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.
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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.
7. Which of the following is a proof that light travels in a straight line?
A. Formation of clouds
C. Formation of rainbows
B. Formation of colors
D. Formation of shadow
Answer:
formation of shadow is right
Answer:
correct answer is D
Explanation:
When you see a shadow, it is directly behind the object.
A student prepares a aqueous solution of butanoic acid . Calculate the fraction of butanoic acid that is in the dissociated form in his solution. Express your answer as a percentage. You will probably find some useful data in the ALEKS Data resource.
Answer:
15.4%
Explanation:
If Ka = 0.54 mM = 1.51x10⁻⁵
Then;
C₄H₈O₂ --------> C₄H₇O₂⁻ + H⁺
I 0.54x10⁻³ 0 0
E 0.54x10⁻³(1-x) 0.54x10⁻³x 0.54x10⁻³x
Recall that x is the percentage degree of dissociation
From the ICE table;
Ka = [C₄H₇O₂⁻] [ H⁺]/[C₄H₈O₂]
1.51x10⁻⁵=(0.54x10⁻³x) (0.54x10⁻³x)/ 0.54x10⁻³(1-x)
1.51x10⁻⁵ = 0.54x10⁻³x^2/1-x
1.51x10⁻⁵(1-x) = 0.54x10⁻³x^2
1.51x10⁻⁵ - 1.51x10⁻⁵x = 0.54x10⁻³x^2
Hence;
0.54x10⁻³x^2 + 1.51x10⁻⁵x - 1.51x10⁻⁵=0
x^2 + 0.028x - 0.028 = 0
Solving the quadratic equation here;
x = 0.154 or −0.182
Ignoring the negative result, x = 0.154
Hence, fraction of butanoic acid that is in the dissociated form in this solution = 15.4%
Explain in detail how low density polyethylene is made
Answer:
Low-density polyethylene is manufactured by the process of the polymerization of ethylene at very high temperatures in a tubular reactor. In this tubular reactor, high-pressure polymerization allows further copolymerization of ethylene with polar co-monomers. The tubular process has an advantage over autoclave process.
Explanation:
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WILL AWARD BRAINLIEST! I NEED HELP PLEASE! Match the states of matter for each of the five lines below.
Answer:
see explanations
Explanation:
The graphic is the heating curve for water. Note that it is divided into 5 distinct heat flow segments. The segments with changing slopes are single phase segments with changes in temperature values. From left to right segment A is solid ice being warmed to it's melting point. Segment B is the melting segment in which 2 phases are in contact (solid + liquid). Note that addition of heat does not change the temperature. Segment C is warming of the liquid (single phase) up to its boiling point. At the boiling point the liquid begins to pass into the gas phase and again 2 phases are in contact; i.e., liquid & gas. Note again when two phases are in contact no temperature change occurs. Finally, segment E is the heating of the pure, single phase gas.
In summary ...
Segment A => heating single phase (solid) ice up to melting pt.
Segment B => melting of ice => 2 phases in contact (s & l) ΔT = ∅.
Segment C => heating single phase (liquid) water up to boiling pt.
Segment D => boiling of liquid => 2 phases in contact (l & g). ΔT = ∅.
Segment E => heating single phase (steam) up to desired temperature.
For what it's worth, the equation for the segments that show increasing temperature values is q = mcΔT (m= mass, c = specific heat & ΔT temp change.
The segments with zero slopes (horizontal lines) are defined by equations q = m·ΔHₓ where m = mass & ΔHₓ = heat of fusion (a constant = 335 j/g). The same is true for the line at 100°C where q = m·ΔH(v) where m = mass & ΔH(v) is the heat of vaporization (a constant = 2259 j/g.
Calculations involve calculating the amount heat transfer for each segment individually and then adding the heat values to obtain the total heat transfer.
If you need more instruction on this topic, kick back a note and I'll try to help clarify. Good Luck, Doc :-)
Answer:
Picture attached has answers
Explanation:
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:
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What is the air pressure on top of the mountain?
Explanation:
At sea level, the atmospheric pressure would be a little over 100 kPa (one atmosphere or 760 mm Hg). If we climb to the top of Mount Everest (the highest mountain in the world at 29,029 feet or 8848 meters), the atmospheric pressure will drop to slightly over 30 kPa (about 0.30 atmospheres or 228 mm Hg).
Hope it is helpful for you
In the process of photosynthesis, sunlight is converted into
Answer:
Chemical energy
Explanation:
By the use of electrons and protons from water
Answer:
chemical energy
Explanation:
Photosynthesis is the process by which organisms that contain the pigment chlorophyll convert light energy into chemical energy which can be stored in the molecular bonds of organic molecules (e.g., sugars). Photosynthesis powers almost all trophic chains and food webs on the Earth.
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 MIodine 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.
true or false atoms can be made up of just one type of atom
Answer:
false
Explanation:
A compound has the combined properties of the elements from which it is made. Atoms show the macro properties of an element.
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:
Describe two realistic demands protestors could bring forward in their peaceful protest so that they dont face the same situation in future
Answer:
I do not know the Answer I'm just trying to get my point
Explanation:
Thank You
The two realistic demands protestors could bring forward in their peaceful protest include:
Adequate securityProvision of social amenities.Who is a Protester?Thus it is referred to an individual which publicly demonstrates opposition to something.One of the roles of the government is to protect lives and properties.
Making realistic demands during a peaceful protest is looked into in most cases.
Read more about Protester here https://brainly.com/question/11505871
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:
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SO2 + PCL5 → SOCL2 + POCL3
What mass of SOCL2 is produced when 1.35 g SO2 react with 2.75 g PCL5
Answer:
2.34
Explanation:
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)
Electrophilic substitution occurs
Answer:
I hope it's helpful for you....
Explanation:
Electrophilic substitution reactions are chemical reactions in which an electrophile displaces a functional group in a compound, which is typically, but not always, a hydrogen atom.
23. Forces accelerate objects. Newton's second law state that force equals ______times?
Answer:
F = ma, or force is equal to mass times acceleration.
How many mL of 0.100M Ca(OH) are needed to titrate 20.0mL of 0.300M H2SO4
Answer:
60.0 mL
Explanation:
Using CAVA = CBVB
CA = 0.300M
VA = 20.0 mL
CB = 0.100M
VB = ?
VB = CAVA
CB
VB = 0.300 * 20/ 0.100
VB = 60.0 mL
What physical property of matter determines the earth ?
Answer:
Density is a physical property that is determined by dividing the mass of a given amount of a substance by its volume.
Explanation:
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.
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.
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.
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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?
Which product will precipitate in the following reaction:
CaCl2 + Na2CrO4 → CaCrO4 + 2 NaCl
A.NaCl
B.CaCrO4
C.Na2CrO4
D.CaCl2
Answer:
a
Explanation:
Determine the molar mass of a compound that has a density of 1.25 g/L at
STP. *
*
Answer:
So, weight per litre (1.25g/l) times 22.4 l/mole equals the mole weight (28 g/mole).
A mixture of NO2 and N2O4 gas is at equilibrium in a closed container. These gases react with the equation 2NO2 ⇌ N2O4. What will happen if the size of the container is increased?
Answer:
Equilibrium will shift leftwards towards NO2.
Explanation:
Hello there!
In this case, according to the Le Cha telier's principle, it is possible to realize that the increase of the volume turns out in the shift towards the most of the gaseous moles are in; in such a way, for the given chemical reaction, we can notice how NO2 (reactant side) has the most of the moles (2 moles in comparison to 1 mole of N2O4); and therefore, by increasing the volume, the equilibrium will shift to it, it means leftwards.
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how is the periodic table important for all of science and not just chemistry? pleas answer me
Answer:
The periodic table has been there for such a long time and how it is helpful in all science it is the element itself. How the element is used in real life. For example, oxygen is used in the atmosphere. Plants use carbon in order to covert it into oxygen more like that
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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.
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