Answer. Answer: Scientists study how things work, while engineers create new things
Answer:
Batteries store chemical energy
Explanation:
option A.
The number of valence electrons of an element can be determined by the periodic table group (vertical column) in which the element is categorized
What ozone layer do we live in?
Answer: We live in the troposphere. There are 4 ozone layers: Troposphere, Stratosphere, mesosphere and atmosphere(of course)
The troposphere is the first layer<span> above the surface and contains half of the </span>Earth's atmosphere<span>. Weather occurs in this </span><span>lay</span>
Answer:
You must remove
.
Explanation:
There are three heat transfers in this process:
Total heat = cool the vapour + condense the vapour + cool the liquid
q = q₁ + q₂ + q₃
q = nC₁ΔT₁ + nΔHcond + nC₂ΔT₂
Let's calculate these heat transfers separately.
Data:
You don't give "the data below", so I will use my best estimates from the NIST Chemistry WebBook. You can later substitute your own values.
C₁ = specific heat capacity of vapour = 90 J·K⁻¹mol⁻¹
C₂ = specific heat capacity of liquid = 115 J·K⁻¹mol⁻¹
ΔHcond = -38.56 kJ·mol⁻¹
Tmax = 300 °C
b.p. = 78.4 °C
Tmin = 25.0 °C
n = 0.782 mol
Calculations:
ΔT₁ = 78.4 - 300 = -221.6 K
q₁ = 0.782 × 90 × (-221.6) = -15 600 J = -15.60 kJ
q₂ = 0.782 × (-38.56) = -30.15 kJ
ΔT = 25.0 - 78.4 = -53.4 K
q₃ = 0.782 × 115 × (-53.4) = -4802 J = 4.802 kJ
q = -15.60 - 53.4 - 4.802 = -50.6 kJ
You must remove
of heat to convert the vapour to a gas.