Answer:
The temperature should be higher than 437.9 Kelvin (or 164.75 °C) to be spontaneous
Explanation:
<u>Step 1:</u> Data given
ΔH∘=20.1 kJ/mol
ΔS is 45.9 J/K
<u>Step 2:</u> When is the reaction spontaneous
Consider temperature and pressure = constant.
The conditions for spontaneous reactions are:
ΔH <0
ΔS > 0
ΔG <0 The reaction is spontaneous at all temperatures
ΔH <0
ΔS <0
ΔG <0 The reaction is spontaneous at low temperatures ( ΔH - T*ΔS <0)
ΔH >0
ΔS >0
ΔG <0 The reaction is spontaneous at high temperatures ( ΔH - T*ΔS <0)
<u>Step 3:</u> Calculate the temperature
ΔG <0 = ΔH - T*ΔS
T*ΔS > ΔH
T > ΔH/ΔS
In this situation:
T > (20100 J)/(45.9 J/K)
T > 437.9 K
T > 164.75 °C
The temperature should be higher than 437.9 Kelvin (or 164.75 °C) to be spontaneous
Answer:
Many plants have thorns on their stems or leaves. What is the MOST likely explanation for the evolution of thorns?
A) Thorns help plants produce more food from photosynthesis.
B) Thorns are an example of a mutation that arises in the genetic code of plants.
C) Thorns help plants to conserve resources like water and soil nutrients that may be used by other organisms.
D) Thorns are an adaptation that some plants have evolved in order to discourage herbivores from eating the plant.
2)
Explanation:
Answer:
Species
Explanation:
Species is the group of organisms able to interbreed and produce fertile offspring.
Let's break down each word in the question:
"Organisms" means living thing. It can be a plant or animal like we usually think of, but it also includes the really small single-celled living things like some bacteria.
"Interbreed" means to mate with each other.
"Fertile" means that the living thing can also have babies.
"Offspring" means the children that are born.
"Fertile offspring" means that the children that are made must be able to have babies of their own. For example, if a frog and a bird could interbreed, they might produce offspring (children). But, if those frog-birds cannot also have children, then frog-bird is not a species.
Question:
The options are;
a. Temperature
b. Thermal Energy
c. Hotness
d. Fire Energy
Answer:
The correct option is;
b. Thermal energy
Explanation:
A burner on a stove produces thermal energy which is used to raise the temperature of the metal container (kettle, pot or pans) in which items are placed for heating.
Thermal energy is the internal energy of the system given off as heat which when transferred from one body to another causes the temperature of the receiving body to rise. Thermal energy in a burner is given off when the gaseous fuel reacts or burns in the presence of or with oxygen to produce carbon dioxide and water vapor in an exothermic reaction.
4C + 5H₂ + 13/2O₂ (-125 kJ) → C₄H₁₀ + O₂ → CO₂ + H₂O (-2877 kJ).
The flow of electricity is an electric current. The path that an electric currents floes is a circuit.
