1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
alexira [117]
3 years ago
10

What is the ph of a soft drink in which the major buffer ingredients are 6.6 g of nah2po4 and 8.0 g of na2hpo4 per 355 ml of sol

ution?
Chemistry
1 answer:
Alex777 [14]3 years ago
5 0
The Relative Formula Mass of NaH2PO4 is 120 g/mol
Therefore, the number of moles = 6.6/120
                                                   = 0.055 moles of NaH2PO4 which is also equal to the number of moles of H2PO4.
[H2PO4-] = Number of moles oof H2PO4-/Volume of the solution in L
  = 0.055/ ( 355 ×10^-3)
  = 0.155 M
Na2HPO4 undergoes complete dissociation as follows;
Na2HPO4 (aq)= 2Na+ (aq) + HPO4^2- (aq)

1 mole of Na2HPO4 = 142 g/mol
Therefore; number of moles = 8.0/142
                                             = 0.0563 moles
 [HPO4 ^-2] is given by no of moles HPO4^2- /volume of the solution in L
     = 0.0563/(355×10^-3)
     =  0.1586 M
Both H2PO4^2- and HPO4^2- are weak acids the undergoes partial dissociation 
Ka of H2PO4- = 6.20 × 10^-8
 [H+] =Ka*([H2PO4-]/[HPO4(2-)]
        = (6.20 ×10^-8)×(0.155/0.1586)
        = 6.059 ×10^-8 M
pH = - log[H+]
     = - log (6.059×10^-8)
     = 7.218

You might be interested in
A NaOH (aq) stock solution was created by dissolving 3.88 g NaOH in water to create a 100.00 mL solution. What is the concentrat
Ierofanga [76]

Answer:

I have don 3 so far

Explanation:

Brainlyis the best

8 0
2 years ago
Write a net ionic equation for the overall reaction that occurs when aqueous solutions of sodium hydroxide and hydrosulfuric aci
Helga [31]

Answer:

2OH-(aq) + 2H+(aq) → 2H2O(l)

Explanation:

Step 1: Data given

sodium hydroxide = NaOH

hydrosulfuric acid = H2S

Step 2: The unbalanced equation

NaOH(aq) + H2S(aq) → Na2S(aq) + H2O(l)

Step 3: Balancing the equation

On the left side we have 1x Na (in NaOH), on the right side we have 2x Na (in Na2S). To balance the amount of Na on both sides, we have to multiply NaOH on the left side by 2.

2NaOH(aq) + H2S(aq) → Na2S(aq) + H2O(l)

On the left side we have 4x H (2x in NaOH and 2x in H2S), on the right side we have 2x H (in H2O). To balance the amount of H on both sides, we have to multiply H2O on the right side by 2. Now the equation is balanced.

2NaOH(aq) + H2S(aq) → Na2S(aq) + 2H2O(l)

Step 4: The net ionic equation

2Na+(aq) + 2OH-(aq) + 2H+(aq) + S^2-(aq) → 2Na+(aq) + S^2-(aq) + 2H2O(l)

The net ionic equation, for which spectator ions are omitted - remember that spectator ions are those ions located on both sides of the equation - will , after canceling those spectator ions in both side, look like this:

2OH-(aq) + 2H+(aq) → 2H2O(l)

8 0
3 years ago
How many fluorine atoms bond with calcium to form calcium fluoride? one two three four five
Elena-2011 [213]
Calcium fluoride.
Ca is metal, F is non-metal, so they form ionic bond.
Ca as metal can form only positive ion. Ca in the second group, so the charge of Ca ion is 2+.   Ca²⁺
F is in the 17th group, so it has 7 electrons on the last level. It is non-metal, non-metal, so it has negative charge -(8-7)=-1. "8" because on the last level cannot be more than 8 electrons. F-ion is F¹⁻.

Ca²⁺  F¹⁻
Number of positive charges should be equal to number of negative charges,
Formula of calcium fluoride
CaF2.
2 atoms Fluorine bond with Calcium.
7 0
3 years ago
Which of the following sets of empirícal formula, molar mass, and molecular formula is correct?
skad [1K]

<em>Answer:</em>

  • The option C is correct.
  • CH4N, 90g, C3H12N3.

<em>Explanation:</em>

                    <em>Option C:</em>

  • The molecular formula is C3H12N3.
  • If we take ratio 3:12:3 that will be equal to 1:4:1 so its empirical formula will be CH4N.
  • The molar mass of molecular formula = (12×3) + (1×12) +( 14×3) = 98 g

                <em>Option A :</em>

  • In option A , molecular and empirical formula are both correct but molar mass is not valid. It should be 169 acc. to molecular formula.

              <em>Option B:</em>

  • In option B, molecular formual is not valid.
  • It should be as C6H16O2
4 0
3 years ago
Besides two molecules of pyruvate, what are the net products of glycolysis?
navik [9.2K]
The answer is 2 ATP and 2 NADH.
5 0
2 years ago
Other questions:
  • Pyridoxine contains 11 hydrogen atoms, 8 carbon atoms, 3 oxygen atoms, and 1 nitrogen atom. what is the chemical formula for pyr
    12·1 answer
  • Nitrogen and hydrogen combine to form ammonia in the Haber process. Calculate (in kJ/mole) the standard enthalpy change DH° for
    13·2 answers
  • Normally the systemic arterial blood has a po2 of about _____ mm hg, a pco2 of about _____ mm hg, and a ph of _____.
    13·1 answer
  • Dry ice (solid CO2) has occasionally been used as an "explosive" in mining. A hole is drilled, dry ice and a small amount of gun
    14·1 answer
  • How does radioactivity make it possible to understand how earth can be so old and still have a hot interior?
    14·2 answers
  • The first step in creating a network is building a(n) _____.
    7·2 answers
  • Density is calculated by solving for a mass divided by ______
    6·1 answer
  • Electrons in atoms exist in particular energy level. A ___ must be emitted or absorbed to move between energy levels.
    13·1 answer
  • Which of the following is the correct chemical formula for cs and br? csbr cs2br csbr2
    10·2 answers
  • PLEASE ANSWER QUESTION 6!!
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!