Answer:
All of the above processes have a ΔS < 0.
Explanation:
ΔS represents change in entropy of a system. Entropy refers to the degree of disorderliness of a system.
The question requests us to identify the process that has a negative change of entropy.
carbon dioxide(g) → carbon dioxide(s)
There is a change in state from gas to solid. Solid particles are more ordered than gas particles so this is a negative change in entropy.
water freezes
There is a change in state from liquid to solid. Solid particles are more ordered than liquid particles so this is a negative change in entropy.
propanol (g, at 555 K) → propanol (g, at 400 K)
Temperature is directly proportional to entropy, this means higher temperature leads t higher entropy.
This reaction highlights a drop in temperature which means a negative change in entropy.
methyl alcohol condenses
Condensation is the change in state from gas to liquid. Liquid particles are more ordered than gas particles so this is a negative change in entropy.
Answer:
- <u>No, you cannot dissolve 4.6 moles of copper sulfate, CuSO₄, in 1750mL of water.</u>
Explanation:
This question is part of a Post-Lab exercise sheet.
Such sheet include the saturation concentrations for several salts.
The saturation concentration of Copper Sulfate, CuSO₄, indicated in the table is 1.380M.
That means that 1.380 moles of copper sulfate is the maximum amount that can be dissolved in one liter of solution.
Find the molar concentration for 4.6 moles of copper sulfate in 1,750 mL of water.
You need to assume that the volume of water (1750mL) is the volume of the solution. This is, that the 4.6 moles of copper sulfate have a negligible volume.
<u>1. Volume in liters:</u>
- V = 1,750 mL × 1 liter / 1,000 mL = 1.75 liter
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<u>2. Molar concentration, molarity, M:</u>
- M = number of moles of solute / volume of solution in liters
- M = 4.6 moles / 1.75 liter = 2.6 M
Since the solution is saturated at 1.380M, you cannot reach the 2.6M concentration, meaning that you cannot dissolve 4.6 moles of copper sulfate, CuSO₄ in 1750mL of water.
Answer:
A. How much decay happens in each flashlight
Explanation:
In an experiment, the DEPENDENT OR RESPONDING VARIABLE is the variable that responds to changes being made to another variable called Independent variable. It is the variable that is measured by an experimenter.
In this question, an experiment was carried out to research the effect of sunlight on plastic decay. Three plastic flashlights were used for this experiment in which one was placed in a dark closet (control), and the others were placed in light at different times or intervals. However, the variable being measured or assessed is the decay of each flashlight. This means that "HOW MUCH DECAY HAPPENS IN EACH FLASHLIGHT" is the dependent variable.
They become an ionic bond, and are weakly bonded compared to covalently bonded atoms
