<span>Answer:
A 1.00 L solution containing 3.00x10^-4 M Cu(NO3)2 and 2.40x10^-3 M ethylenediamine (en).
contains
0.000300 moles of Cu(NO3)2 and 0.00240 moles of ethylenediamine
by the formula Cu(en)2^2+
0.000300 moles of Cu(NO3)2 reacts with twice as many moles of en = 0.000600 mol of en
so, 0.00240 moles of ethylenediamine - 0.000600 mol of en reacted = 0.00180 mol en remains
by the formula Cu(en)2^2+
0.000300 moles of Cu(NO3)2 reacts to form an equal 0.000300 moles of Cu(en)2^2+
Kf for Cu(en)2^2+ is 1x10^20.
so
1 Cu+2 & 2 en --> Cu(en)2^2+
Kf = [Cu(en)2^2+] / [Cu+2] [en]^2
1x10^20. = [0.000300] / [Cu+2] [0.00180 ]^2
[Cu+2] = [0.000300] / (1x10^20) (3.24 e-6)
Cu+2 = 9.26 e-19 Molar
since your Kf has only 1 sig fig, you might be expected to round that off to 9 X 10^-19 Molar Cu+2</span>
X will be in group 5, since if you exchange the valencies of Na with any element on group 5, you will get Na3X
Answer is: mass of the mixture is 24,47 g.
1) N(Na₂SO₄) = 3,5·10²².
n(Na₂SO₄) = 3,5·10²² ÷ 6·10²³ 1/mol.
n(Na₂SO₄) = 0,058 mol.
m(Na₂SO₄) = 0,058 mol · 142 g/mol.
m(Na₂SO₄) = 8,24 g.
2) n(H₂O) = 0,500 mol.
m(H₂O) = 0,5 mol · 18 g/mol.
m(H₂O) = 9 g.
3) m(total) = 8,24 g + 9 g + 7,23 g.
m(total) = 24,47 g.
n - amount of substance.
The first ionization energy of a known element is the energy
it needs to remove its highest energy or outermost electron. It is done to make
a neutral atom be a positively charged ion. The first ionization energy of neon
as a chemical equation is this:
Ne (g) -> Ne+ (g) + e-
Answer:
Chemical change
Explanation:
From all indicators, Aurelia is seeing a chemical change occurring in the reaction here.
A chemical change is a change in which new substances are produced. For every chemical change:
- they are not easily reversible
- they lead to production of new kinds of substances
- involves mass change
- require considerable amount of energy.
We start off and end with:
Metal + Acid → Black metal + rising gaseous bubbles
Clearly, it is shown that new products are formed and this reaction is impossible to reverse in order to get the reactants back.
This is a typical chemical change.
