Answer:
V₂ = 946.72 mL
Explanation:
Given data;
Initial pressure = 0.926 atm
Initial volume = 457 mL
Temperature = constant = 29.5°C
Final pressure = 0.447 atm
Final volume = ?
Solution:
The given problem will be solved through the Boyle's law,
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
by putting values,
P₁V₁ = P₂V₂
0.926 atm × 457 mL = 0.447 atm × V₂
V₂ = 423.18 atm. mL/ 0.447 atm
V₂ = 946.72 mL
Answer:
Thus, the radius of the helium atom in nanometers is - 0.031 nm
Explanation:
Given that:-
The radius of the helium atom = 31 pm
Considering the conversion of length in pm to the length in nm as:-
1 pm = 0.001 nm
So,
Applying the above conversion factor in the radius of helium atom as:-
Radius = 
nm = 0.031 nm
<u>Thus, the radius of the helium atom in nanometers is - 0.031 nm</u>
Answer:
<u>Radiation is the transfer of energy by waves, and conduction is the transfer of heat through contact with air.</u>
Explanation:
Conduction is the transfer of thermal energy through direct contact. Radiation is the transfer of thermal energy through thermal emission.
Answer:
-125 kJ
Explanation:
You calculate the energy required to break all the bonds in the reactants. Then you subtract the energy to break all the bonds in the products.
H₂C=CH₂ + H₂ ⟶ H₃C-CH₃
Bonds: 4C-H + 1C=C 1H-H 6C-H + 1C-C
D/kJ·mol⁻¹: 413 612 436 413 347
The formula relating ΔHrxn and bond dissociation energies (D) is
ΔHrxn = Σ(Dreactants) – Σ(Dproducts)
(Note: This is an exception to the rule. All other thermochemical reactions are “products – reactants”. With bond energies, it’s “reactants – products”. The reason comes from the way we define bond energies.)
<em>For the reactant</em>s:
Σ(Dreactants) = 4 × 413 + 1 × 612 + 1 × 436 = 2700 kJ
<em>For the products:</em>
Σ(Dproducts) = 6 × 413 + 1 × 347 = 2825 kJ
<em>For the system</em>
:
ΔHrxn = 2700 - 2825 = -125 kJ
