According to Raoult's low:
We will use this formula: Vp(Solution) = mole fraction of solvent * Vp(solvent)
∴ mole fraction of solvent = Vp(Solu) / Vp (Solv)
when we have Vp(solu) = 25.7 torr & Vp(solv) = 31.8 torr
So by substitution:
∴ mole fraction of solvent = 25.7 / 31.8 =0.808
when we assume the moles of solute NaCl = X
and according to the mole fraction of solvent formula:
mole fraction of solvent = moles of solvent / (moles of solvent + moles of solute)
by substitute:
∴ 0.808 = 0.115 / (0.115 + X)
So X (the no.of moles of NaCl) = 0.027 m
Answer:
The new temperature of the water bath 32.0°C.
Explanation:
Mass of water in water bath ,m= 8.10 kg = 8100 g ( 1kg = 1000g)
Initial temperature of the water = ![T_1=33.9^oC=33.9+273K=306.9 K](https://tex.z-dn.net/?f=T_1%3D33.9%5EoC%3D33.9%2B273K%3D306.9%20K)
Final temperature of the water = ![T_2](https://tex.z-dn.net/?f=T_2)
Specific heat capacity of water under these conditions = c = 4.18 J/gK
Amount of energy lost by water = -Q = -69.0 kJ = -69.0 × 1000 J
( 1kJ=1000 J)
![Q=m\times c\times \Delta T=m\times c\times (T_2-T_1)](https://tex.z-dn.net/?f=Q%3Dm%5Ctimes%20c%5Ctimes%20%5CDelta%20T%3Dm%5Ctimes%20c%5Ctimes%20%28T_2-T_1%29)
![-69.0\times 1000 J=8100 g\times 4.18 J/g K\times (T_2-306.9 K)](https://tex.z-dn.net/?f=-69.0%5Ctimes%201000%20J%3D8100%20g%5Ctimes%204.18%20J%2Fg%20K%5Ctimes%20%28T_2-306.9%20K%29)
![-69,000.0 J=8100 g\times 4.18 J/g K\times (T_2-306.9 K)](https://tex.z-dn.net/?f=-69%2C000.0%20J%3D8100%20g%5Ctimes%204.18%20J%2Fg%20K%5Ctimes%20%28T_2-306.9%20K%29)
![T_2=304.86 K=304.86 -273^oC=31.86^oC\approx 32.0^oC](https://tex.z-dn.net/?f=T_2%3D304.86%20K%3D304.86%20-273%5EoC%3D31.86%5EoC%5Capprox%2032.0%5EoC)
The new temperature of the water bath 32.0°C.
Answer:
All atoms of the same element have always have the same amount of protons.
Explanation:
Atoms of the same element have always have the same amount of protons but not always the same electrons and neutrons. If an atom gains or loses one of its valance electrons, the electrons on the outermost shell, then it becomes ionized. Also not all atoms of the same element have the same amount of neutron. This is called an isotope. A good example would be Carbon 13. Normally, Carbon atoms have an atomic mass of 12 AMU or 12 atomic mass units. However, Carbon atoms have an atomic mass of 13 AMU, consisting of 7 neutrons instead of 6 neutrons. So the only thing that all atoms of the same element have in common is the amount of protons.
Answer:
For H3O concentration you do 10^-pH so if pH is 5 then H3O+ is 10^-5= 1*10^-5 H3O+ ions
For OH is one extra step. First find H3o+ ions using equation above then you have to use that to divide 1*10^-14
So if pH is 5....the H3O+ is 1*10^-5 then OH- = (1*10^-14)/(1*10^-5) = 1*10^-9 OH ions
as far as acid/base pH 0-6 is Acid 8-14 is Base. pH of 7 is neutral. Recheck your work *hint* *hint* water is neutral. Spit is above 7 so is base.
<h3>The <u>
complete question</u>
would be:</h3>
In a common laboratory experiment in general chemistry, students are asked to determine the relative amounts of benzoic acid and charcoal in a solid mixture. Benzoic acid is relatively soluble in hot water, but charcoal is not. Devise a method for separating the two components in the mixture.
<h3>The <u>
solution</u> for that would be:</h3>
First you put the mixture in hot water and allow the benzoic acid to separate. Next funnel it and then see what's on the funnel paper. Lastly, heat the leftover water and see what's left after it evaporates.
<h3><u>What are laboratory experiments ?</u></h3>
- Using controlled surroundings to test theories, researchers may develop laboratory experiments.
- Laboratories are rooms or specially constructed facilities within buildings that are often found on college and university campuses and are utilized for academic research.
- It's crucial to differentiate between experiments and other kinds of research investigations carried out in lab settings.
- Even if a research study takes place in a lab, it is not always an experiment.
- In order to evaluate causal conclusions regarding the links between independent and dependent variables, laboratory studies, like all genuine experimental designs, use procedures of random assignment of participants and control groups.
To view more about experiments, refer to:
brainly.com/question/17143317
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