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Fed [463]
3 years ago
5

What is not a guideline required for a valid evidence test?

Chemistry
1 answer:
kirill115 [55]3 years ago
4 0
I just took that quiz , it’s A
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DPLEASE HELP ME TAKE SOO LONG!! (ima fail this test) its a study guide!
8_murik_8 [283]

It’s either b or d, maybe d?

5 0
4 years ago
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Between Lab Period 1 and Lab Period 2, design a separation scheme for all 4 cations. Use the results of your preliminary tests a
fiasKO [112]

Answer:

                    SEPARATION SCHEME FOR  CATIONS

GIVEN  CATIONS : Ag^{+} \ ,  Fe^{3+} , Cu^{2+}, Ni^{2+}

     

    Step 1:   Add 6mol/dm^3 of HCl to the mixture solution

    Result : This would cause a precipitate of AgCl to be formed

    Reaction :  Ag^{+} _{(aq)} + Cl^{-} _{(aq)}  ---------> AgCl(ppt)

    Step 2 : Next is to remove the precipitate and add H_2S to the remaining          

                 solution in the presence of 0.2 \ mol/dm^3 of HCl

     Result : This would cause a precipitate of CuS to be formed

     Reaction :  Cu^{2+}_{(aq)} + S^{2-}_{(aq)} ------> Cu_2S(ppt)

 

     Step 3: Next remove the precipitate then add 6 \ mol/dm^3 of aqueous      

                 NH_3 (NH_3 \cdot H_2 O) , process the solution in a centrifuge,when the  

                 process  is done then sort out the  precipitate from the  solution

                 Now this precipitate is   Fe(OH)_3 and the remaining solution

                contains  (Ni (NH_3)_6)

                 Next take out the precipitate to a different beaker and add HCl

                to it   this will dissolve it, then add a drop of NH_4SCN this will

                form  a precipitate  Fe(SCN)_{6}^{3-} which will have the color of

                 blood  indicating the presence of Fe^{3+}

             

   Reaction :   F^{3+}_{(aq)} + 30H^-_{(aq)} --------->Fe(OH)_3_{(aq)}

                        Fe (OH)_{(s)} _3  + 3H^{+}_{aq} -------> Fe^{3+}_{aq} + 3H_2O_{(l)}

                         Fe^{3+} + 6SCN^{-} -----> Fe(SCN)_6 ^{3-}

                      Now the remaining mixture contains Ni^{2+}

     

       

Explanation:

6 0
3 years ago
Work=? time=5s Power = 40w
antiseptic1488 [7]

Answer:

200 J

Explanation:

Work = Power x time

Work = (40w)(5s)

Work = 200 J

5 0
3 years ago
C12H7Cl3FNaO2 what are the elements in that chemical formula
Bess [88]

Answer:

hope it helped you

Explanation:

Sodium fluoride - 5-chloro-2-(2,4-dichlorophenoxy)phenol (1:1:1) | C12H7Cl3FNaO2 |

3 0
3 years ago
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