This is a redox reaction, meaning reduction-oxidation reaction. This represents the reaction in one side of the electrode in an electrolysis set-up. First, we find the oxidation number of Cu in CuSO4:
(ox. # of Cu)+ ox.# of S + 4(ox.# of oxygen) = 0
(ox. # of Cu) + (6) + 4(-2) = 0
ox. # of Cu = 2+
CuSO4 ---> Cu + SO42-
Cu2+ + SO42- ----> Cu + SO42-
Cu2+ -----> Cu + 2e- (net ionic reaction)
The stoichiometric equation would be 2 electrons per mole Copper. Copper has a molar mass of <span>63.5 g/mol. Then, it would only need 2 electrons.
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Answer:
D.) The nuclear model describes the atom as a dense, positive nucleus surrounded by a cloud of negative electrons.
Answer:
Number of molecules = 23.9 × 10²³ molecules
Number of moles = 3.97 mol
Explanation:
Mass of HNO₃ = 250 g
Number of moles = ?
Number of molecules = ?
Solution:
Number of moles = mass / molar mass
Number of moles = 250 g/63 g/mol
Number of moles = 3.97 mol
Number of molecules:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 250 g of HNO₃:
250 g/ 63 g/mol = 3.97 mole
3.97 × 6.022 × 10²³ molecules = 23.9 × 10²³ molecules
Answer:
group # = # valence electrons
group 2= 2 valence electrons
Explanation:
Mg is in group #2 and subsequently has 2 valence electrons (electrons on the outermost shell)
Answer:
A. 2
Explanation:
A particle of water is made up of two hydrogen atoms and one oxygen atom. However, the question asked for how many types of atoms there are, so the answer is 2.
