Magnesium trisilicate, Mg2Si3O8·H2O in medicine is an antacid. Explain the use of magnesium silicate as an antacid to reduce acidity in the stomach. Give the equation of reaction. For titration of 5 ml of gastric juice, 10 ml of a 0.15 M sodium hydroxide solution were used. Does the patient need to take Mg2Si3O8·H2O (The concentration of hydrochloric acid in the stomach of a healthy person is constant and amounts to 160 mmol/L)?

43.  A buffer is prepared using acetic acid, CH3COOH, (a weak acid, pKa = 4.75) and sodium acetate, CH3COONa (which provides acetate ions, the conjugate base), according to the following proportions:   Volume of CH3COOH(aq):   125.0 mL Concentration of CH3COOH(aq):  1.263 M   Volume of CH3COONa(aq):  106.0 mL Concentration of CH3COONa(aq):  1.279 M   Determine the volume of 6.00 M HCl required to change the pH of this buffer by one pH unit.       18.15 mL     36.30 mL     21.87 mL     19.30 mL     43.73 mL

7.7 g of citric acid (MM = 192.1 g/mol) can be titrated with NaOH according to the following balanced chemical equation.           H3C6H5O7  (aq) + NaOH(aq) → H2O(l) + Na H2C6H5O7(aq) what would the curve for the titration of the neutralization of the three hydrogens of this acid with NaOH look like?

7 (a) Describe what happens when each of the following molecules is separately dissolved in water and illustrate with an equation in each case: (i) ethanoic acid (CH₂COOH) (ii) ammonia (NH3) (b) Identify the conjugate acids and bases in the substances mentioned in question 7(a) above. (c) Explain the difference between: (i) a strong acid and weak acid and (ii) a strong base and a weak base

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What is the general equation given when examining a titration? O A (aq) + H20 (1) = HA + OH (aq) (aq) H*e (aq) + ОН (aq) + OH' = H2O (1) О НА (aq) + H20 () =A (aq) + H3O*(aq) O HA (ag) + NaOH (ag) = NaA (aq) + H2O (1)

A student added 1.78g of Ca(OH)2(9) to 0.250 L of 0.200 molL-1 HNO3(aq)- The mixture was carefully stirred until no further reaction occurred. Assuming that the total volume of the solution remains unchanged, calculate the pH of the resulting solution.

Zn(II) hydroxide is amphoteric (amphiprotic). Complete and balance the following equations. Include the phases of all species in the chemical equations. Complete and balance a chemical equation showing how an aqueous suspension of this compound reacts to the addition of a strong acid. Zn(OH)2​(s)+2H+(aq)   Complete and balance a chemical equation showing how an aqueous suspension of this compound reacts to the addition of a strong base.   Zn(OH)2​(s)+2OH−(aq)

42. A buffer is prepared using acetic acid, CH3COOH, (a weak acid, pKa = 4.75) and sodium acetate, CH3COONa (which provides acetate ions, the conjugate base), according to the following proportions:   Volume of CH3COOH(aq):   139.0 mL Concentration of CH3COOH(aq):  1.103 M   Volume of CH3COONa(aq):  127.0 mL Concentration of CH3COONa(aq):  1.259 M   Calculate the pH of this buffer after the addition of 20.00 mL of 3.00 M sodium hydroxide, NaOH, a strong base.     4.38     5.90     4.69     4.81     5.12

What is the pH of a 0.15M NH4C1 (aq) solution given ammonia has a Kp of 1.8 x 10°