2.05 × 108 kg of water is pumped up through a vertical height of 500 m.

1 x 10¹²J

Explanation:

Given parameters:

Mass of the water pumped  = 2.05 x 10⁸kg

Height  = 500m

Unknown:

Potential energy = ?

Solution:

The potential energy amassed by water at this height is expressed as;

           P.E  = mgH

m is the mass

g is the acceleration due to gravity

H is the height

        Insert the parameters and solve;

     P.E  = 2.05 x 10⁸ x 9.8 x 500 = 1 x 10¹²J

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz