The weighted average is the sum of each individual nuclide, multiplied by its isotopic abundance. So, we simply do the arithmetic: $0.7577xx34.969+0.2423xx36.966 = ???$ amu Then look at to...
1 Answers 1 viewsOkay, so you've performed the classic magnesium oxide lab. I assume that you have your data, so I'll just walk you through this from a theoretical standpoint. So, you...
1 Answers 1 viewsIt is abundantly clear that magnesium is in vast molar excess: i.e. $"Moles of metal"$ $=$ $(100*g)/(24.31*g*mol^-1)$ $~=$ $5*mol$ $"Moles of dioxygen"$ $=$ $(2.5*g)/(32.00*g*mol^-1)$ $~=$ $0.08*mol$ Clearly, $O_2$ is the...
1 Answers 1 viewsThe law of conservation of matter requires that the mass of the reactants is the same as the mass of the products in a chemical reaction. The compound being composed...
1 Answers 1 viewsThe idea here is that you need to use the amount of hydrogen and the amount of carbon found in the $"5.0-g"$ sample of this unknown compound to determine the...
1 Answers 1 viewsTo find the percentage of the metal, first determine the difference between the mass of the compound and the mass of chlorine. This will give the mass of the metal....
1 Answers 1 views$MgCO_3(s)+DeltararrMgO(s) + CO_2(g)$ And we would have to heat the magnesium salt VERY fiercely to get complete decarboxylation. $"Moles of carbon dioxide LOST"$ $=$ $(4.40*g)/(44.01*g*mol^-1)$ $=0.010*mol$ And therefore in...
1 Answers 1 viewsThe 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...
1 Answers 1 viewsThe 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" +...
1 Answers 1 viewsThionyl chloride reacts quantitatively (and violently) with water as represented by the following reaction: $SOCl_2(l) + 2H_2O(l) rarr SO_2(g)uarr + 2HCl(aq)+Delta$ $"Moles of thionyl chloride"=(35.0*g)/(118.97*g*mol^-1)=0.294*mol.$ And CLEARLY, thionyl chloride is...
1 Answers 1 views