Answer:
The answer is Observation.
For you to observe the things around you then you need to use all your sense organs....
H₂O + H₂O ⇌ H₃O⁺ + OH⁻
You use two single-barbed arrows pointing in opposite directions (technically rightwards harpoon over leftwards harpoon) <em>to indicate a reversible reactio</em>n.
Answer:
Epidermis
Explanation:
The epidermis lacks blood vessels.
Answer:
B- Lower temperature causes a reduction in movement
Explanation:
When heat is added to a substance, the molecules and atoms vibrate faster. As atoms vibrate faster, the space between atoms increases. The motion and spacing of the particles determines the state of matter of the substance. The end result of increased molecular motion is that the object expands and takes up more space
Answer:
The total heat required is 4088.6 J
Explanation:
We have three processes which involve heat absorption. We have to calculate the heat of each process and then to calculate the total heat.
1- liquid ethanol is heated from 25ºC (298 K) to the boiling point 78.5ºc (351.5 K). We use specifi heat of liquid ethanol to calculate the heat absorbed in this part:
H1= m x Sh x ΔT
H1= m x Sh x (Tfinal - Tinitial)
H1= 3.95 g x 2.45 J/g.K x (351.5 K -298 K)
H1= 517.7 J
2- State change: liquid ethanol is vaporized it turns gaseous ethanol The process occur at constant temperature (78.5ºC= 351.5 K). We need the molecular weight of ethanol (2 x 14 + 5 + 16 + 1= 46 g/mol) to cancel mol unit:
H2= m x ΔHvap x 1/Mw
H2= 3.95 g x 40.5 KJ/mol x 1 mol/46 g
H2= 3.477 KJ= 3477 J
3- Gaseous ethanol is heated from 78.5ºC to a final temperature of 95ºC (368 K). We use the specific heat of gaseous ethanol:
H3= m x Sh x ΔT
H3= 3.95 g x 1.43 J/g.K x (368 K - 351.5 K)
H3= 93.2 J
The total heat required is calculated as follows:
Htotal= H1 + H2 + H3
Htotal= 517.7 J + 3477.7 J + 93.2 J
Htotal= 4088.6 J
