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4 years ago

Ejercicios sobre análisis gravimétrico y análisis volumétrico.

1 answer:

7 0

1) Answer is: pH = 3,44.
c(H₃O⁺) = 3,6·10⁻⁴ M = 3,6·10⁻⁴ mol/L = 0,00036 mol/L.
pH = -logc(H₃O⁺).
pH = -log(0,00036 mol/L).
pH = 3,44.
When pH is less than seven (pH<span><), solution is acidic (like this example).
</span>When is equal seven (pH = 7), solution is neutral.
When pH is greater than seven (pH <span>> 7), solution is basic.
</span>
2) Answer is: volume of H₂SO₄ is 5,75 mL.
Chemical reaction: H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O.
c(H₂SO₄) = 0,2 M = 0,2 mol/L.
V(NaOH) = 23 mL = 0,023 L.
c(NaOH) = 0,1 M = 0,1 mol/L.
n(NaOH) = c(NaOH) · V(NaOH).
n(NaOH) = 0,1 mol/L · 0,023 L.
n(NaOH) = 0,0023 mol.
From chemical reaction: n(H₂SO₄) : n(NaOH) = 1 : 2.
n(H₂SO₄) = 0,00115mol.
V(H₂SO₄) = n(H₂SO₄) ÷ c(H₂SO₄).
V(H₂SO₄) = 0,00115 mol ÷ 0,2 mol/L.
V(H₂SO₄) = 0,00575 L = 5,75 mL.

3) c₁(solution) = 0,011 M = 0,011 mol/L.
V₁(solution) = 800 mL = 0,8 L.
M(methylene blue - C₁₆H₁₈ClN₃S) = 319,85 g/mol.
n₁ = c₁ · V₁.
n₁ = 0,011 mol/L · 0,8 L.
n₁ = 0,0088 mol.
m(C₁₆H₁₈ClN₃S) = 0,0088 mol · 319,85 g/mol.
m(C₁₆H₁₈ClN₃S) = 2,814 g.
m(C₁₆H₁₈ClN₃S) = 2,814 g · 1000mg/g = 2814 mg.
V = n ÷ c
V₂ = 0,0088 mol ÷ 0,001 mol/L = 8,8 L = 8800 mL.
V₃ = 0,0088 mol ÷ 0,00075 mol/L = 11,73 L = 11730 mL.

4) The normality or the equivalent concentration:
Cn(KH₂PO₄) = 0,02 N = 0,02 eq/L (<span>equivalent per liter).
</span>V(KH₂PO₄) = 0,125 L.
number of equivalents of solute = Cn(KH₂PO₄) · V(KH₂PO₄).
number of equivalents of solute = 0,02 eq/L · 0,125 L.
number of equivalents of solute = 0,0025 eq.
equivalent weight = M(KH₂PO₄) ÷ number of equivalents per mole of solute.
equivalent weight = 136,1 g/mol ÷ 1 eq/mol.
equivalent weight = 136,1 g/eq.

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Paha777 [63]

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3 years ago

Calcium carbonate interacts with omadacycline (Nuzyra). How should this interaction be avoided?(Interactions) hint look up omada

stellarik [79]

Answer: An interaction is caused between the two medications (Calcium carbonate and Omadacycline) and causes serious negative side effects, due to the fact that when the two are taken together the body is unable to process the antibiotic therefore causing a reduction in the concentration of antiobiotics in the blood stream. this causes a reduction the body's ability to fight off the infection. In addition, drug interactions with calcium increase the risk of dangerously high calcium levels in the blood and disrupt the body´s basal state.

Explanation:

Omadacycline is a broad spectrum antibiotic. It belongs to the tetracycline group and specifically to the aminomethylcycline subclass and is used mainly in the treatment of treatment of community-acquired bacterial pneumonia and acute skin and skin structure infections. the mecanism of action of Omadacycline works like every other tetracycline antiobiotic. It inhibits the bacterial protein synthesis thereby rendurig the bacteria useless and thus stopping the replicaton of these bacterias.

Calcium carbonate on the other hand, is usuallly administered as a dietary supplement when the corporal levels of calcium do not reach sufficient levels. It may also be used as an antacid to relieve heartburn, acid indigestion, and nausea. It is available with or without a prescription and is available in many forms for example; as a tablet, chewable tablet, capsule or as a liquid.

Calcium is vital for healthy bones, muscles, nervous system, and heart. Calcium is involved in cardiac muscle contraction and electrical impulse conduction.

When calcium carbonate is taken with Omadacycline causes a significant increase in the levels of calcium in the blood. Excess levels of calcium interfere with the absorption of the antibiotic because calcium binds to the tetracycline in the intestine causing a reduction in the efectiveness. Failure to control the infection could lead to severe side effects whether temporary or permanent and in extreme cases death.

<h3>Calcium carbonate SHOULD NOT BE TAKEN WITH </h3>

Bisphosphonates
Fluoroquinolone antibiotics
H2 blockers
Proton pump inhibitors (PPIs)
Tetracycline antiobiotics (Omadacycline- Nuzyra)
Thiazide diuretics

In conclusion, calcium carbonate should not be taken with tetracycline antiobiotics in this case Omadacycline because it causes an ncrease in calcium levels which binds to the antibiotic therefore reducing its absorption by the intestine and reducing its effect in fighting off the infection. The antiobiotic should be taken two hours before the calcium carbonate or about four to six hours after.

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3 years ago

Explain how you can determine the number of neutrons in the nucleus of an atom of any of the elements listed in the table.

daser333 [38]

Different explanations that lead to the same result

-You need to substract the number of protons from the mass number.

-Mass number - atomic number= number of protons

-Following this equation:

CARBON

atomic number= 6

mass number= 12

mass number= protons + neutrons

12= 6 + x

x= 12-6

x= 6

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3 years ago

Scientific inquiry attempts to search out, describe, explain, and predict things that happen in nature. Which of the following b

alexdok [17]

<span>By asking questions and collecting, analyzing, and interpreting data to answer them</span>

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4 years ago

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The c—c—c bond angle in propane, c3h8, is closest to

Archy [21]

Propane has a molecular formula C3H8.

It is of the form CnH2n+2.
where n = number of C atoms. In present case n = 3.

Each carbon atom in propane is sp3 hydribized. Thus, there are 4 hydrid orbital associated with each carbon atom

The central C atom is sigma bonded to two other carbon atoms and two hydrogen atoms.

Such, sp3 hydridized orbitals are spacial orientated at an angle of $109^{0}28^{'}$ , in order to minimize repulsion between the electrons.

Hence, the c—c—c bond angle in propane, c3h8, is closest to $109^{0}28^{'}$

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4 years ago

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