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A, let the quality of the generated precipitate be x, then:

CuCl2+2NaOH═Cu(OH)2↓+2NaCl？

80? 98

40gx20%=8g x？

808 g = 98 times

Solution: x=9.8g?

Therefore, A is correct.

B, let the mass fraction of hydrochloric acid be y, then:

NaOH+HCl═NaCl+H2O？

40? 36.5

20gx20%？ 40g？ y

=4g

404g=36.540g？ y

Solution: y = 9. 1.25%

So, B is wrong.

C, adding sodium hydroxide solution will not produce precipitation at the beginning, but only after the final consumption of hydrochloric acid; So, c is wrong;

D. From the two chemical reactions and graphs in the above analysis, it can be seen that when 60g sodium hydroxide solution is added, copper chloride and hydrochloric acid are just consumed, so the solute in the final solution is only sodium chloride, that is, sodium chloride solution, so D is correct.

So choose ad.