Xiao Wang's mother bought a big and beautiful "gold" decorative pendant in Chongqing department store on May Day. Xiao Wang and his parents in the second day of junior high school really want it.

Scheme 1: (1) Put the balance on a horizontal platform, move the zero scale at the left end of the balance, and adjust the balance nut to balance the beam of the balance.

(2) Pendant weight:100g+50g+10g+5g+2.2 =167.2g;

Pendant volume: v = v2-v1= 40ml-30ml =10ml =10cm3;

Pendant density: ρ = mv =167.2g10cm3 =16.72g/cm3;

Scheme 2: (4) Lift the pendant out of the water, then pour water into the glass, so that the water surface is still at B, and measure the total mass of the glass and water at this time to be 97g. So the volume of the pendant: V=97g? 86g 1g/cm3 = 1 1 cm3。

(5) Calculate the density of the pendant with the density formula: ρ = mv =167.2g1cm3 =15.2g/cm3 =15.2x103kg/m3.

(6) In this experiment, the equivalent substitution method is used to measure the volume of the pendant.

There are two reasons for the large error in the experiment operation of scheme 2: first, some water was taken away when the pendant was taken out; Second, when round glass is used, its own error is large.

So the answer is: Scheme 1: (1) balance nut; (2) 167.2; 10; 16.72; Option 2: (4) Location B; 1 1; (5) 15.2× 103; (6)B； The pendant took away some water when it was taken out; When round glass is used, its own error is large.