<u>Answer:</u>
17%
<u>Explanation:</u>
Mass of a piece of copper calculated by student = 8.3 grams
Actual mass of copper = 10 grams
We know the formula for the percent error:
Percentage error = (| experimental value - actual value | / actual value) * 100
So substituting the given values in the above formula:
Percent error = (|8.3 - 10| / 10) * 100 = (1.7/10) * 100 = 17%
Answer:
is the density of solid calcium.
Explanation:
Formula used :

where,
= density
Z = number of atom in unit cell
M = atomic mass
= Avogadro's number
a = edge length of unit cell
We have:
r = 197 pm = 



M = 40 g/mol
Z = 4
On substituting all the given values , we will get the value of 'a'.


is the density of solid calcium.
Answer: But because part 2 stays the same
2Pb(NO₃)₂ = 2PbO + 4NO₂ + O₂
m{Pb(NO₃)₂}=9.9 g
m'{PbO}=5.5 g
M{Pb(NO₃)₂}=331.2 g/mol
M{PbO}=223.2 g/mol
w-?
w=m'{PbO}/m{PbO}
m{PbO}=M{PbO}m{Pb(NO₃)₂}/M{Pb(NO₃)₂}
w=m'{PbO}M{Pb(NO₃)₂}/[M{PbO}m{Pb(NO₃)₂}]
w=5.5*331.2/[223.2*9.9]=0.8244 (82.44%)
Gabbro is usually made up of such as pyroxene, plagioclase, amphibole and olivine which makes it an intrusive igneous rock. It is not considered as a mineral since it is composed of an aggregate of minerals or non-minerals and does not have one specific chemical composition.