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Bromophenol blue is the indicator used in detecting the endpoint for the antacid analysis in this experiment. what is the expect

Paul [167]

Hello!

For the antacid analysis, the chemical reactions that occur in the titration are the following ones:

First, the antacid (composed of weak bases and carbonates) is completely neutralized by the H⁺ ions in the HCl

2HCl + CaCO₃ → CO₂ + H₂O + 2CaCl₂

HCl + OH⁻ → H₂O + Cl⁻

The titration reaction consists in titrating the excess H⁺ ions that are left in the solution, by the following reaction:

H⁺ + NaOH → H₂O + Na⁺

So, when the equivalence point is reached, the solution will go from acid to basic. As bromophenol blue is yellow in acidic solution and blue in basic solution, you'll expect the indicator to change from yellow to blue.

Have a nice day!

7 0

3 years ago

The human body excretes nitrogen in the form of urea, NH₂CONH₂. The key step in its biochemical formation is the reaction of wat

Misha Larkins [42]

Mass perventage of nitrogen in urea, arginine, ornithine is 46.67%, 32.2%,21% respectively.

What is Mass perventage ?

Mass percentage is one way of representing the concentration of an element in a compound or a component in a mixture. Mass percentage is calculated as the mass of a component divided by the total mass of the mixture, multiplied by 100.

Molecular mass of urea (NH2CONH2) is= 2× (Atomic mass of N ) + 4 × (Atomic mass of H) + (Atomic mass of C) (Atomic mass of O) = 60

Mass percentage of N = $Total mass of N atoms in the compoundMass of compound×100=2860×100=46.67%$

chemical formula for arginine is C6H14N4O2

molar mass of C6H14N4O2=174g/mol

moles of N atoms in C6H14N4O2=4

mass of N atoms=14*4=56g

mass percent of N in C6H14N4O2=(56/174)*100=32.2%

the chemical formula for ornithine is C5H12N2O2

molar mass of C5H12N2O2=132g/mol

moles of N atoms in C5H12N2O2=2

mass of N atoms in C5H12N2O2=2*14=28

mass percent of N in C5H12N2O2=(28/132)*100=21%

To learn more about urea click on the link below:

brainly.com/question/17812875

#SPJ4

7 0

1 year ago

Which choice(s) correctly rank(s) the bonds in terms of increasing polarity?

Marina CMI [18]

Answer:

(II) only correctly rank the bonds in terms of increasing polarity.

Explanation:

Bond polarity is proportional to difference in electronegativity between bonded atoms.

Atoms Electronegativity Bond Electronegativity difference

Cl 3.0 Cl-F 1.0

Br 2.8 Br-Cl 0.2

F 4.0 Cl-Cl 0

H 2.1 H-C 0.4

C 2.5 H-N 0.9

N 3.0 H-O 1.4

O 3.5 Br-F 1.2

I 2.7 I-F 1.3

Si 1.9 Cl-F 1.0

P 2.2 Si-Cl 1.1

Si-P 0.3

Si-C 0.6

Si-F 2.1

So, clearly, order of increasing polarity : O-H > N-H > C-H

So, (II) only correctly rank the bonds in terms of increasing polarity

4 0

3 years ago

Suppose that 0.250 mol of methane, CH4(g), is reacted with 0.400 mol of fluorine, F2(g), forming CF4(g) and HF(g) as sole produc

shtirl [24]

300 gallons

Explanation:

7 0

3 years ago

Write the empirical formula for at least four ionic compounds that could be formed from the following ions:

CaHeK987 [17]

Answer:

Fe(CN)₂, FeCO₃, Pb(CN)₄, Pb(CO₃)₂

Explanation:

Cations (positively charged ions) can only form ionic bonds with anions (negatively charged ions). However, you can't just simply put one cation and one anion together to form a compound. Each compound needs to been neutral, or have an overall charge of 0. When cations and anions do not have charges that perfectly cancel, you need to modify the amount of each ion in the compound.

1.) Fe(CN)₂
-----> Fe²⁺ and CN⁻

-----> +2 + (-1) + (-1) = 0

2.) FeCO₃

-----> Fe²⁺ and CO₃²⁻

-----> +2 + (-2) = 0

3.) Pb(CN)₄

-----> Pb⁴⁺ and CN⁻

-----> +4 + (-1) + (-1) + (-1) + (-1) = 0

4.) Pb(CO₃)₂

-----> Pb⁴⁺ and CO₃²⁻

-----> +4 +(-2) + (-2) = 0

5 0

2 years ago