Question

In: Biology

WHICH OF THE FOLLOWING REACTIONS REPRESENTS A STRONG ACID? A. HCl ---> H+ +Cl- B. NH3...

WHICH OF THE FOLLOWING REACTIONS REPRESENTS A STRONG ACID?

A. HCl ---> H+ +Cl-

B. NH3 + H+ <-----> NH4+

C. H2CO3 <----> HCO3- + H+

D. NaOH ---> Na+ +OH-

A solution has a pH of 1.0 x 10^(-2)M. What best describes the solution?

BASIC

ACIDIC

SALTY

NEUTRAL

Solutions

Expert Solution

(1) (A) is the correct answer.

Acid is a substance that releases H+ ions in water and base is a substance that takes up hydrogen ions present in a solution.

A strong acid is one which dissociates completely in water. Dissociation refers to breaking down to produce H+ ions.

Also, a strong acid produces a weak conjugate base(the ion produced after acid dissociation along with H+ ion). A weak base is one which do not accept proton from H3O+; i.e, the reverse reaction does not occur.

Strong acids release all H+ ions in them, whereas weak acids do not release all the H+ions.

In option (A), HCl dissociates completely releasing H+ and Cl- ions. All HCl molecules dissociate completely in solution.

Cl- is the conjugate base that do not accept H+ readily. So, HCl is a strong acid.

In (B), NH3 accepts an H+ and forms NH4+ ion.

Since NH3(ammonia) accept H+ ions, it is a base.

In(C), H2CO3 do not dissociate completely; it releases only one H+ ion and HCO3- ion.

A weak acid produces a strong conjugate base; meaning that the base has high affinity for H+ and reverse reaction takes place.

HCO3- easily accepts proton; therefore it is a strong conjugate base making H2CO3 a weak acid.

In (D), NaOH dissociates completely into Na+ and OH- in aqueous solution. OH- is the conjugate acid formed here; it has reduced tendency to donate protons and therefore is a weak conjugate acid making NaOH a strong base.

(2)(B) is the correct answer.

Given that the H+ ion concentration[H+] of the solution is 1.0×10^(-2)M.

The value of pH for a solution helps to determine whether a given solution is acidic, basic, or neutral.

Salts can also be acidic, basic or neutral. The pH of salt solutions is also determined in the same manner.

A pH scale ranges from 1 to 14.

A solution with pH of 7 is neutral;value less than 7 is acidic and a value above 7 shows that the solution is basic.

The pH of a solution with known concentration of H+ ions is calculated as follows:

pH = -log[H+]

pH = -log[1.0× 10^(-2)]

pH = -log[10^(-2)]

pH = -(-2)

pH = 2

So, the pH of the given solution is 2; indicating that the solution is acidic.

We cannot determine whether a solution is salty from its pH value.


Related Solutions

25.0 mL of a 0.100 M NH3 is titrated with a strong acid. 0.100 M HCl....
25.0 mL of a 0.100 M NH3 is titrated with a strong acid. 0.100 M HCl. Calculate the pH of the NH3 solution at the following points during the titration: (Kb= 1.8 x 10^-5) A. Prior to the addition of any HCl. B: After the addition of 10.5 mL of a 0.100 M HCl. C: At the equivilance point. D: After the addition of 3 mL of 0.100 M HCl. Show your work.
Consider the titration of 0.100 M HCl, a strong acid, with 0.100 M NH3, a weak...
Consider the titration of 0.100 M HCl, a strong acid, with 0.100 M NH3, a weak base: HCL(aq)+NH3(aq)---NH4+(aq)+H2O(l) Calculate the pH at the following points in the titration when 25.0 mL of 0.0100 M NH3 is titrated with 0.100 M HCL. A. 0.0 mL of HCl added B. 10.0 mL of HCl added C. At equivalence point D. 35.0 mL of HCL added
A. What was the ?H value obtained for NH3 + HCl
A. What was the ?H value obtained for NH3 + HCl
4. In the covalent compaound HCL, H-Cl, or H:Cl, which element has the greater electronegativity? __________...
4. In the covalent compaound HCL, H-Cl, or H:Cl, which element has the greater electronegativity? __________ The shared electrons should be closer to ________. 3. Of the following pH values, which indicates a weak basic solution? a.) 2.7         b.) 8.3         c.) 4.2       d.) 10.8        e.) 14.0 A. Dissociation of Water Molecules H2O + H2O -----------------> H3O^+ + OH^-                   <---------------- B. Acids and Bases At equilibrium in pur water at 25 degrees Celsius, the number of H+ ions = number...
Which of the following compounds has the highest pka? a. NH3 b. H2O c. HCl d....
Which of the following compounds has the highest pka? a. NH3 b. H2O c. HCl d. CH4
consider the titration of a strong acid, HCL, with a strong base NaOH. The 35 ml...
consider the titration of a strong acid, HCL, with a strong base NaOH. The 35 ml of .1 M HCL is in the flask. What is the pH of the solution after 40 ml of .100 M NaOH has been added to to it?
Which of the following compounds is a Lewis acid? a. BCl3 b. NH3 c. CH4 d....
Which of the following compounds is a Lewis acid? a. BCl3 b. NH3 c. CH4 d. CHCl3
For which of the following reactions is Δ H ∘ rxn equal to Δ H ∘...
For which of the following reactions is Δ H ∘ rxn equal to Δ H ∘ f of the product(s)? You do not need to look up any values to answer this question. Check all that apply. Check all that apply. BaC O 3 (s)→BaO(s)+C O 2 (g) C(s,graphite)+ O 2 (g)→C O 2 (g) CO(g)+ 1 2 O 2 (g)→C O 2 (g) 2Na(s)+ F 2 (g)→2NaF(s) Na(s)+ 1 2 F 2 (l)→NaF(s) Na(s)+ 1 2 F 2 (g)→NaF(s)...
Which of the following bonds are polar: C-Se, C-O, Cl-Cl, O=O, N-H, C-H? In the bond...
Which of the following bonds are polar: C-Se, C-O, Cl-Cl, O=O, N-H, C-H? In the bond or bonds that you selected, which atom has the greater electronegativity?
Which of the following is the conjugate acid of H2S? Select one: a. H3S+ b. H+...
Which of the following is the conjugate acid of H2S? Select one: a. H3S+ b. H+ c. H2SO4 d. HS- e. S Which of the following is a weak acid? Select one: a. salicylic acid b. hydrochloric acid c. sulfuric acid d. hydrobromic acid e. nitric acid Which of the following is the conjugate base of H2S? Select one: a. SO2 b. S c. OH- d. SH- e. H3S+ If the [H+] = 1.0 x 10-9, what is the pH?...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT