Answer:
+5
Explanation:
it hs 5 more protons thant electrons, so it has a positive charge of 5
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>
N(H₂O):n(NO)=6:4(3:2), n(NO)=2·3,5mol÷3=2,33mol
So it is a).
Answer:
22.8 L
Step-by-step explanation:
We can use <em>Gay-Lussac's Law of Combining Volumes</em> to solve this problem:
Gases <em>at the same temperature and pressure</em> react in simple whole-number ratios.
1. Write the chemical equation.
Ratio: 2 L 1 L
Ca(s) + 2HCl(g) ⟶ CaCl₂(s) + H₂(g)
V/L: 11.4
2. Calculate the volume of HCl.
According to the law, 2 L of HCl form 1 L of H₂.
Then, the conversion factor is (2 L HCl/1 L H₂).
Volume of HCl = 11.4 L H₂ × (2 L HCl/1 L H₂)
= 22.8 L HCl
The number of moles of NaOh that are contained in 65ml of 2.20M solution NaOh in H2o is calculated using the below formula
moles = molarity x volume /1000
that is 65 x2.20 /1000= 0.143 moles