How many grams of chromium are needed to react with an excess of CuSo4 tp produce 27 g Cu?
14.7
Solution:
The chemical equation for this reaction is: 3CuSO4 + 2Cr = Cr2(SO4)3 + 3Cu
The amount of Cu produced in reaction is n(mol) = m(g) / MW(g/mol)
n(Cu) = 27 / 63.5 = 0.425 mol
According to the chemical equation n(Cr) = 2⁄3 ∙ n(Cu)
n(Cr) = 2⁄3 ∙ 0.425 = 0.283 mol
The mass of Cr is
m(g) = n(mol) ∙ MW(g/mol)
The molar weight of Cr is equal to its atomic weight in the periodic table of elements (MW(Cr) = 52 g/mol)
m(Cr) = 0.283 ∙ 52 = 14.7 g Answer: m(Cr) = 14.7 g
Just so the chem teachers know what your school subject is...
help w this pls
To determine the number of grams of chromium needed to react with an excess of CuSO4, we first need to understand the stoichiometry of the reaction. The balanced equation for the reaction between chromium and CuSO4 is:
Cr + CuSO4 -> Cu + Cr2(SO4)3
From the balanced equation, we can see that one mole of chromium (Cr) reacts with one mole of copper sulfate (CuSO4) to produce one mole of copper (Cu).
1. Calculate the molar mass of Cu:
The molar mass of Cu is 63.55 g/mol.
2. Convert the given mass of Cu to moles:
Given mass of Cu = 27 g Cu
Number of moles of Cu = (Given mass of Cu) / (Molar mass of Cu)
Number of moles of Cu = 27 g / 63.55 g/mol
3. Determine the moles of Cr required:
From the balanced equation, the mole ratio between Cr and Cu is 1:1. Therefore, the number of moles of Cr required is equal to the number of moles of Cu.
Number of moles of Cr = Number of moles of Cu = 27 g / 63.55 g/mol
4. Calculate the mass of Cr required:
Mass of Cr required = (Number of moles of Cr) x (Molar mass of Cr)
Mass of Cr required = (27 g / 63.55 g/mol) x (molar mass of Cr)
To find the molar mass of chromium, we need to know which compound of chromium is being used in the reaction. Please specify the compound of chromium, and I can provide you with the molar mass and complete the calculation.
1. Write the equation and balance it.
2. Convert 27 g Cu to moles. moles = grams/molar mass.
3. Using the coefficients in the balanced equation, convert moles Cu to moles Cr.
4. Now convert moles Cr to grams. g = moles x molar mass.