
• For 0.1 M ammonia solution (K_b=1.8x10^-5 at 298 K; log1.34=0.127, use [OH-]=sqrtK_bc), select the correct statement(s). JEE Advanced level
• Two separate 0.1 M solutions of weak monobasic acids HA (K_a=10^-5) and HB (K_a=10^-7) are prepared at 298 K. Select the correct statement(s). (Use alphall1.) JEE Advanced level
• At 373 K, take K_w=1.0x10^-12. Select the correct statement(s). JEE Advanced level
• Which statement(s) about dilution of strong base NaOH at 298 K is/are correct? (Solve exactly with water ionisation when needed; give pH to two decimals.) JEE Advanced level
• Equal volumes of 0.1 M HCl and 0.1 M HA (K_a=1.0x10^-5) are mixed at 298 K (use log5=0.699). Select the correct statement(s). JEE Advanced level