Poor electrical conductors like glass, plastic, wood, etc. conduct heat mainly through vibrations among the molecules. As molecules vibrate, they bump into their neighbors from time to time, transferring some of their energy (i.e. heat). Those neighbors then bump in to some of their neighbors on the other side and transfer some of the energy to them. The process continues, and the heat is transferred through the material, but it happens quite slowly because the molecules are mostly stuck in place (because they're part of a solid material. If they were liquid or gas, they could move around more freely and transport heat more quickly. That process is called convection, rather than conduction). Anyway, metals and other good electrical conductors have the ability to transfer energy through an additional mechanism. In this case, the vibrating molecules literally shake off some of their weakly-bound electrons (which are plentiful in metals and all other good electrical conductors). These high-energy electrons then fly away and bump into other molecules or electrons, transferring the heat. Unlike entire vibrating molecules, however, individual electrons are so small that they can travel much longer distances at much, much higher speeds before they bump into anything. (It's sort of like shooting a gun in a forest. The bullet may travel several hundred feet or more before it actually strikes a tree. If you tried to drive a bus in that same forest, however, you couldn't go more than a few feet without running into something) Hope this helps :)
Metals are good conductors of both electricity and heat due to the presence of free electrons that facilitate energy transfer, resulting in high thermal conductivity. Nonmetals are generally poor heat conductors and are considered insulators because they lack these free electrons, which causes them to transfer heat much slower.
The ability to conduct heat distinguishes metals from nonmetals. Metals like copper, aluminum, and silver are good conductors of electricity and, correspondingly, are also good thermal conductors. The thermal conductivity of metals can largely be attributed to the presence of free electrons that facilitate the transfer of energy as heat.
Nonmetals, on the other hand, typically have a lower thermal conductivity and are considered insulators. Materials such as wood, plastic, and rubber have a limited ability to conduct heat, causing them to be inefficient at transferring thermal energy compared to metals.
The difference is so notable that touching a metal object and a nonmetal object at the same temperature often results in the metal feeling colder due to its rapid heat conduction away from the hand. This property of metals is because they allow energy to flow more quickly throughout the material, whereas nonmetals like paper and Styrofoam conduct energy so slowly that they appear to maintain warmth for longer periods.
If Spongebob is under water than what is the substance beneath the water that they swim in
Answer:
The seafloor
Explanation:
the bottom of the ocean, aka the sea floor.
usually made from sand
Answer:
H2O
Explanation:
The equation for density is mass divided by volume. An increase in density can result from all of the following except...
What are the options? An increase in density does not occur in an increase of volume or a decrease of mass.
What happens to particles in a solid when heat is applied?
Answer: The particles move faster and spread further apart
Explanation:
What mass of carbon dioxide is produced from the complete combustion of 6.40*10^-3 g of methane
Answer:- [tex]1.76*10^-^2[/tex] g of carbon dioxide.
Solution:- The balanced equation for the combustion of methane is:
[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]
There is 1:1 mol ratio between methane and carbon dioxide. Grams of methane are converted to moles and then using mol ratio we get the moles of carbon dioxide that could further be converted to grams. The calculations are shown as:
[tex]6.40*10^-^3gCH_4(\frac{1molCH_4}{16gCH_4})(\frac{1molCO_2}{1molCH_4})(\frac{44gCO_2}{1molCO_2})[/tex]
= [tex]1.76*10^-^2gCO_2[/tex]
So, complete combustion of given amount of methane gives [tex]1.76*10^-^2gCO_2[/tex] .
How many termination code words are there?
There're three termination codons
IN RNA IN DNA NAME
UAG TAG "amber"
UAA TAA "ochre"
UGA TGA "opal"
Answer:
There are three termination code words.
Explanation:
From the question stated, we have three termination code words as shown below.
IN RNA IN DNA NAME
UAG TAG "amber"
UAA TAA "ochre"
UGA TGA "opal"
A student designs an experiment where she will add varying amounts of sugar to a chemical reaction and then measure the mass of the chemicals produced during each reaction. The independent variable in this experiment is:
A) The amount of sugar
B) The mass of the chemical produced
C) The temperature of the reaction
D) The type of chemical reaction
A. The amount of sugar
Answer: A) The amount of sugar
Explanation:
The independent variable is the one which can be changed, altered or even manipulated manually so as to bring changes and alteration over the dependent variable. The dependent variable is the variable in which changes occur due to independent variable. It is the outcome of the experiment.
The amount of sugar is the correct option. This is because of the fact that amount of sugar can bring a change over the chemical reaction and mass of chemicals being produced.
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.
https://brainly.com/question/1596638
Answer:
1st is Nucleus and 2nd is Orbitals
Explanation:
in this equation 2mg+o2=2mgo what is the coefficient to the oxygen molecule
A,2
B,4
C,1
D,0
Hello!
In this chemical equation, there are two main elements. Those elements are magnesium (Mg) and oxygen (O).
Molecules are a group of atoms bonded together, and in this case, the oxygen molecules is O2, but not 2MgO because there are two different molecules in this compound.
Coefficients are a number that multiply an entire molecule, and are also placed in front of it. In this case, O2 has no coefficient, but a subscript of 2. But, every molecule in this equation must have a coefficient and if add a coefficient of 1 to the oxygen molecule, it does nothing to the overall balancing of equations.
Therefore, the coefficient to the oxygen molecule is choice C, 1.
We have that It is seen from the equation that the Number or variable that Precedes the Oxygen atom is 1
Option C
From the question we are told
in this equation 2mg+o2=2mgo what is the coefficient to the oxygen molecule
A,2
B,4
C,1
D,0
Generally
Coefficient of a molecule is the digit, Number or variable that precedes the Molecule
Therefore
It is seen from the equation that the Number or variable that Precedes the Oxygen atom is 1
Option C
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If pecans sale for three dollars per pound and there are 127 pecans per pound how many pecans can you buy for $14.12
With $14.12, and a price of $3 per pound, you can buy 4 pounds of pecans, which equates to 508 pecans, since each pound has 127 pecans.
Explanation:To determine how many pecans can be bought for $14.12, we need to calculate the number of pounds that can be purchased and then multiply by the number of pecans per pound. The given price is $3 per pound, and there are 127 pecans per pound.
First, divide the total amount of money by the price per pound:
$14.12 ÷ $3.00 = 4.7067 pounds
Since you cannot purchase a fraction of a pecan, we need to find the maximum whole number of pounds that can be bought with $14.12, which is 4 pounds. Multiplying this number by the number of pecans per pound gives the total number of pecans that can be bought:
4 pounds × 127 pecans/pound = 508 pecans
Therefore, you can buy 508 pecans for $14.12.
Which statements describe the six elements found in all living things? Check all that apply.
Carbon is the basis of all living things.
Sulfur is found in bones, where it provides strength.
Nitrogen is found in certain foods.
Oxygen and hydrogen combine with each other to form water.
Only carbon, hydrogen, and phosphorus are found in organic compounds.
Carbon, oxygen, hydrogen, nitrogen, phosphorus, and sulfur are found in organic compounds.
Answer:
Carbon is the basis of all living things
Nitrogen is found in certain foods
Oxygen and hydrogen combine with each other to form water
Carbon, oxygen, hydrogen, nitrogen, phosphorus and sulfur are found in organic compounds
Explanation:
We are all made up of mainly three elements, Carbon, Hydrogen, and Oxygen. These three elements are found in every living organism on our planet, and along with a few trace elements, they make up all the nutrients we take in and use to build our bodies and survive.
Nitrogen is primarily found in meats, and this is because nitrogen is a key element in amino acids (which are used to build proteins), however we cannot directly assimilate nitrogen from the air, so we have to assimilate it through amino acids already synthesized in plants, or in proteins found in meat.
The chemical formula for water is H₂O. Seeing the chemical formula, it is obvious that hydrogen and oxygen are the only elements in the water molecule.
In our bodies, we use phosphorus to form our skeleton and help maintain it, sulfur and nitrogen can be found in some amino acids, and carbon, hydrogen and oxygen can be found in carbohydrates, lipids and proteins.
Answer:
Carbon is the basis of all living things
Nitrogen is found in certain foods
Oxygen and hydrogen combine with each other to form water
Carbon, oxygen, hydrogen, nitrogen, phosphorus and sulfur are found in organic compounds
Explanation:
LOL FREE POINTS
List the number of protons, neutrons, and electrons in... ( there is a pic)
Carbon:
Protons: 6
Neutrons: 7
Electrons: 6 (in a neutral atom)
Hope that helps:)
A thermometer shows that the temperature of the air in a room has increased.Which type of energy has increased?
Kinetic energy has increased.
The Kinetic Molecular Theory of gases states that the average kinetic energy of the molecules of a gas is directly proportional to its Kelvin temperature.
Thus, if the temperature of the air in a room has increased, the average kinetic energy of its molecules has increased.
Descending into Earth’s interior, temperature, as well as pressure on rock, _____.
1 remains fairly constant
2 increases
3 varies seasonally
4 decreases
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.
Identify the type of reaction represented by each equation.
A: H2 + Cl2 → 2HCl
B: CH4 + 2O2 → CO2 + 2H2O
Equation A represents a _________ reaction, and equation B represents a_______ reaction.
choices for both blanks
combustion
decombustion
synthesis
double displacement
single displacement
choose one for each blank
there are some notes and examples in the images
my opinions are
1.blank---snythesis
2blank--combustion
please tell me if im correct
16pionts
Answer : Equation A represents a synthesis reaction, and equation B represents a combustion reaction.
Explanation :
A : [tex]H_2+Cl_2\rightarrow 2HCl[/tex]
Equation A is a synthesis reaction in which the two reactants combine to form a single product.
B : [tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]
Equation B is a combustion reaction in which the a hydrocarbon react with an oxygen to give carbon dioxide and water a s a product.
Hence, the equation A represents a synthesis reaction, and equation B represents a combustion reaction.
From the illustration, the type of reaction represented by equation A would be a synthesis reaction while that of B would be a combustion reaction.
In synthesis reactions, two or more atoms of different elements or molecules come together to form a product. In equation A, H2 and Cl2 come together to form HCl. Thus, A is a synthesis reaction.
In combustion reactions, substances react in oxygen to generate new products, usually accompanied by light and the generation of heat. In equation B, CH4 reacts with O2 to produce CO2 and H2O with the production of heat. Thus, B is a combustion reaction.
More on different types of reactions can be found here: https://brainly.com/question/20479735
Which of the following is the electron configuration of an electrically neutral atom of argon (Ar)?
(a) 1s² 2s² 2p5
(b) 1s² 3d¹⁰ 4f⁷
(c) 1s² 2s² 2p⁶ 3s² 3s⁶
(d) 1s² 2s1
You run a “5k” for charity. How many feet do you run
It would roughly be 16,404 feet. Or if you wanted to be more specific 16,404.2. I hope this helps.
Easiest way is dimensional analysis.
[tex]5km * \frac{3280.84ft}{1km} = 16404.2[/tex]
a graduated cylinder weighed 83.2 g and 57.0 mL of water was added to the graduated. How much does it weigh now?
The new weight of the graduated cylinder after adding 57.0 mL of water is 140.2 g.
To determine the new weight of a graduated cylinder after adding water, we need to consider the mass of the water added. The step by step solution is as follows:
First, we know the mass of the empty graduated cylinder is 83.2 g.We added 57.0 mL of water to the cylinder.Since the density of water is 1.0 g/mL, the mass of the water is equivalent to its volume. Therefore, the mass of the 57.0 mL of water is 57.0 g.Now, add the mass of the water to the mass of the empty graduated cylinder to get the total mass:Total Mass = 83.2 g (graduated cylinder) + 57.0 g (water) = 140.2 g
Thus, the graduated cylinder now weighs 140.2 g.
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
You have 47.0 mL of a 0.400 M stock solution that must be diluted to 0.100 M. Assuming the volumes are additive, how much water should you add?
Hey there!
Moles of stock solution:
47.0 mL in liters : 47.0 / 1000 => 0.047 L
n = M * V
n = 0.400 * 0.047
n = 0.0188 moles
Volume final :
M = n / V
0.100 = 0.0188 / V
V = 0.0188 / 0.100
V = 0.188 L => 188 mL
Therefore Watter added :
volume final - volume initial
188 mL - 47.0 mL => 141 mL
Hope That helps!
Writing net ionic equation.
Sn(No3)2(aq)+K2S(aq) -> SnS(s)+2KNO3(aq)
Hey There!
Expand soluble ions to get complete ionic equation:
Sn²⁺(aq) + 2 NO³⁻(aq) + 2 K⁺(aq) + S²⁻(aq) :
SnS(s) + 2 K⁺(aq) + 2 NO³⁻(aq)
Cancel common ions to get net ionic equation:
Sn²⁺(aq) + S²⁻(aq) => SnS(s)
Hope that helps!
To obtain the whole ionic equation, expand the soluble ions:
What is meant by soluble ions ?Water molecules surround and solvate the ions, weakening the strong electrostatic interactions between them, which causes the ions to separate and spread equally throughout the solution when ionic compounds dissolve in it.
Equations become :
Sn²⁺(aq) + 2 NO³⁻(aq) + 2 K⁺(aq) + S²⁻(aq) :
SnS(s) + 2 K⁺(aq) + 2 NO³⁻(aq)
To obtain the net ionic equation, eliminate common ions:
Sn²⁺(aq) + S²⁻(aq) => SnS(s)
To learn more about Soluble ions, refer to the below link:
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Will give brainliest!! Explain how extinct organisms have left their evidence behind, which scientists now study.
theyre fossils, when extinct beings such as dinosaurs died their bones would sometimes get stuck in clay or amber (i cant remember if theres any other types of rock) or sediment) and stay there for years and years then scientist called Paleontologists find them and study them. hope this helps:)
Answer:
What is meant by extinct How do scientists obtain information about extinct species?
How do scientists obtain information about extinct species? A species is extinct if no members of that species are still alive. Most of what scientists know about extinct species is based on the fossil record. What are mass extinctions?
Explanation:
Which is not an example of symbiosis
Answer:
lepords
Explanation:
The correct answer is: An example of an organism that is not an example of symbiosis would be a predator-prey relationship where the interaction is not obligatory for either species' survival.
Symbiosis is a close and long-term interaction between two different biological organisms. There are three main types of symbiosis: mutualism, commensalism, and parasitism. In mutualism, both species benefit from the interaction. In commensalism, one species benefits while the other is neither harmed nor benefited. In parasitism, one species, the parasite, benefits at the expense of the other, the host.
A predator-prey relationship, such as a lion hunting a zebra, is typically not considered symbiosis because it is usually a short-term interaction and not obligatory for the survival of either species. While both species are involved in an ecological interaction, the relationship is not symbiotic in the sense that it does not meet the criteria of being a close, long-term interaction that is essential to the survival of either species. Each species can potentially find other sources of food, and the interaction does not necessarily occur over a significant portion of the organisms' life spans.
In contrast, examples of symbiosis include:
- The relationship between clownfish and sea anemones, which is a case of mutualism where the clownfish gains protection from predators among the anemone's tentacles, and the anemone benefits from the clownfish's waste as nutrients and the clownfish's defense against anemone predators.
- The relationship between barnacles attached to whales, which is commensalism, as the barnacles get transportation and access to food without significantly harming or benefiting the whale.
- The relationship between tapeworms and their hosts, which is parasitism, as the tapeworm lives in the host's intestine and absorbs nutrients from the host's diet, causing harm to the host.
Therefore, a predator-prey relationship like that of a lion and a zebra is not an example of symbiosis because it lacks the necessary characteristics of a close, long-term, and obligatory interaction for the survival of the involved species."
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.
All moving objects have momentum.
true or false ?
Final answer:
The statement that all moving objects have momentum is true because momentum is a product of an object's mass and velocity, both of which are non-zero for moving objects.
Explanation:
The statement that all moving objects have momentum is true. Momentum is the product of an object's mass and velocity and is given by the equation p = mv, where p is momentum, m is mass, and v is velocity. Since any object that is moving has a velocity greater than zero and a non-zero mass, it will indeed have momentum. Additionally, momentum is a vector quantity, which means it has both magnitude and direction, and it is measured in kilograms meters per second (kg·m/s).
To further elucidate, let's consider the Law of Conservation of Momentum, which states that in a closed system, the total momentum remains constant unless acted upon by an external force. Therefore, if two objects collide and come to rest, as mentioned in the problem, the momentum is not lost but transferred, ensuring the total momentum before and after the collision is the same.
Is N2 + 3H2 →2NH3 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.
N₂ + 3H₂ ⟶ 2NH₃
Let’s check the numbers.
Atom On the left On the right
N 2 2
H 6 6
We have the same numbers of H and O on each side of the reaction arrow.
The equation is balanced and it obeys the Law of Conservation
of Mass.
Which of the following states an important result of Rutherford's gold-foil experiment?
A. Atoms have mass.
B. Electrons have a negative charge
C. Neutrons are uncharged particles
D. The atom is mostly empty space
Rutherford's gold-foil experiment showed that D. the atom is mostly empty space.
When he shot α particles at a thin gold foil, most of them went straight through the foil without being deflected.
However, a few of the α particles were deflected by rather large angles. He concluded that the atom is mostly empty space with almost all its mass concentrated in a small central nucleus.
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 is the hydroxide ion concentration of an unknown acid with a ph of 1.9?
Hey there!:
[ H⁺ ] = [tex]10^{-pH}[/tex]
[H⁺ ] = [tex]10^{-1.9}[/tex]
[ H⁺ ] = [tex]1.26*10^{-2} M[/tex]
Hope that helps!
The concentration of hydroxide ion of unknown acid is [tex]\boxed{7.9344 \times {{10}^{ - 13}}\;{\text{M}}}[/tex]
Further Explanation:
An acid is a substance that has the ability to donate [tex]{{\text{H}}^ + }[/tex] ions or can accept electrons from the electron-rich species. The general dissociation reaction of acid is as follows:
[tex]\text{HA}}\to{{\text{H}}^+}+{{\text{A}}^-}[/tex]
Here, HA is an acid.
The acidic strength of an acid can be determined by pH value. The negative logarithm of hydronium ion concentration is defined as pH of the solution. Lower the pH value of an acid, the stronger will be the acid. At [tex]25\;^\circ {\text{C}}[/tex], pH value of an acid is less than 7.
The formula to calculate pH of acid is as follows:
[tex]{\text{pH}} = -\log\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^+}}\right][/tex]
Here,
[tex]\left[ {{{\text{H}}_3}{{\text{O}}^ + }} \right][/tex] is the concentration of hydronium ion.
The relation between the concentration of hydronium ion and hydroxide ion is as follows:
[tex]\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^+}}\right]\left[{{\text{O}}{{\text{H}}^ - }}\right] = {10^{ - 14}}[/tex]
Here,
[tex]\left[ {{{\text{H}}_3}{{\text{O}}^ + }} \right][/tex] is the concentration of hydronium ion.
[tex]\left[ {{\text{O}}{{\text{H}}^ - }} \right][/tex] is the concentration of hydroxide ion.
Given information:
The pH value of unknown acid is 1.9.
To calculate:
The hydroxide ion concentration of unknown acid.
Solution:
Step 1: Initially, we have to calculate the concentration of hydronium ion by using equation (1).
The formula to calculate pH of the unknown acid is as follows:[tex]{\text{pH}} = - \log \left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right][/tex]
...... (1)
Rearrange the equation (1) to calculate the concentration of hydronium ion.
[tex]\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right] = {10^{ - {\text{pH}}}}[/tex]
...... (2)
Substitute 1.9 for pH in the equation (2).
[tex]\begin{gathered} \left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right] = {10^{ - 1.9}} \\ = 1.2589 \times {10^{ - 2}}\;{\text{M}} \\ \end{gathered}[/tex]
Step 2: The concentration of hydronium ion calculated in step (1) can be used to calculate the concentration of [tex]{\text{O}}{{\text{H}}^ - }[/tex] ions by using the relation (3).
The relation between the concentration of hydronium ion and hydroxide ion is as follows:
[tex]\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right]\left[ {{\text{O}}{{\text{H}}^ - }} \right] = {10^{ - 14}}[/tex] ...... (3)
Rearrange the equation (3) to calculate the concentration of hydroxide ion.
[tex]\left[ {{\text{O}}{{\text{H}}^ - }} \right] = \frac{{{{10}^{ - 14}}}}{{\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right]}}[/tex] ...... (4)
Substitute [tex]1.2589 \times {10^{ - 2}}[/tex] for \left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right] in the equation (4).
[tex]\begin{gathered} \left[ {{\text{O}}{{\text{H}}^ - }} \right] = \frac{{{{10}^{ - 14}}}}{{1.2589 \times {{10}^{ - 2}}}} \\ = 7.9434 \times {10^{ - 13}}\;{\text{M}} \\ \end{gathered}[/tex]
Learn more:
1. The reason for the acidity of water https://brainly.com/question/1550328
2. Reason for the acidic and basic nature of amino acid. https://brainly.com/question/5050077
Answer details:
Grade: Senior School
Subject: Chemistry
Chapter: Acids, bases, and salts
Keywords: pH, acid, pOH, base, hydronium ion, hydrogen ion, hydroxide ion, acidic nature, and basic nature.
BRAINLIEST IF CORRECT MUST USE WORK. Which option is an example of a chemical property?
A. boiling point
B. rusting ability
C. melting point
D. density
Rusting ability is a chemical property.
Since the act of rusting creates a new material (an oxide), it is a chemical change. The other three are physical properties, since they do not involve the formation of a new substance.