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In a chemical reaction, exactly 2 mol of substance A react to produce exactly 3 mol of substance B. How many molecules of substance Bare produced when 28.3 g of substance A reacts? The molar mass of substance A is 26.5 g/mol.
The only two substances that are of interest to you are $"A"$ and $"B"$, so you can write the chemical equation as $color(red)(2)"A" + ... -> color(blue)(3)"B" +...
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Molar mass of substance A in material Eu(A)3 is 238g/mol. 0.476g of substance A was burned and produced 1.408g of CO2 and 0.252g of H2O. Substance A is made up of carbon, hydrogen and oxygen. What is the chemical formula for substance A?
The way I see it, the part about how The molar mass of substance $"A"$ in material $"Eu"("A")_3$ is $"238 g mol"^(-1)$ does not make...
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How would you determine the molecular formula of a substance that contains 92.3%C and 7.7%H by mass. This same substance when in the gas phase has a density of 0.00454g/ml at stp conditions?
Your strategy here will be to use a sample of this compound to help you determine its empirical formula use the equation, the gas' , and the known STP...
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A carbon compound contains 12.8% of carbon, 2.1% of hydrogen and 85.1% of bromine. The molecular weight of the compound is 187.9. What is the molecular formula of the compound?
(Atomic weight: H = 1.008, C = 12.0, Br = 79.9)
As always with these problems, it is useful to assume $100*g$ of unknown compound....and thus find an empirical formula... $"Moles of carbon"=(12.8*g)/(12.011*g*mol^-1)=1.066*mol.$ $"Moles of hydrogen"=(2.1*g)/(1.00794*g*mol^-1)=2.084*mol.$ $"Moles of bromine"=(85.1*g)/(79.90*g*mol^-1)=1.066*mol.$ And we...
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Hydrogen peroxide has the empirical formula HO and an empirical formula weight of 17.0 amu. If the molecular weight is 34.0 amu, what is the molecular formula?
First, you want to find the ratio between the empirical formula and molecular formula; that is, how much has the molecular formula been simplified to reach the empirical formula. We...
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Michael has a substance that he puts in container 1. The substance has a volume of 5 cubic meters. He then puts it in container 2 and it now has a volume of 10 cubic meters. In which phases(s) is the substance?
$1*m^3-=1000*L$, and this is a very large volume. If you ever shift $4-5*m^3$ of concrete this is a good few hours hard work. Now gases have the property that they...
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A chemist dissolved crystals of an unknown substance into water at room temperature. He found that 33 g of the substance can be dissolved into 100 mL of water. What property of the unknown substance was the chemist most likely investigating?
The solubility of a substance is a measure of how much can dissolve in a certain at a given temperature, and is usually expressed in units of grams of solute...
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How do we differentiate between a $"molecular element"$, and a $"molecular compound"$? And how are these differentiated from $"non-molecular"$ species?
The distinction between a molecular and non-molecular structure is one of the most important criteria with which to assess . But here, if we have an elemental molecule, we have...
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What is the relationship between molecular weight and rate of diffusion?
The rate of diffusion ($U_(rms)$) is given by: $U_(rms)=sqrt((3RT)/(MM))$ Where MM is the molar mass of the gas. Thus, when $MM$ increases, the diffusion rate will decrease.
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A sample of a pure substance with a mass of 0.963g contains 4.84x1-^-3 moles. What is the formula weight of the substance comprising the sample?
We're asked to calculate the formula weight of a pure substance, knowing that $4.81xx10^-3$ $"mol"$ has a mass of $0.963$ $"g"$. To calculate the formula weight (relative , atomic weight,...
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