Physical and chemical laws describing the properties and behavior of gases.

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How much Carbon Dioxide would be required to displace enough oxygen to prevent ignition?

In air, how much $CO_{2}$ would be required to prevent a match to light or a butane lighter to work? I have a basement office that is unusable because of an apparent lack of Oxygen, currently it is ...
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10 views

Plotting a calibration curve for Gas-Liquid Chromatography

Textbook solution: Why aren't the points like this: (20,5) (40,10) (60,15) (a,7) then to plot the curve we use y=mx+c and then find the value of 'a'
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49 views

Convert co2 ppm volume to ppm weight?

I'm using a sensor that measures CO2 in ppm by volume aka atmosphere. What I'm using it for is to measure CO2 concentration in water which is measured in ppm by weight. This is what I have so far ...
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510 views

What is the carbon dioxide content of a soda can or bottle?

I sort of know how carbonated beverages are carbonated: a lot of $\ce{CO2}$ gets pushed into the liquid, and the container is sealed. There are at least two things I don't know. First, how much carbon ...
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46 views

How do I calculate the temperature of hot air in Kelvin?

The question simply says "calculate the temperature of hot air in Kelvin" on a data calculation section for this lab. We recorded: volume change on cooling = 170 mL original volume of hot air = 20 ...
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139 views

Boyle's Law of pressure and volume

Boyle's Law states that: Pressure is inversely propotional to Volume. But if we take an example of a balloon. As we fill air in it it's pressure increases but it's volume also increases. Can anyone ...
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40 views

How to do Gas Laws [closed]

A sample of gas in a balloon has an initial temperature of 5 °C and a volume of 1010L . If the temperature changes to 59 °C, and there is no change of pressure or amount of gas, what is the new ...
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54 views

How does the number of moles of gas affect the rate of effusion?

According to Graham's Law, the effusion rate of a gas is inversely proportional to the square root of the molar mass of the gas. However, consider this situation: We have 1 balloon with 1 mole of ...
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27 views

Evaporation velocity of ethanol: adding ethanol vapour to a gas mixture

I need to add a known amount of ethanol vapour to a gas mixture (He/Ar). To do that I let the mixture bubble in liquid ethanol kept at a known temperature (14 C). The system is made of a large steel ...
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73 views

What does negative pressure mean in the context of this manometer?

I have a basic question on a closed manometer: I see that in this case the pressure of gas is lower than that of the liquid, which is why the liquid is higher on the left side. Now, what I don't ...
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1answer
71 views

The air we breathe

The air we breathe is a mixture of nitrogen ($\ce{N2}$, 80%), oxygen ($\ce{O2}$, 20% inhaled, 16% exhaled) and carbon dioxide ($\ce{CO2}$, 0% inhaled, 4% exhaled) all of which may be assumed to ...
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32 views

Calculation of molar volume at certain temperatures and pressures

I was wondering are there any calculators/calculations/means of calculation of molar volume at certain temperatures and pressures that don't use the Ideal Gas Law? i.e. The calculation of molar ...
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73 views

Is it possible to use diatomic carbon to utilize a new type of fuel that takes away the waste product of carbon dioxide being released into the air? [closed]

These days, we as a community what to polish and make our world a greener environment. I found a way to accomplish this task, however I don't know if it is applicable. I am wondering if the use of ...
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1answer
62 views

Ideal Gas Problem

When I work through the following problem it is unclear to me why 0.00120 mmHg is converted to 0.00332 mmHg. "What is the temperature of 0.00332 g of Hg in the gas phase with pressure of 0.00120 ...
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136 views

Is there a hydrophobic gas?

I am looking into the subject of water repelling and have been led to the hydrophobic subject area. I have two questions regarding this subject. Is there a hydrophobic gas ? If a hydrophobic ...
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68 views

Thermodynamics Problems!

A cylinder, 0.5m long and of cross section S, closed at each end is fitted with a smooth thermally insulating piston, so as to contain gas in each end A and B. Initially, the piston is in equilibrium ...
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53 views

Ideal gas derivations

For an ideal gas, how can someone obtain this: $$ \bar{V}dP = RdT- P \bar{dV}$$ from which it can de deducted, that for a constant temperature $$ \frac{dP}{\bar{dV}} = -RT $$
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Doubt regarding dimensions in van der Waal's real gas formula

In the van der Waal's formula for real gases $\left( p+\frac{a}{V^2}\right)(V-b)=nRT$, what are the dimensions of $a$ and $b$? I learnt that $a$ is related to the average force of attraction between ...
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55 views

Doubt regarding units in the ideal gas formula

I have learnt the ideal gas equation $PV=nRT$. However, I have some doubts regarding the units of the quantities in this equation. When we take the gas constant $R=8.314Jmol^{-1}K^{-1}$, what should ...
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1answer
68 views

Ideal Gas Law, P,T,V Change => adiabatic?

Given the expansion of an ideal gas, Pressure $P$, Volume $V$ and Temperature $T$ change from $P_1$, $V_1$, $T_1$, to $P_2$, $V_2$, $T_2$. a) Does the standard ideal gas law predict correct end ...
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31 views

Gas law with molecules at the same time

How many grams of oxygen are present at 25.0 C in a 5.00L tank of oxygen enriched air? The total pressure is 30.0 atm and the only other gas is nitrogen with a pressure of 17.0 atm. After converting ...
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47 views

Gas law and moles

A sample of solid magnesium reacts with excess HCl solution to form hydrogen gas The sample of gas measures 1.628 L at 22.0C and 0.930 atm pressure. a) how many moles of gas were collected? b) how ...
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61 views

Gas Law problems with stoichiometry

Consider the following reaction : $\ce{H2 + Cl2 -> 2HCl}$ A) If you have 15.00 liters of hydrogen reacting with 10.00 liters of chlorine at STP, how many liters of HCl would you produce? B) What ...
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150 views

A gas law problem to find the molar mass

A gaseous sample of a compound has a density of 0.977 g/L at 710.0 torr and 100.00C. What is the molar mass of this compound? When I worked the problem I got 29.9 g/mol is that right?
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291 views

Volume of gas needed to heat air in room

How much methane gas ($\text{cm}^3$) is required heat $150\text m^3$ of air by 10℃? Please help! I thought this wouldn't be too difficult but I've been stuck for at least an hour now- so frustrating! ...
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2k views

Isothermal vs. adiabatic compression of gas in terms of required energy

I am working on an instruction manual of sorts to be used with an introductory course in thermodynamics. As an example of problem solving, I attempt to answer the following question: If you have ...
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29 views

Specific gas constant for two gases

I have a mixture with 1 part of gas A, and 7 parts gas B. This ratio is in terms of mass. Gas Molar Mass (kg/mol) A 0.17034 B 0.034 I'm trying to find ...
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1k views

How to determine whether a compound is gas or liquid or solid?

My book says, methyl chloride, methyl bromide, ethyl chloride and some cholorofluromethanes are gases at room temperature, whereas higher members are liquids or solids. Why? With this question, I ...
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135 views

How to determine CO2 concentration from %oxygen and ppm CO

I have an excel file where it computed according to: $ \%\ce{CO2} = 20.9 - \%\ce{O2} - ppm \ce{CO}/(2*10000) $ I really can't figure out if this is correct or not? Why subtract from 20.9 and where ...
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1answer
224 views

Calculate vapor pressure from volume

For a chemistry lab, I'm required to calculate the vapor pressure of some organic solvents... methanol, ethanol, and propanol, in addition to an "unknown" sample of some solvent. In the lab, we were ...
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190 views

Sodium Hypochlorite Production Explanation

One reaction used to form sodium hypochlorite (A type of bleach) is as follows: $\ce{2NaOH(aq) +Cl2(g)->NaOCl(aq) + NaCl(aq) + H2O(l)}$ Provided the sodium hydroxide is dissolved in some ...
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Why is the carbon dioxide we exhale transparent?

Why is carbon dioxide that comes from dry ice opaque and smoky while the carbon dioxide that we exhale transparent?
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Is this relation in case of a mixture of ideal gases valid?

I came across the following relation in a book(written as a fact, with no proof), for a mixture of ideal gases both at the same pressure and temperature. The final volume of the mixture of gases ...
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1answer
197 views

Forms of Henry's law versus ideal gas law

This might be a slightly daft question as I'm a physicist rather than a chemist, but I have a slight problem in using Henry's law which I think I can circumvent using the ideal gas law – I'd be ...
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106 views

Gas law proportion question

The volume of a mole of gas is: ...
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162 views

Finding Pv in Pv=nRT for molecular hydrogen

I'm attempting to write a small program that will calculate the values for the Ideal Gas Law, specifically for molecular Hydrogen (H2) in space. Eventually, this will grow to be a sort of ...
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106 views

Ratio of concentrations

I'm studying for my chemistry final and having a hard time with this question on one of the practice exams. Here's the question: At $20$ degreees Celsius, Henry's Law constant for Ar is half of that ...
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327 views

Gas Electrode Working

How does a SHE electrode work? Does the $H_2$ gas get absorbed on the platinum electrode? How is it reduced? How are electrons transferred from the adsorbed gas to the solution? How is $H^+$ ...
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1answer
21 views

What is the difference between a chemical state and just a combination?

I don't think a combination also can be called a "state" i.e. that the chemical state of vapour or solid would be just a combination. When I read Wikipedia about "chemical state" it refers to just a ...
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1answer
79 views

Why does the conversion of SO₂ to SO₃ require high pressure?

The conversion of sulphur dioxide to sulphur trioxide in the contact process for the manufacture of sulphuric acid requires the following condition: Temperature: 450 degrees Pressure: 1-2 atm, ...
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146 views

How to derive partial gas equation?

I was given a question as follows: If the following gasses are to mix, what is the partial pressure of the Ne gas? The correct answer is 0.1. I cannot figure out how my professor derived ...
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187 views

Why does gas particle velocity affect rate of effusion?

I understand why smaller particles have more velocity, but I don't understand what velocity has to do with rate of effusion: My reasoning is thus: Pressure is the number of impacts of particles in ...
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1k views

If gases turn into liquids under pressure, what does carbon dioxide turn into?

Since there is no liquid state of carbon dioxide, what will carbon dioxide turn into when exposed to high pressure?
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229 views

Dalton's Law Of Partial Pressures

I'm given a container of volume of 4.0 Litres that containes Nitrogen at $25 ^\circ C $ and 803 kPa. This container is connected by a valve to another container of 10.0 litres volume that containes ...
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260 views

Understanding dissolution of CO₂ in Selexol and Rectisol

I'm trying to understand pre-combusiton carbon capture processes as described in this presentation. I'm told that solvents such as chilled methanol ($\small\ce{CH4O}$) and dimethyl ethers of ...
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455 views

What is a rigorous definition of gas volume, and how is the Van der Waals equation derived?

I am confused about the justification for the corrections to the ideal gas law in the Van der Waals equation: $$p=\frac{nRT}{V-nb}-a(\frac{n}{V})^2$$ I understand that the equation attempts to ...
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Why are equations of state for a non-ideal gas so elusive?

The ideal gas equation (daresay "law") is a fascinating combination of the work of dozens of scientists over a long period of time. I encountered Van der Waal's interpretation for non-ideal gases ...