Question

DATA Mars 250ml, beaker /32 059 Mass 250ml. beaker & alloy 133.026g Mass copper wire (before reaction) / 958. Mass copper wire (after reaction) Mass 250ml. beaker & silver Mass 400ml. beaker 1.7539 132 664 149.939 150. 2779 Maxx 400ml, beaker & copper oxide

I need questions :
Percent silver in alloy?
Mass of copper in copper oxide?
Mass of copper in alloy?
Percent copper in alloy?

Please show work!

Answer 1

Mass of Alloy = (Mass 250 mL beaker & alloy) - (Mass 250 mL beaker) = 133.026 g - 132.059 g = 0.967 g

Mass of silver = (Mass 250 mL beaker & silver) - (Mass 250 mL beaker) = 132.664 g - 132.059 g = 0.605 g

Percent silver in alloy = (Mass of silver/Mass of alloy) x 100

= (0.605 g/0.967 g)x100

= 62.56%

Mass of copper wire reacted = (Mass of copper wire berofe reaction)-(Mass of copper wire after reaction)

= 1.958g - 1.753 g

= 0.205 g

Mass of copper oxide = (Mass 400 mL beaker & copper oxide) - (Mass 400 mL beaker)

= 150.277 g - 149.939 g

= 0.338 g

Mass of copper in copper oxide can be caluclated as

mass of copper oxide (CuO) = 0.338 g

# of mol of copper oxide (CuO) = # mol of copper = (0.338 g/79.55 g/mol) = 0.004249 mol

Mass of copper in copper oxide = (0.004249 mol)(63.55g/mol) = 0.2700 g

Mass of copper in Alloy = Mass of copper wire reacted = 0.205 g

Percent copper in Alloy = (Mass of copper/Mass of alloy) x 100

= (0.205 g/0.967 g)x100

= 21.20%