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A student found that 1.19 g of chromium ($Cr$) formed 1.74 g f chromium oxide. The molar mass of $Cr$ is 52.00 g/mol. What is the empirical formula of chromium oxide?
As with all these problems, we calculate the molar quantities of each substituent, and normalize them according to the masses of the atomic constituents: $"Moles of metal"$ $=$ $(1.19*g)/(52.00*g*mol^-1)=0.0229*mol$ $"Moles...
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Copper will react with sulfur to form a copper sulfide, if 1.500g copper reacts with sulfur to form 1.880g of copper sulfide, what is the empirical formula of the copper sulfide?
The idea here is that you need to use the mass of copper and the mass of the copper sulfide to determine how much sulfur the produced compound contains, then...
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How many grams of sodium sulfide are formed if 1.50 g of hydrogen sulfide is bubbled into a solution containing 2.00 g of sodium hydroxide, assuming that the sodium sulfide is made in 94.0 % yield?
The first step for any chemical reaction is to write out the chemical equation to determine the molar ratios of the reactants and products. Then we will use the molecular...
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A sample of an iron sulfide contains $2.561*g$ of metal, and $2.206*g$ of sulfur. What is the empirical formula of iron sulfide?
$"Moles of iron"$ $=$ $(2.561*g)/(55.85*g*mol^-1)$ $=$ $0.0459*mol$ $"Moles of sulfur"$ $=$ $(2.206*g)/(32.06*g*mol^-1)$ $=$ $0.0688*mol$ If we divide thru by the lower molar quantity, we get, $FeS_(1.5)$. However, by definition, the...
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The element chromium has four naturally occurring isotopes. What is the average atomic mass of chromium, using $""^50Cr=4.34%, ""^52Cr=83.79%, ""^53Cr=9.50%, ""^54Cr=2.37%$?
So let us take the weighted average of your : $(50xx0.0434 + 52xx0.8379+53xx0.095+54xx0.0237)g*mol^-1$ $=$ $??$ The final answer should be close to $52$ $g*mol^-1$ because $""^52Cr$ is the most abundant...
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How many chromium atoms in a $5.67*g$ mass of chromium metal?
The molar mass of elemental chromium is $52.00*g*mol^-1$. What does this mean? It means that if there are $52.00*g$ of chromium metal, there are $"Avogadro's number"$ of chromium atoms, i.e....
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The isotope chromium-51 has a half-life of 28 days. If the original sample had a mass of 28.0 grams, what mass of the chromium-51 sample remains after 84 days?
To find the mass of the chronium-51 sample that remains after $84$ days, we can use the half-life formula. Recall the half-life formula: $color(blue)(|bar(ul(color(white)(a/a)A=A_0(1/2)^(t/h)color(white)(a/a)|)))$ where: $A=$final amount $A_0=$initial amount...
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Sodium chloride is $NaCl$, and sodium sulfide is $Na_2S$. Why are there more sodium ions in the sulfide compound?
Sodium chloride is composed of $Na^+$ ions and $Cl^-$ ions. Now of course salt is neutral; and to ensure this sodium ion and chloride ions combine 1:1. On the other...
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What salts does calcium form with sulfide dianion, and with hydrogen sulfide anion?
$Ca(HS)_2$, $"calcium hydrogen sulfide........."$ Calcium forms a $Ca^(2+)$ ion, and thus requires 2 negative charges to form a neutral salt. The salts of $H_2S$ could be sulfides, $S^(2-)$, or hydrogen...
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Why is $H_2S$ called hydrogen sulfide instead of dihydrogen sulfide?
Both are actually correct. For consistency, IUPAC has defined the "parent molecule" as "sulfane" with acceptable "official" names of both "hydrogen sulfide" and "dihydrogen sulfide" (actually preferred, both are "Compositional...
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