Answer:
A decrease in temperature decreases the number of collisions between molecules . The reaction rate will decrease
Explanation:
For each process, predict the sign on the entropy change and write a sentence or two to explain how to make this prediction without completing any mathematics. a.A solid melts. b.A vapor is converted into a solid. CH 117 Recitation Name: _________________________________ ~ 196 ~ c.A liquid freezes. d.A solid sublimes e.A vapor condenses to a liquid. f.A liquid boils. g.Dissolving a tablespoon of salt in water. h.Combustion of gasoline.
Answer: a. A solid melts: [tex]\Delta S=+ve[/tex]
b. a vapor is converted to solid: [tex]\Delta S=-ve[/tex]
c. a liquid freezes: [tex]\Delta S=-ve[/tex]
d. A solid sublimes: [tex]\Delta S=+ve[/tex]
e. a vapor condenses to liquid : [tex]\Delta S=-ve[/tex]
f. a liquid boils: [tex]\Delta S=+ve[/tex]
g. dissolving a tablespoon of salt in water: [tex]\Delta S=+ve[/tex]
h. combustion of gasoline: [tex]\Delta S=+ve[/tex]
Explanation:
Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy change is negative and vice versa.
a. A solid melts: The solid is converting to liquid, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
b. a vapor is converted to solid: The gas is converting to solid, thus the randomness is decreasing as the molecules are moving close and the intermolecular forces are getting stronger Thus the entropy change [tex](\Delta S)[/tex] is negative.
c. a liquid freezes: The liquid is converting to solid, thus the randomness is decreasing as the molecules are moving close and the intermolecular forces are getting stronger. Thus the entropy change [tex](\Delta S)[/tex] is negative.
d. A solid sublimes: The solid is converting to gas, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
e. a vapor condenses to liquid : The gas is converting to liquid, thus the randomness is decreasing as the molecules are moving close and the intermolecular forces are getting stronger. Thus the entropy change [tex](\Delta S)[/tex] is negative.
f. a liquid boils: The liquid is converting to gas, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
g. dissolving a tablespoon of salt in water: The solid is converting to ions , thus the randomness is increasing as the ions can move freely. Thus the entropy change [tex](\Delta S)[/tex] is positive.
h. combustion of gasoline: The liquid is converting to gas, thus the randomness is increasing as the molecules are moving away and the intermolecular forces are getting weaker. Thus the entropy change [tex](\Delta S)[/tex] is positive.
A wave travels at 22 m/s and has a wavelength of 11 m. What is its frequency
The answer is 2Hz
To calculate frequency, divide the number of times the event occurs by the length of time.
explain what is ment by solvent front
Answer:
In paper chromatography, the wet moving edge of the solvent that progresses along the surface where the separation of the mixture is occurring.
Explanation:
I hope this helps and pls mark me brainliest :)
3.88g of NaOH is required to neutralize a spill of hydrochloric acid. A 0.516M solution of NaOH is available for use.
A. Determine the number of moles needed to complete the reaction.
B. What volume of NaOH solution is needed for this reaction?
C. What volume of a stock 1,15M solution would be used to make the solution used in the reaction?
Answer:
ftb
Explanation:
What would
happen to the
vultures if the
gazelle
decreased?
Answer: If the gazelle population starts to decrease this could lead to some vultures not having enough food to eat
Explanation: This explains the obvious outcome of what would happen.
Hope you do well with what your doing :)
Mark as Brainliest please :)
Psychology is the study of the human brain. A psychoanalyst is a person who
analyzes people's minds. What does the prefix psycho-mean?
A. Related to the brain
B. Related to studying
C. Related to science
D. Related to analysis
What is a renewable resource on Earth?
minerals
coal
wind
petroleum
Answer:
Wind
Explanation:
Wind turbines make energy by the movement of the natural force on earth called 'wind' and renewable resources are resources that can be made from natural and environment-safe objects or things (e.g. Water, Geothermal Heat, The Sun, and Wind)
the color of an object that absorbs all colors except red
Answer:
The color black absorbs most colors, while white reflects most colors.
What is the cation in KF?
Answer:
K, or Potassium
Explanation:
There is a bottle of KCl solution: the volume is 35 mL; its molarity is 3.0 M.
After diluting it into final volume 200 mL, what is the molarity (in M) now?
Answer:
0.525 M
Explanation:
As the problem deals with a dilution process, we can use the following formula:
C₁V₁=C₂V₂Where subscript 1 stands for initial concentration and volume, while 2 stands for the final conditions. Meaning that in this case:
C₁ = 3.0 MV₁ = 35 mLC₂ = ?V₂ = 200 mLWe input the data given by the problem:
3.0 M * 35 mL = C₂ * 200 mLAnd solve for C₂:
C₂ = 0.525 M
24. A wave has a speed of 50 m/sec. If its frequency is 100 Hz,
what is its wavelength?
Answer:
I guess
Wave speed= Frequency x Wavelength
-> Wavelength= Wave speed divide Frequency
-> 50m/s divide 100Hz= 0.5m
I hope it help! :)
A gas under a pressure of 9.86 kPa and at a temperature of 75°C occupies a 500.0L container. How many moles of gas are in the container?
Answer:
1.7 mol
Explanation:
This is an ideal gas problem. So many units! That's the tip-off usually.
PV=nRT
First convert kPA to atm 1 atm=101.3 kPA so 9.86/101.3 = .097311 atm
(.097311 atm x 500L) = n · 0821 L·atm/mol·K · 348K
Do your multiplication then divide to get n alone and you should get 1.7 mol
a freshwater stream flows into the ocean as shown in the diagram which statement correctly describes how the stream affects these salinity of the ocean
A- salinity increases because the stream adds salt to the ocean.
B- salinity decreases because the stream adds freshwater to the ocean
C- salinity increases because of stream adds freshwater to the ocean
D- salinity Remains the Same because the stream adds freshwater to the ocean
Q3: Match the column A with Column B and write answer in Column C
Answer:
ok
Explanation:
1d
2c
3b
4a
What transition energy corresponds to an absorption line at 502 nm?
A. 4.56 x 10-19
B. 1.76 10-19
C. 2.53 x 10-19
D. 3.96 10-19 J
Answer:
D 3.96 10-19J
Explanation:
I took the test
Please Need help asap
For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have?
А. 13
B. 14
C. 26
D. 27
E. 40
Answer:
A
Explanation:
The number of protons and neutrons of an element is the same. the electrons are the only thing that can differ. The atomic number equal the protons and neutrons.
A coffee cup calorimeter will not be used to
directly measure the enthalpy of magnesium
combustion because
✓ the coffee cups could melt.
The calorimeter is made of coffee cups instead of
a beaker because coffee cups are
✓ better insulators
than beakers.
You will not measure the enthalpy of the reaction
of
✓ H2 and 02
in the coffee cup calorimeter because this reaction involves gases
Instead, you will use a well-known published
value.
These are the correct answers on edge 2021
Answer:
Ingles porfavor
Explanation:
The calorimeter is used to measure the heat of the system. The enthalpy of the combustion of magnesium cannot be measured by the calorimeter as it could melt the cup.
What is a coffee cup calorimeter?A coffee cup calorimeter is a styrofoam cup that contains partially filled water and is dipped with a thermometer. The reaction occurs in the water of the cup and hence differs from the bomb calorimeter.
The enthalpy of combustion is rigorous which can dissolve the polystyrene cup and hence is not used. They are better insulators than a beaker. The coffee cup calorimeter is not used to measure the enthalpy of hydrogen and oxygen as they involve gases that can escape the cup.
Learn more about coffee cup calorimeter here:
https://brainly.com/question/4390364
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How are cells organized?
A: Organs
B: Organelles
C: Tissues
Answer:
tissues,organs, organelles
1.
Why are kilometers not a good unit of measurement in space?
T.
2.
What distance measurement unit is used for objects within our solar system?
astronomical
units
3.
How many kilometers are in one astronomical unit?
4.
What distance measurement unit is used for objects outside of our solar
system?
_light
year!
5.
How many kilometers are in one light-year? I
How far away is the nearest star to Earth other than our Sun?
6.
7.
How far away is the center of the Milky Way Galaxy from Earth?
8.
What is the diameter of the Milky Way Galaxy?
HELP PLEASEEEEEE ASAP
A condition in which bones become weak and brittle.
The body constantly absorbs and replaces bone tissue. With osteoporosis, new bone creation doesn't keep up with old bone removal.
thus 2) is correct.
a disease in which bone tissue becomes breakable and thin.
if it helps don't forget to like and Mark me
is pyramidal molecular geometry?
A. N2
B. H2O
C. NH3
D. CCL4
Answer:
[tex]\color{Blue}\huge\boxed{Question} [/tex]
Is pyramidal molecular geometry?[tex]\color{Blue}\huge\boxed{Answer} [/tex]
B.H2OWhat volume would 75.0g of oxygen gas occupy
Answer:
Explanation: It is already known that 1 mole of the gas( or 32g of O2) is equivalent to 22.4 Litres of the oxygen gas. So, 8g is equivalent to = (22.4/32) × 8 = 5.6 L of the gas.
Question 10
1 pts
Given the following balanced chemical equation:
2C2H10 + 902 +4CO2 + 10H2O
How many grams of C2H10 are needed to produce 150. g of water?
396 g
15.8 g
O 1420
O 56.8 g
Answer:
56.8 g
Explanation:
Your first conversion factor is the molar mass of H2O to convert from grams of water to moles. Your second conversion factor is the mole ratio of 2 mol C2H10 for every 10 mol H2O. Your last conversion factor is the molar mass of C2H10 to convert from moles back to grams.
150. g H2O • (1 mol H2O / 18.02 g H2O) • (2 mol C2H10 / 10 mol H2O) • (34.1 g C2H10 / 1 mol C2H10) = 56.8 g C2H10
3.
The color of the powdered form of a mineral is called
O fracture
O cleavage
O luster
O streak
Answer:
D. Streak.
Explanation:
A mineral, in simple terms, can be defined as a solid inorganic substance that occurs in a pure form with a specific crystal structure. A mineral is identified based on its physical properties which include luster, color, streak, crystal shape, etc.
The color of the powdered form of a mineral is called a streak. A streak is a useful property in distinguishing sulfide and oxide minerals. To check the color of a mineral, it is rubbed against the surface of a ceramic streak plate or a piece of unglazed ceramic. In its finely powdered form, a mineral is easy to identify.
Therefore, option D is correct.
Why are half-reactions used in redox reactions?
Answer:
Because a redox reaction holds for both oxidation and reduction.
One half equation is of oxidation and the other is of reduction.
When these two half equations are combined, we get an overall equation of the redox reaction.
3.
Why do you suppose internet service costs a lot of money?
Answer:
Why does internet cost so much? Equipment and installation: One of the main reasons for internet prices to run high is the cost of equipment and installation in new service areas. Fiber optic cables are expensive, so fiber optic internet providers may have higher prices to recoup the costs of installing new lines.Apr 21, 2021Explanation:
What is the energy of an electron in a Li+ ion when an electron moves from n = 2 to n =3?
Ali says the climate of a town is rainy because it is raining outside today. Is she correct? In one or two sentences, explain why Ali is or is not correct about the climate of the town.
Answer:
Ali is incorrect.
Explanation:
Ali is wrong because the climate is a study of the weather pattern over a long period of time. You cannot look outside one day and determine the climate because the climate is long-term.
She could say the weather is rainy, because that is short term, but not the climate.
A buffer solution is 0.439 M in CH3COOH and 0.311 M in CH3COONa . If K_a for CH2COOH is 1.8x10^-5, what is the pH of this
buffer solution?
Please no link answers!
Answer:
whats CH3COOH please tell me so I can answer!
Iodine shines like metals but is not metal what is its basis
Answer:
Iodine is a non-metal, but it is lustrous (lustrous is the property of metal) in nature.