yup it's correct because we multiply cm by cm twice
Dissolving is your answer to this question. Becuase when something dissolves it is no longer in the same shape or state cause if something dissovles then goes away into another state.
Answer:
a) +640 kJ/mol or +1.06x10⁻¹⁸ J
b) +276 kJ/mol
Explanation:
To dissociate the molecule, the bond must be broken, thus, it's necessary energy equal to the energy of the bond, which can be calculated by:
E = (Q1*Q2)/(4*π*ε*r)
Where Q is the charge of the ions, ε is a constant (8.854x10⁻¹²C²J ⁻¹ m⁻¹), and r is the bond length. Each one of the ions has a charge equal to 1. The elementary charge is 1.602x10⁻¹⁹C, which will be the charge of them.
1 mol has 6.022x10²³ molecules (Avogadros' number), so the energy of 1 mol is the energy of 1 molecule multiplied by it:
E = 6.022x10²³ *(1.602x10⁻¹⁹)²/(4π*8.854x10⁻¹²*2.17x10⁻¹⁰)
E = +640113 J/mol
E = +640 kJ/mol
Or at 1 molecule: E =640/6.022x10²³ = +1.06x10⁻²¹ kJ = +1.06x10⁻¹⁸ J
b) The energy variation to dissociate the molecule at its neutral atoms is the energy of dissociation less the difference of the ionization energy of K and the electron affinity of F (EA):
498 = 640 - (418 - EA)
640 -418 + EA = 498
222 + EA = 498
EA = +276 kJ/mol
Answer:
<h2>
Kevlar has unique properties such as:</h2><h2><em>
High tensile strength</em>
, <em>
high toughness</em>
, and <em>
chemical stability </em>
at high temperatures<em>
</em>
in polyamides (polymer with repeating unit links by amide bonds.) </h2><h3>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</h3>
Δ What is Kelvar? Δ
~ Kevlar is a heat-resistant and strong synthetic fiber
~ Kevlar is widely used as a friction material in the automotive industry, and a combustion protection material in the aerospace industry. <em>~Looked that up!</em>
<h3>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</h3>
<em>Hope I helped!!!</em>
<em>GL :)</em>
Descriptive investigations are mainly questions to uncover information. it does not have an hypothesis. It is mainly gathering information, it is not repeatable as you are just asking questions
