Speed is calculated by multiplying the time of travel by the distance traveled.

Actually, No.  That operation doesn't give you the speed, and that statement is false.  

One clue is the units.  If you multiply time by distance, you'd get an answer with units of hour-miles or second-meters.  These are absurd units, with no physical significance.

Speed = (distance covered) DIVIDED BY (time to cover the distance)

When you divide distance by time, you get an answer with units like "miles per hour" or "meters per second".  Without going into a long-winded discussion, I can't PROVE to you that this is actually the correct speed, but  these units sure do smell a lot better.

  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