A) 13g
b) 2.68g (2dp)
c) 51.87g
Tip: mass = moles x Mr
What is the net ionic equation
2 H^+ + SO4^2- + Ca^2+ + 2 i^- = CaSo4 + 2H^+ +2i ^-
cancel the spectator ion that is the ions which does not take place nin the reaction
for this case is 2 H^+ and 2 i^-
the net ionic equation is therefore
=Ca^2+ + SO4^2- = CaSO4
The composite material is composed of carbon fiber and epoxy resins. Now, density is an intensive unit. So, to approach this problem, let's assume there is 1 gram of composite material. Thus, mass carbon + mass epoxy = 1 g.
Volume of composite material = 1 g / 1.615 g/cm³ = 0.619 cm³
Volume of carbon fibers = x g / 1.74 g/cm³
Volume of epoxy resin = (1 - x) g / 1.21 g/cm³
a.) V of composite = V of carbon fibers + V of epoxy resin
0.619 = x/1.74 + (1-x)/1.21
Solve for x,
x = 0.824 g carbon fibers
1-x = 0.176 g epoxy resins
Vol % of carbon fibers = [(0.824/1.74) ÷ 0.619]*100 =<em> 76.5%</em>
b.) Weight % of epoxy = 0.176 g epoxy/1 g composite * 100 = <em>17.6%</em>
Weight % of carbon fibers = 0.824 g carbon/1 g composite * 100 = <em>82.4%</em>
