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>
The synthesis of a compound from its elements in their standard state, accompanied by a change in energy that is known as standard enthalpy of formation of a compound. The standard state of a substance is the most stable physical state of the compound that exist at STP that is at 1 atm, 273 K temperature. So the answer is yes, the energy change accompanying the synthesis of a compound from its elements in their standard state.
Answer:
A
Explanation:
has properties that are different from the original substances.
Answer:
A. NaOH.
Explanation:
The pH of the solution = 6.8.
- The pH of the solution increases as the basicity of the solution increases.
- The basicity of the solution will increase by adding bases that have the ability to produce OH⁻.
So, NaOH and NH₃ "bases" will increase the pH of the solution.
while, HCl and HNO₃ "acids" will increase the acidity of the solution, thus pH will decrease.
But, NaOH will increase the pH of the solution the most because it is dissociates completely to OH⁻ , while NH₃ is weakly ionized "does not dissociate completely".
<em>So, NaOH will increase the pH the most when added to the solution.</em>
Your answer should be, B) one liter of water equals one gram of water
