All the elements you listed share a common trait: they are synthetic, radioactive elements. These elements do not have a stable isotope, so for a radioactive element, its most stable isotope's atomic mass will be listed in parentheses.
One such example would be plutonium. This element has 6 different isotopes with differing half-lives. The most stable isotope for plutonium is plutonium-244, with a half-life of around 80 million years. Therefore, the atomic mass listed for plutonium will be (244).
Students of diffrent ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle
Do you want to know the times
witch components of the atom are found outside of the nucleus
A protons
B electrons
C neutrons
B all
What happens when an atom loses electron?
what are the slope and the y-intercept of the linear function that is represented by the equation y=-10X+1 ?
The slope is 10
And the y-intercept is 1
Hope it helps
What is the term given to the penetrating rays and particles given off by radioactive materials called
Answer: The penetrating rays and particles given off by radioactive materials is called radiation.
Explanation:
The penetrating rays and particles given off by radioactive materials is called radiation.
An element which readily degenerates its nucleus and emits alpha particles, beta particles and gamma rays is called a radioactive element.
For example, uranium, actinium, thorium etc are all radiactive elements.
Which best describes the order of the technology used to transmit a sound through the radio
The correct answer is "microphone - transmitter - radio"
The order of the technology used to transmit a sound through the radio which makes use of electromagnetic waves is microphone - transmitter - radio".
What are electromagnetic waves?The electromagnetic radiation consists of waves made up of electromagnetic field which are capable of propogating through space and carry the radiant electromagnetic energy.
The radiation are composed of electromagnetic waves which are synchronized oscillations of electric and magnetic fields . They are created due to change which is periodic in electric as well as magnetic fields.
In vacuum ,all the electromagnetic waves travel at the same speed that is with the speed of air.The position of an electromagnetic wave in an electromagnetic spectrum is characterized by it's frequency or wavelength.They are emitted by electrically charged particles which undergo acceleration and subsequently interact with other charged particles.
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A piece of metal of mass 26 g at 117◦C is placed in a calorimeter containing 56 g of water at 25◦C. The final temperature of the mixture is 58.7◦C. What is the specific heat capacity of the metal? Assume that there is no energy lost to the surroundings.
Answer in units of J . g ·◦ C
Step 1) Determine the amount of energy the water absorbed, or gained, using q= mc∆T
q=(56g)(4.184 J/g°c)(58.7-25)
q=+7896.0448 J
Step 2) Let's think about what this means. The water must have gained 7896.0448 J of energy because its energy is positive.
This makes sense too, since the temperature of the water increased, and thus it must have gained energy. Knowing this, we can conclude that the metal placed into the water must have released 7896.0448 J of energy.
Since we know the metal released 7896.0448 J of energy, when we solve for the specific heat capacity of the metal, we have to put this number in as negative.
Step 3) Using q= mc∆T, solve for the specific heat capacity of the metal
-7896.0448 J=(26g)(c)(58.7-117)
c=5.209160047 J/g°c
ANSWER: the specific heat capacity of the metal is 5.2 J/g°c
A student added 32.60 mL of 0.03020 M NaOH to a 20.0 mL sample of ginger ale before his sample turned pink. (a) How many moles of NaOH did he add to his solution? (b) How many moles of citric acid are in his sample? (c) How many grams of citric acid does this correspond to? (d) How many milligrams? How many mg/mL?
Solution:
molarity= [tex]\frac{\text{moles}}{\text{volume in litres}}[/tex]
(a) Molarity of NaOH, [tex]M_1[/tex]= 0.03020 M
Volume of NaOH added,[tex]V_1[/tex]= 32.60 mL= 0.0326 L
(1L= 1000mL)
Number of moles of NaOH added :
0.03020 M NaOH means 1L of solution contains 0.03020 moles 0.0326 L contains =[tex]0.03020\times 0.0326[/tex] = 0.00098 moles
(b) Equal number of moles of acid will neutralize equal number of moles of base, thus we can apply molarity equation:
Molarity of citric acid, [tex]M_2[/tex]=?
volume of citric acid, [tex]V_2[/tex]= 20 mL= 0.02 L
using formula, [tex](M_1)(V_1)=(M_2)(V_2)[/tex] ,
[tex]M_2= \frac{(M_1)(V_1)}{(V_2)}[/tex]
[tex]M_2= \frac{(0.03020 M)(0.0326 L)}{(0.02 L)}[/tex] = 0.049 M
(c) Grams of citric acid in 20 ml
moles of citric acid = [tex]{M_2}\times V_1[/tex] of solution in Liters = [tex]0.049 \times 0.02[/tex] = 0.00098 moles
Mass of citric acid =[tex]\text{moles}\times \text{Molecular} mass[/tex]
[tex]= 0.00098\times 192.12[/tex] = 0.1882 g
(d) 20 mL solution of ginger ale contains of citric acid
[tex]0.1882 g= 0.1882 \times 1000 mg[/tex] = 188.2 mg (1g = 1000mg)
Since, 20 mL solution of ginger ale contains of citric acid 188.2 mg
so 1 mL of solution contains = [tex]\frac{188.2 mg}{20 mL}[/tex]
= 9.41 mg/ mL
(a)
Molarity = moles of solute / liter of solution
Moles of solute = molarity x liter of solution
Molarity of NaOH = 0.03020 M
Liter of solution = 32.60 mL / 1000 = 0.0326 L
Moles of NaOH = 0.03020 M x 0.0326 L = 9.85 x 10⁻⁴ moles
(b)
The reaction between NaOH and citric acid is as follows:
C₃H₅O(COOH)₃ + 3NaOH → Na₃C₃H₅O(COO)₃ + 3H₂O
As the balanced chemical equation 3 moles of NaOH reacts with 1 mole of citric acid (Na₃C₃H₅O(COO)₃)
Since the moles of NaOH is 9.85 x 10⁻⁴ the moles of citric acid will be (9.85 x 10⁻⁴) / 3 or 3.284 x 10⁻⁴ moles.
Therefore, the moles of citric acid is 3.284 x 10⁻⁴
(c)
Moles = Mass/ Molar mass
Mass = Moles x Molar mass
Moles of citric acid = 3.284 x 10⁻⁴
Molar mass of citric acid = 192.124 g/mol
Mass of citric acid = 3.284 x 10⁻⁴ x 192.124 g/mol =
Therefore, the mass of citric acid is 0.0631 g
(d)
Mass of citric acid = 0.0631 g
1 g = 1000 mg
Therefore, mass of citric acid = 0.0631 x 1000 = 63.1 mg
(e)
Given,
Volume of citric acid = 20.0 mL
20 ml of citric acid has a mass of 63.1 mg
Therefore, miligram per militier = 63.1 mg/20 ml = 3.155 mg/ml
What is the mass of 2.70 moles of magnesium chloride, MgCl2?
First, calculate the molar mass of MgCl2:
Mg: 1 x 24.30 = 24.30
Cl: 2 x 35.45 = 70.9
24.30 + 70.9 = 95.2g/mol
Mole = Mass / Molar Mass
2.70 moles = Mass / 95.2 g/mol
Mass = 2.70 mol x 95.2 g/mol
Mass = 257.04g
Answer: The mass of magnesium chloride is 257.1 grams.
Explanation:
To calculate the mass of magnesium chloride for given number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
We are given:
Moles of magnesium chloride = 2.70 moles
Molar mass of magnesium chloride = 95.21 g/mol
Putting values in above equation, we get:
[tex]2.70moles=\frac{\text{Mass of magnesium chloride}}{95.21g/mol}\\\\\text{Mass of magnesium chloride}=(2.70mol\times 95.21g/mol)=257.1g[/tex]
Hence, the mass of magnesium chloride is 257.1 grams.
Where does the energy come from that is needed for an endothermic reaction
Where else but from the surroundings?
Answer : For an endothermic reaction the energy come from the surroundings.
Explanation :
Endothermic reaction : It is a type of chemical reaction in which the energy is absorbed by the surroundings. In this reaction, the energy of reactants are less than the energy of products. The energy of reactant is greater than the energy of product.
Exothermic reaction : It is a type of chemical reaction in which the energy is released into the surroundings. In this reaction, the energy of reactants are more than the energy of products. The energy of product is greater than the energy of reactant.
Hence, the energy come from the surroundings that is needed for an endothermic reaction.
which of the following correctly describes a compound
combination of elements on the periodic table to create a substance. so I think I understand about this okay but I have a 98% on that type of subject
Name the region of the atom where protons and neutrons are located. This region is indicated by label B. Name the region of the atom where electrons are located. This region is indicated by label A. Locations of Subatomic Particles
The region of the atom where protons and neutrons are located (B) is called the nucleus.
The region of the atom where electrons are located (A) is called orbits.
An atom is made up of electrons in orbits and protons and neutrons in the nucleus.
In the atom, there is an innermost part where we find the subatomic particles called neutrons and protons. This region of the atom is called the nucleus. Most of the mass of the atom is concentrated here.
The electrons are found to move round this nucleus in circular paths called orbits.
In the figure, label A refers to orbits while label B refers to the nucleus.
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Answer:
1st is Nucleus and 2nd is Orbitals
Explanation:
what is the only force that acts on a falling body when it is in free fall
As learned in an earlier unit, free fall is a special type of motion in which the only force acting upon an object is gravity. Objects that are said to be undergoing free fall, are not encountering a significant force of air resistance; they are falling under the sole influence of gravity.
Construct an explanation of how sodium and chlorine combine to form sodium chloride.
A) Chlorine metal loses a valence electron to become a cation and nonmetal sodium gains a valence electron to become an anion. These ions then form a bond through sharing valence electrons.
Eliminate
B) Nonmetal sodium loses a valence electron to become a cation and chlorine metal gains a valence electron to become an anion. These ions then form an ionic bond through opposite attraction.
C) Sodium metal loses a valence electron to become a cation and nonmetal chlorine gains a valence electron to become an anion. These then form a covalent bond through sharing valence electrons.
D) Sodium metal loses a valence electron to become a cation and nonmetal chlorine gains a valence electron to become an anion. These ions then form an ionic bond through electrostatic attraction.
The correct explanation is D.
Sodium being an Alkali Metal has a high tendency to lose its only valence electron to attain Neon configuration. In this process, it becomes positively charged, and hence becomes a Cation.
Chlorine is a non-metal that is one electron short of attaining Argon configuration, and hence readily takes the available electrons to become a negatively charged Anion. Since these two are oppositely charged, by the laws of electrostatics, they attract each other forming an Ionic Bond that requires considerable energy to break.
Answer:
the answer is d).
Explanation:
Which are examples of reversible reactions? Check all that apply.
Iodine and chlorine can react to form iodine chloride. At equilibrium, the system contains a mixture of iodine, chlorine, and iodine chloride.
Sodium hydroxide and hydrochloric acid react readily to form sodium chloride and water. The reverse reaction does not occur.
Hydrogen and nitrogen react to form ammonia. At low pressure, the equilibrium system contains all three substances.
Answer:
These first and the last are examples of reversible reactions:
Iodine and chlorine can react to form iodine chloride. At equilibrium, the system contains a mixture of iodine, chlorine, and iodine chloride.Hydrogen and nitrogen react to form ammonia. At low pressure, the equilibrium system contains all three substances.Explanation:
The reactions that end in a quasi complete conversion of the reactants into the products are said that are not reversible reactions.
Most of the chemical reactions do not reach a complete conversion. They seem to stop without getting complete conversion. The reason is that these reactions are reversible. A reversible reaction is that that can be forward (direct reaction) and backward (inverse or reverese reaction). In these cases, when the equilibrium is reached the rates of the forward and reverse reactions are equal, which explain why the reaction seems to stop, and a mixture of products and reactants will remain.
The two examples of reversible reactions given may be represented in this way:
The double arrow is used to indicate that the reaction is reversible. In the forward reaction, iodine and chlorine react to form iodine chloride, in the reverse reaction iodine chlorice decomposes to form the substances iodine and chlorine.
In the foward reaction, hydrogen a nitrogen combine to form amonia, in the reverse reaction ammonia decomposes producing the substances hydrogen and nitrogen.
Options 1 & 3 are correct! Thank you
3.01 Quiz: Atomic Number and the Periodic Law
ps
Which of the following characteristics was not included in Dmitri Mendeleev's periodic table?
distribution of elements determined by electron configuration
What is the primary atomic characteristic that Mendeleev used to organize the periodic table?
atomic mass
Mendeleev left several blank spaces in his original periodic table. What did those spaces represent?
elements that had yet to be discovered
According to the periodic law, what is the relationship between elements and periods?
Element properties repeat from period to period.
Which of these sets of elements has similar properties? Consult the periodic table.
strontium, magnesium, calcium, beryllium
Answer:
The answer is Dissemination of components controlled by electron design.
Explanation:
the Aufbau rule, the Pauli rejection guideline, and Hund's rule,tell you how to discover the electron designs of particles. As indicated by the aufbau standard, electrons possess the orbitals of most reduced vitality first, Pauli-prohibition rule, and Hund's Rule. The electronic setup of cations is doled out by evacuating electrons first in the peripheral p orbital, trailed by the s orbital lastly the d orbitals.
Extrusive formed igneous rocks cool faster and have larger crystals.
A- True
B- False
Answer these please! 23 points!
1. Why is hydrogen set apart by itself?
2. How do valence electron configurations of the alkali metals compare with each other?
3. Why are the alkaline-earth metals less reactive than the alkali metals?
4. In which groups of the periodic table do the transition metals belong?
5. What properties do the halogens have in common?
For the first question the answer is
The "s" orbital can only hold a maximum of two electrons. ... Elements in the each group have the same number of valence electrons. Why is hydrogen set apart by itself? Hydrogen does not belong to a single group b/c it can be considered an alkali metal, but it is also a gas.
1. Hydrogen is set apart by itself due to its unique properties that do not fit neatly into any specific group in the periodic table. 2. The alkali metals have similar valence electron configurations, each having one valence electron in their outermost energy level. 3. The alkaline-earth metals are less reactive than the alkali metals because they have two valence electrons in their outermost energy level, requiring more energy to lose them. 4. The transition metals belong to groups 3 to 12 in the periodic table, characterized by partially filled d orbitals in their electron configurations. 5. The halogens, belonging to group 17, share common properties like having 7 valence electrons, high reactivity, and forming acidic compounds when combined with hydrogen.
1. Hydrogen is set apart by itself because it does not fit neatly into any specific group in the periodic table. It has unique properties that are distinct from both the alkali metals and the halogens. While it can form positive ions like the alkali metals, it can also gain an electron to form negative ions like the halogens. Additionally, hydrogen can form covalent bonds with other elements, unlike the alkali metals and halogens. Due to these differences, hydrogen is considered a non-metal and is placed separately at the top of the periodic table.
2. The valence electron configurations of the alkali metals are similar as they all have one valence electron in their outermost energy level. For example, lithium has a valence electron configuration of 2s¹, sodium has 3s¹, potassium has 4s¹, and so on. This single valence electron makes the alkali metals highly reactive, as they readily lose it to form positive ions, achieving a stable electron configuration.
3. The alkaline-earth metals are less reactive than the alkali metals because they have two valence electrons in their outermost energy level. These electrons are held more tightly by the nucleus compared to the single valence electron of alkali metals. As a result, alkaline-earth metals require more energy to lose their valence electrons and become positive ions. While they are still reactive, they are not as reactive as the alkali metals.
4. The transition metals belong to groups 3 to 12 in the periodic table. These elements have partially filled d orbitals in their electron configurations, which gives them unique properties, such as forming colored compounds, being good conductors of electricity, and having high melting and boiling points. They are often used as catalysts in chemical reactions due to their ability to undergo multiple oxidation states.
5. The halogens have several properties in common. They belong to group 17 of the periodic table and have 7 valence electrons in their outermost energy level. Halogens are highly reactive non-metals, and they readily gain one electron to achieve a stable electron configuration. They have high electronegativity, making them strong oxidizing agents. Halogens exist as diatomic molecules in their elemental form (e.g., Cl₂, Br₂, I₂) and have a characteristic color and odor. Additionally, they form acidic compounds when combined with hydrogen, such as hydrochloric acid (HCl) and hydrofluoric acid (HF).
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BRAINLIEST IF CORRECT PLEASE USE WORK
2) what does the release or absorption of energy indicate?
a) physical and chemical changes
b) neither physical nor chemical changes
c) chemical change
d) physical change
The release or absorption of energy indicates a chemical change. (Option C).
What is chemical change?A chemical change, also known as a chemical reaction, is a process in which one or more reactants are transformed into new substances (products) with different chemical properties.
During a chemical change, the arrangement of atoms is altered, resulting in the formation of new chemical bonds and the breaking of existing ones.
This process often involves the release or absorption of energy in the form of heat, light, or other forms of energy.
Thus, the release or absorption of energy indicates a chemical change.
Option C is the correct answer.
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What does the specific heat for a substance indicate? A. the heat released when 1 gram of the substance burns B. the amount of heat required to increase the temperature of 1 gram by 1oC C. the amount of heat required to increase the temperature of 100 grams by 1oC D. the amount of heat required to increase the temperature of 1 gram by 100oC E. the heat released when 100 grams of the substance burns
Answer:
B. the amount of heat required to increase the temperature of 1 gram by 1°C
Explanation:
The heat required by a substance having mass m to raise the temperature of it by ΔT.
Q = m c ΔT
where c is the specific heat of the substance.
[tex] c = \frac{Q}{m\Delta T}[/tex]
Specific heat for a substance is the amount of heat required to increase the temperature of 1 gram by 1°C.
For example, the specific heat capacity of water is 4.186 J/g°C. This means 4.186 J is required to raise the temperature of 1 g of water by 1°C.
What is the difference between the atomic number and the mass number of an element?
Mass number is the number of protons and neutrons in an atom, and it tells us about the mass of the atom in amu, or atomic mass units. Atomic mass is the average mass of all the isotopes of a certain type. It is a weighted average that takes into account the abundances of all of the different isotopes
hope this helps :)
The difference between the atomic number and the mass number is atomic number is the total number of protons of an element, and atomic mass is the total number of neutrons and protons.
What are the atomic number and atomic mass?The atomic number is the nuclear charge number of an element. It is depicted by the total number of protons present in the atoms of the element.
The mass number is also known as the atomic mass number and nucleon number of the element. The total protons and neutrons are the mass numbers.
A mass number, also known as an atomic mass unit, is a measurement of an atom's mass in protons and neutrons. The average mass of all isotopes of a particular kind is known as the atomic mass.
Thus, the total number of protons in an element is represented by the atomic number, whereas the total amount of neutrons and protons is represented by the atomic mass.
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Select two options from the following list that qualify as types of pure substances. a substance an atom an element a particle matter a compound
Elements and compounds are examples of pure substances. Elements are made of one type of atom, while compounds consist of two or more types of atoms chemically bonded together.
Elements and compounds are both examples of pure substances.
Elements are the simplest substances made up of only one type of atom. For example, oxygen (O₂) and gold (Au) are elements.Compounds are pure substances formed when two or more types of atoms bond together chemically, such as water (H₂O) and carbon dioxide (CO₂).In summary, matter can be classified into two broad categories: pure substances and mixtures. Pure substances include elements and compounds while mixtures are physical combinations of pure substances.
What best describes the battery in this picture? an electrolytic cell that has spontaneous half reactions
multiple voltaic cells that have spontaneous half reactions
an electrolytic cell that has nonspontaneous half reactions
multiple voltaic cells that have nonspontaneous half reactions
Answer:
multiple voltaic cells that have spontaneous half reactions
Explanation:
A battery is an electrochemical device that stores energy. This is connected to an electrical circuit, and chemical energy is transformed into electrical energy. All are similar in construction, each of these cells is composed of a positive and a negative electrode in addition to a separator. When the battery is discharged, an electrochemical change occurs between the different materials in the two electrodes. The electrons are transported between the positive and negative electrodes through an external circuit (light bulbs, starter motors, etc.)
Answer:
i listened to that person ^^^
Explanation:
Edge doesnt give correct answers on unit tests, but i passed with an 88 :)
4. If 0.130 g of p-aminophenol is allowed to react with excess acetic anhydride, what is the theoretical yield of acetaminophen in moles? In grams?
Hey There!
p-aminophenol (109.13 g/mol) + Ac2O (102.09 g/mol) ---> acetominophen (151.16 g/mol)
next, since you already know your limiting reactant (p-aminophenol), convert it to mols :
0.130 g / (109.13 g/mol) = 0.00119 moles
now that's your theoretical max, since its a 1:1 mol ratio, so multiply by the new molecular weight. :
0.00119 * 151.16 = 0.180 g
Hope that helps!
The theoretical yield of acetaminophen is equal to 1.19 × 10⁻³ mol.
What is a theoretical yield?The amount of a product obtained from a chemical reaction is expressed as the yield of the reaction. The amount of product predicted by stoichiometry is known as the theoretical yield, whereas the actual quantity obtained is called the actual yield.
Given the mass of the p-aminophenol = 0.130 g
The reaction between the p-aminophenol and acetic anhydride gives acetaminophen and acetic acid. As given the acetic anhydride is in excess, therefore, p-aminophenol will decide the amount of acetaminophen.
The molar mass of p-aminophenol = 109.13 g/mol
The number of moles of p-aminophenol = 0.130/109.13 = 1.19 × 10⁻³ mol
Therefore, 1.19 × 10⁻³ mol of acetaminophen will be formed.
The molar mass of the acetaminophen = 151.16 g/mol
The mass of the acetaminophen = 1.19 × 10⁻³ × 151.16 = 0.18 g
Therefore, the theoretical yield of acetaminophen is 1.19 × 10⁻³ moles.
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Is 2h2 + o2 2h2o a balanced chemical equation?is it obeying the law of conservation of matter
Yes, this is a balanced chemical equation, and it obeys the Law of Conservation of Mass.
A balanced chemical equation obeys the Law of Conservation of Mass if there are the same numbers of each type of atom on each side of the reaction arrow.
2H₂ + O₂ ⟶ 2H₂O
Let’s check the numbers.
Atom On the left On the right
H 4 4
O 2 2
We have the same numbers of H and O atoms on each side of the reaction arrow.
The equation is balanced and it obeys the Law of Conservation of Mass.
Please Please help me, I don't know if this is the right subject But plz!!!!!!!!!!
A consumer is an animal that eats other animals. For example, a snake is a consumer.
Write the electron configuration for a chlorine atom. Calculate the total number of electrons in each energy level and state which energy levels are not full.
I know that the electron configuration for a chlorine atom is [Ne] 3s2 3p5 but I need help figuring out the total number of electrons in each energy level and state. Thanks :)
Answer:
First , second energy levels are complete where as third energy level is not.
Explanation:
Electronic configuration is defined as distribution of electrons of an element in its various energy levels.
Chlorine has an atomic number of 17. Which means that its has 17 proton and 17 electrons.
Electronic configuration of chlorine is given as:
[tex]Cl=1s^22s^2p^63s^23p^5[/tex]
Energy level which fully filled are : 1s , 2s , 2p
Energy level which are not fully filled are : 3s, 3p
First , second energy levels are complete where as third energy level is not.
The chlorine atom has 2 electrons in the 1st energy level, 8 in the 2nd, and 7 in the 3rd. The first two energy levels are full while the 3rd energy level is not full as it could accommodate one more electron.
Explanation:The electron configuration for a chlorine atom is [Ne] 3s2 3p5. This stands for 1s2 2s2 2p6 3s2 3p5 considering the entire configuration. To calculate the total number of electrons in each energy level, we first need to understand that the number in front of the 's' or 'p' (also 'd' or 'f' in larger atoms) represents the principal quantum number, also known the energy level of the electrons.
So, the total number of electrons for each energy level is as follows:
1st energy level (1s): 2 electrons2nd energy level (2s and 2p): 2 + 6 = 8 electrons3rd energy level (3s and 3p): 2 + 5 = 7 electronsNow, as we know that the 1st energy level (s-orbital) can hold up to 2 electrons, 2nd level (s and p orbitals) can hold up to 8 electrons, and the 3rd one can hold up to 18 (but due to it being a p-element, chlorine will only use up to 8), we conclude that the 3rd energy level is not full because it has 7 electrons while it could hold at least one more.
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Can someone help me with this it’s due tomorrow can someone plz help me
It’s about science but I’m not sure wh
what year did mendeleev organized his periodic table in order of increasing atomic number
Mendeleev organized his periodic table in order of increasing atomic number in 1869.
Dmitri Mendeleev a Russian chemist organized his periodic table in 1869 by increasing atomic mass not atomic number. The organization by increasing atomic number occurred in the 20th century.
Explanation:The Russian chemist Dmitri Mendeleev first organized the periodic table in 1869. However, it's important to note that Mendeleev initially arranged the elements based on increasing atomic mass. It was not until the 20th century that the periodic table was arranged by increasing atomic number. Thus Mendeleev himself did not organize the periodic table based on atomic number this happened much later after realization that periodic properties of the elements were better correlated with atomic number rather than atomic mass.
Mendeleev also predicted the existence of elements that were not yet discovered during his time and these elements when discovered followed the properties he had anticipated. This offered great validation to his version of the periodic table.
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For which of the following processes would there be a decrease in entropy?
A. Melting ice
B. Separation of a compound
C. Boiling water
D. Freezing water
d. Freezing water!
hope this helps! :3
Final answer:
Correct answer - D, Freezing water. The process with a decrease in entropy is freezing water, as the water molecules become more structured. The freezing process is exothermic, while boiling water is endothermic. The concept of entropy fits within the larger framework of the second law of thermodynamics involving energy transfers.
Explanation:
The process in which there would be a decrease in entropy is D freezing water. Entropy is often associated with randomness or disorder within a system. When water freezes, its molecules become more ordered and structured, which is a transition from a state of higher entropy (liquid water) to a state of lower entropy (ice).
To label the processes as endothermic or exothermic:
a. Water boiling - Endothermic
b. Gasoline burning - Exothermic
c. Ice forming on a pond - Exothermic
The decrease in entropy when water freezes does not violate the second law of thermodynamics because the entropy of the surroundings increases, typically via the release of heat. In thermodynamics, when energy is transferred as heat from one system, the system losing heat decreases in entropy, but the surroundings increase in entropy.