Answer:
Nitrogen gas (N2) should have the lowest boiling point among the given options. This is because N2 is a nonpolar molecule with weak London dispersion forces between its molecules, which results in a relatively low boiling point. Sodium sulfide (Na2S) is an ionic compound, so it has a very high boiling point due to strong electrostatic forces between its ions. Ammonia (NH3) and hydrogen fluoride (HF) are polar molecules that can form hydrogen bonds between their molecules, which results in higher boiling points than N2.
Explanation:
Nitrogen gas (N2) should have the lowest boiling point among the given options. This is because N2 is a nonpolar molecule with weak London dispersion forces between its molecules, which results in a relatively low boiling point. Sodium sulfide (Na2S) is an ionic compound, so it has a very high boiling point due to strong electrostatic forces between its ions. Ammonia (NH3) and hydrogen fluoride (HF) are polar molecules that can form hydrogen bonds between their molecules, which results in higher boiling points than N2.
Determine whether the study is experiment or an observational study, and then identify a major problem with the study. a) The Physicians Health Study involved 22,071 male physicians. Based on random selections, 11,037 of them were treated with aspirin and the other 11,034 were given placebos. The study was stopped early because it became clear that the aspirin reduced the risk of hear attack by a substantial amount. b) A medical researcher tested for a difference in systolic blood pressure levels between male and female students who are 12 years of age. She randomly selected four males and four females for her study.
a) The study is an experimental study.
A major problem with the study is the lack of blinding.
b) The study is an observational study.
A major problem with the study is the small sample size.
a) The Physicians Health Study is an experiment because the researchers intentionally assigned participants to two groups: one receiving aspirin and the other receiving placebos.
A major problem with the study is the lack of blinding. Since the participants were aware of whether they were receiving aspirin or placebos, their knowledge could have influenced their behavior and responses, potentially introducing bias. Additionally, the study involved only male physicians, so the results may not be generalizable to other populations or genders.
b) The study described is an observational study because the researcher did not intervene or assign treatments. Instead, the researcher observed and compared existing differences in systolic blood pressure levels between male and female students.
A major problem with the study is the small sample size. With only four males and four females, the sample may not be representative of the larger population, limiting the generalizability of the findings. Additionally, the study did not specify any control or comparison group, making it challenging to draw definitive conclusions about the differences in blood pressure between genders.
Learn more about experimental study
https://brainly.com/question/3233616
#SPJ11
A given ample of ga ha a volume of 4. 20 L at 60. C and 1. 00 atm preure. Calculate it preure if the volume i changed to 5. 00 L and the temperature to 27C (aume the amount of ga doe not change)
The pressure of the gas would be 0.84 atm when the volume is changed to 5.00 L and the temperature is changed to 27°C.
To calculate the pressure of a gas when the volume and temperature are changed, we can use the ideal gas law equation: PV = nRT, where P is the pressure, V is the volume, n is the number of moles of gas, R is the gas constant, and T is the temperature in Kelvin.
Initial volume (V₁) = 4.20 L
Initial temperature (T₁) = 60°C = 333 K
Initial pressure (P₁) = 1.00 atm
Final volume (V₂) = 5.00 L
Final temperature (T₂) = 27°C = 300 K
To solve for the final pressure (P₂), we can use the equation PV = nRT and compare the initial and final states of the gas.
1: Convert temperatures to Kelvin
Initial temperature (T₁) = 60°C = 333 K
Final temperature (T₂) = 27°C = 300 K
2: Use the equation PV = nRT to compare the initial and final states of the gas.
(P₁)(V₁) = (P₂)(V₂)
3: Rearrange the equation to solve for P₂.
P₂ = (P₁)(V₁) / V₂
4: Substitute the given values into the equation.
P₂ = (1.00 atm)(4.20 L) / 5.00 L
5: Calculate the final pressure (P₂).
P₂ = 0.84 atm
You can learn more about pressure at: brainly.com/question/32099691
#SPJ11
The boiling point of ethanol {CH}_{3} {CH}_{2} {OH} is 78.50^{\circ} {C} at 1 atmosphere. A nonvolatile, nonelectrolyte that dissolves in ethanol is saccharin.
Saccharin is a non-volatile and non-electrolyte substance. It is soluble in ethanol. The boiling point of ethanol is 78.50℃ at 1 atmosphere.
The dissolution of saccharin in ethanol does not affect the boiling point of the solution. The boiling point of ethanol is a physical property that refers to the temperature at which ethanol will change from a liquid to a gas phase. The boiling point of ethanol is 78.50℃ at 1 atmosphere pressure. This is an important factor to consider when using ethanol for various purposes, as it affects its performance and characteristics.
Saccharin, on the other hand, is a non-volatile and non-electrolyte substance. It is a synthetic compound that is widely used as an artificial sweetener in food and beverage products. When saccharin is dissolved in ethanol, it does not affect the boiling point of the solution because saccharin is non-volatile. Therefore, the boiling point of the solution remains at 78.50℃ at 1 atmosphere pressure.
To know more about non-electrolyte visit:
brainly.com/question/14566383
#SPJ11
pls
help me
1.) What is the chemical reaction equation for 1-propanol? 2.) What is the chemical reaction equation for 2-propanol?
The chemical reaction equation for 1-propanol is : CH₃CH₂CH₂OH + 6[O] → 3CO₂ + 4H₂O₂.)
The chemical reaction equation for 2-propanol is : CH₃CHOHCH₃ + 3[O] → 2CO₂ + 3H₂O
1-propanol is also known as n-propanol, 1-propyl alcohol, or propan-1-ol. The chemical formula of 1-propanol is CH₃CH₂CH₂OH. 1-Propanol is used as a solvent, in the manufacturing of various chemicals, and in the production of cosmetics and pharmaceuticals.1-propanol is highly flammable and can react with oxidizing agents, such as potassium permanganate or chromic acid, to produce heat and potentially explosive mixtures.1-propanol is oxidized when it reacts with oxygen, producing carbon dioxide and water. The balanced equation for this reaction is:
CH₃CH₂CH₂OH + 6[O] → 3CO₂ + 4H₂O
The equation for 2-propanol is as follows:
CH₃CHOHCH₃ + 3[O] → 2CO₂ + 3H₂O
The chemical formula of 2-propanol is CH₃CHOHCH₃. 2-propanol is used as a solvent and a cleaning agent. 2-propanol is flammable and should be handled with care when used in an industrial setting.2-propanol is oxidized when it reacts with oxygen, producing carbon dioxide and water. The balanced equation for this reaction is:
CH₃CHOHCH₃ + 3[O] → 2CO₂ + 3H₂O
Learn more about 1-propanol at https://brainly.com/question/30909638
#SPJ11
what is the final concentration of h2so4 when 8.65 ml of 18.1 m h2so4 is diluted to a final volume of 100. ml?
The final concentration of H₂SO₄ after dilution is 1.564 M.
Concentration refers to the amount of a substance present in a given volume or mass of a solution or mixture. It is a measure of how much solute is dissolved or dispersed in a solvent or mixture.
Concentration can be expressed in various ways, such as molarity (moles of solute per liter of solution), mass/volume percent (mass of solute per volume of solution), or parts per million (ppm).
C₁V₁ = C₂V₂
Where:
C₁ = Initial concentration of H₂SO₄
V₁ = Initial volume of H₂SO₄
C₂ = Final concentration of H₂SO₄
V₂ = Final volume of the solution
Given:
C₁ = 18.1 M
V₁ = 8.65 mL
V₂ = 100 mL
C₂ = (C₁ × V₁) / V₂
C₂ = (18.1 M × 8.65 mL) / 100 mL
C₂ = 1.564 M
Learn more about Concentration, here:
https://brainly.com/question/30862855
#SPJ4
Consider a one-dimensional NaCl crystal where each ion has nearest neighbours of the opposite charge a distance ' a ' from it. One of the Na +
ions is displaced by a small amount δ(a>>δ) from its equilibrium position. Obtain an expression for the change in the Madelung constant to the smallest non-vanishing order in δ. What can you conclude from the result.
The change in the Madelung constant is proportional to the displacement, and it is dependent on the charge of the ions, the distance between the displaced ion and its nearby ions, and other factors, according to this conclusion.
Let's investigate the electrostatic potential caused by the displacement of the Na⁺ ion in order to generate an expression for the change in the Madelung constant to the smallest non-vanishing order in.
The total electrostatic potentials contributed by each ion in the crystal lattice are represented by the Madelung constant. The change in the electrostatic potential brought on by the slight movement of one Na⁺ ion will have an impact on how the Madelung constant changes.
We can think about the change in the Madelung constant up to the first-order approximation if the displacement is small (a >> ). Let M stand for the Madelung constant's initial value and M for its variation.
We can analyze the change by taking into account the Madelung constant's contribution from the displaced Na⁺ ion. Since every ion has close neighbors with the opposite charge, the displaced ion's electrostatic potential will be impacted by the nearby ions.
By taking into account the contribution from the nearby ions and applying Coulomb's equation, we may roughly determine the potential at the location of the displaced ion. Let r be the distance between the displaced ion and its nearby ions (a in the equilibrium constant), and let q be the charge of the ions, which is the elementary charge e.
When the displacement is taken into account, the electrostatic potential change can be roughly calculated as V q / (40r), where 0 is the vacuum permittivity.
We can now think about how this hypothetical change affects the Madelung constant. The total electrostatic potential of all the ions affects the Madelung constant. We can write the change as M N V because that is what we are interested in, where N is the total number of ions in the crystal lattice.
When the expression for V is substituted, we get M N (q / (40r)).
The formula for the Madelung constant change to the smallest non-vanishing order in is as follows:
ΔM ≈ N (q / (4πε₀r)) δ.
The change in the Madelung constant is proportional to the displacement, and it is dependent on the charge of the ions, the distance between the displaced ion and its nearby ions, and other factors, according to this conclusion.
To know more about equilibrium constant:
https://brainly.com/question/32542562
#SPJ4
