Answer:
0.38
Explanation:
Molar mass of thiophene= 84g/mol
Mass of thiophene = 37g
Number of moles= 37/84= 0.44 moles
Molar mass of heptane= 100 g/mol
Mass of heptane = 72g
Number of moles = 72/100= 0.72 moles
Total number of moles= 0.44 + 0.72= 1.16 moles
mole fraction of thiophene = 0.44/1.16= 0.38
Neutralization reaction is the reaction between acid and base.
There the neutralization reaction is:
HBr + LiOH ----------> LiBr + H2O.
Hope this helps!
I’m pretty sure it’s A sorry if wrong
Light acting as 'packets' of exact amounts of energy (a particle-like quality) called quanta led to the development of quantum mechanics. Light also has wave qualities (wavelength, frequency, amplitude) which is referred to as particle-wave duality.
Considering the definition of percentage by mass, the mass percentage of CaCO₃ is 68.59%.
<h3>What is mass percentage</h3>
The percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.
In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.
The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:

<h3>Mass percentage of CaCO₃</h3>
In this case, you know:
- mass of CaCO₃: 2.62 grams
- mass of limestone: 3.82 grams
Replacing in the definition of mass percentage:

<u><em>mass percentage= 68.59 %</em></u>
Finally, the mass percentage of CaCO₃ is 68.59%.
Learn more about percentage by mass:
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