Arsenic, lead, mercury and chloroform are examples of hazardous substances. These are heavy metals which attach to your cells that thwart your organs from accomplishing their job.
What are the sources of lead, arsenic and mercury?Lead, mercury and arsenic are widely scattered in the environment. Grown-ups are mostly exposed to these contaminants in the workplace. Children can be exposed to poisonous metals from multiple sources, including contaminated air, soil, water and food.
Is arsenic poisonous?Arsenic is highly poisonous in its inorganic form. Contaminated water which is used for drinking, in preparation of food and irrigation of crops have the greatest threat to public health. Long-term consumption of arsenic can cause skin lesions and cancer.
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How many moles of aluminum do 4.70×1024 aluminum atoms represent?
One mole of aluminum contains 6.02 × 10²³ Al atoms or formula units. Hence, 4.70 × 10²⁴ atoms of Al contains 7.8 moles of Al.
What is one mole ?One mole of a substance is its amount containing 6.02 × 10²³ atoms or molecules. This number is called Avogadro number. One mole of every elements contains Avogadro number of atoms.
Similarly one mole of every compound contains 6.02 × 10²³ molecules. The mass of one mole of an element is called its atomic mass.
Al is 13th element in periodic table. Zn is a transition metal. One mole of Al contains 6.02 × 10²³ Al atoms . Hence number of moles of 4.70 × 10²⁴atoms is:
4.70 × 10²⁴ / 6.02 × 10²³ =7.8 moles .
Hence, there will be 7.8 moles of aluminum.
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A metal oxide with the formula MO contains 19.66% oxygen. Type the symbol for the element represented by M.
The oxygen content of something like a metal oxide matching the composition MO is 19.66%. The element M is represented by the Zn symbol.
What are metals and an example of one?The elements with boiling and melting temperatures and glossy crystalline solids are known as metals. Metals are efficient heat and electrical conductors. Metals like iron, aluminium, nickel, silver, and tin, for instance, are utilized frequently in our daily lives.
Who made the metal?Native Metals were originally discovered and used by ancient man around 5000 BC. In the following two thousand years, up until the beginning of the Bronze Age, humankind perfected the techniques for discovering, working with, and using these local metals. Gold nuggets were frequently the simplest to locate and utilize.
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please help answer that and show step by step working
The amount of electricity is required to deposit one mole of aluminium from a solution of [tex]$\mathrm{AlCl}_3$[/tex] exists Three Faradays.
What is meant by mole?The unit of measurement used by chemists known as a mole is very significant. In the same way that having a dozen eggs implies you have twelve eggs, having a mole of anything indicates you have 602,214,076,000,000,000,000,000 of that thing. When measuring very small objects like atoms, molecules, or other particles, chemists must use moles.
In the International System of Units, a substance's amount is measured in moles, which are denoted by the sign mol. The quantity of a substance is a measurement of the number of elementary entities of a specific substance present in an object or sample.
The quantity of atoms is measured in terms of moles. Mole conversion can be done for units like grams and milligrams.
[tex]$$A l^{3+}+3 e^{-} \rightarrow A l$$[/tex]
The amount of electricity required = 3 Faraday.
Therefore, the correct answer is option C. Three Faradays,
The complete questions:
What amount of electricity is required to deposit one mole of aluminium from a solution of [tex]$\mathrm{AlCl}_3$[/tex] ?
A. One Faraday
B. One ampere
C. Three Faradays
D. Three amperes
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in this exercise, you will interpret how to read a safety data sheet (sds) by listing the basic information provided on a sds. Use the Internet to find the SDS for regular bleach (sodium hypochlorite, 4-6%)
A safety data sheet is a document which contains information regarding occupational safety and health hazards pertaining to a certain chemical product.
A variety of data is listed on the safety data sheet which can be used as and when required. The data that can be read from the safety data sheet include Chemical Product and Company Identification, Composition, Information on Ingredients, Hazards Identification, First Aid Measures, Fire Fighting Measures, Accidental Release Measures, Handling and Storage, Exposure Controls, Personal Protection, Physical and Chemical Properties, Stability and Reactivity , Toxicological Information, Ecological Information, Disposal Considerations, Transport Information, Regulatory Information, etc. The more recent Safety Data Sheet format is internationally standardised, unlike the older MSDS formats, which might vary from source to source within a nation according on national restrictions.
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which of the following statements are true about cations? select all that are true. they are positively charged. they are negatively charged. they are formed by removing protons from a neutral atom. they are formed by adding protons to a neutral atom. they are formed by removing electrons from a neutral atom. they are formed by adding electrons to a neutral atom.
They are positively charged and they are formed by removing electrons from a neutral atom.
A cation may be defined as an atom or molecule that is positively charged.
By shedding its single valence electron, a neutral sodium atom is likely to acquire an octet in its outermost shell.
Na→Na++e−
To distinguish it from the element, the cation created in this manner, Na+, is known as the sodium ion. The second electron shell, which contains eight electrons, is the sodium ion's outermost shell. This satisfies the octet rule.
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Would bromoethene act as a dienophile under mild conditions?
Answer:The Diels-Alder reaction is a conjugate addition reaction of a conjugated diene to an alkene or alkyne (the dienophile) to produce a cyclohexene.
Explanation:
Bromoethene, also known as 1,2-dibromoethene or ethylene dibromide, is an unsaturated compound with a double bond between the carbon atoms. Dienophiles are molecules that can react with a diene, which is a compound with two double bonds, to form a cyclic compound through a Diels-Alder reaction.
Bromoethene is not considered a dienophile in the Diels-Alder reaction. The Diels-Alder reaction is a type of pericyclic reaction that requires a high degree of orbital symmetry between the dienophile and diene, and the double bond in bromoethene does not possess the required symmetry for this reaction. Additionally, the bromine atoms in bromoethene are electron-withdrawing and decrease the reactivity of the double bond, making it less likely to act as a dienophile.
Therefore, it is unlikely that bromoethene would act as a dienophile under mild conditions.
A student in a lab measures a current flowing three a long loop of wire if the is no battery connected to the wire witch of the follow explained the source of the current
When a current flows through a wire over an extended period of time, heating effect takes place, meaning the temperature of the wire rises, which causes the wire's resistance to rise.
What happens if a circuit's current is allowed to run continuously for a prolonged period of time? When a current flows through a wire over an extended period of time, heating effect takes place, meaning the temperature of the wire rises, which causes the wire's resistance to rise.As a result, when the current through the electric bulb is reduced, less heat and light energy are produced.So, the brightness goes down.The light bulb will light up when a capacitor is added to a circuit that also includes a battery and a light bulb because the capacitor will first charge up and the circuit will have a nonzero current flowing through it as this charging process takes place.Due to the inclusion of a second resistor to the circuit, closing the switch reduces current.To learn more about current refer
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earth is attracted to. the sun by. the. force of. gravity. why. doesn't the earth fall into. the. sun
Answer:
because of the balance in centripetal and centrifugal forces.
Answer:
The earth's momentum, its centripetal and centrifugal forces, prevent it from falling into the sun.
The chemical equation below shows the reaction between carbon dioxide (CO2) and lithium hydroxide (LiOH). CO2 + 2LiOH Right arrow. Li2CO3 + H2O The molar mass CO2 is 44.01 g/mol. How many moles of LiOH are needed to react completely with 25.5 g of CO2? 0.290 moles 0.579 moles 1.16 moles 1.73 moles
As per the given reaction, 2 moles or 46 g of LiOH is needed to completely react with CO₂. Then, 25.5 g of CO₂ requires 1.16 moles of LiOH.
What is lithium hydroxide ?Lithium hydroxide is an ionic compound formed by the combination of metallic lithium and water moiety. LiOH easily reacts with carbon dioxide forms an insoluble compound lithium carbonate and water.
As per the given balanced equation of the reaction between LiOH and carbon dioxide, one mole of CO₂ reacts with 2 moles of LiOH.
molar mass of CO₂ = 44 g/mol
molar mass of LiOH = 23 g/mol
mass of 2 LiOH = 46 g.
Then, mass of LiOH needed to react with 25 .5 g of CO₂ = (25.5 × 46) /44 = 26.13 g
Number of moles in 26.13 g of LiOH = 26.13/23 = 1.16 moles.
Therefore, the number of moles of LiOH are needed to react completely with 25.5 g of CO2 is 1.16 moles.
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for a given reaction, kc is the equilibrium constant based on the molar of reactants and products while kp is the equilibrium constant based on the partial of reactants and products.T/F
The statement is true that for a given reaction, kc is the equilibrium constant based on the molar of reactants and products while kp is the equilibrium constant based on the partial of reactants and products.
Kp And Kc are the equilibrium constant of an ideal gaseous mixture.Kp is equilibrium constant used when equilibrium concentrations are expressed in atmospheric pressure and Kc is equilibrium constant used when equilibrium concentrations are expressed in molarity. However, the difference between the two constants is that Kc is defined by molar concentrations, whereas Kp is defined by the partial pressures of the gasses inside a closed system.Relation between Kp and Kc depends on the change in the number of moles of gaseous reactants and products (△n).Go through the given link below to know more about equilibrium:-
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when a system reaches equilibrium, the transition of individual molecules from reactants to products or products to reactants stops, and all molecules remain in the respective states they were in when equilibrium was reached. True
False
The given statement, "When a system reaches equilibrium, the transition of individual molecules from reactants to products or products to reactants stops, and all molecules remain in the respective states they were in when equilibrium was reached" is true (T) because at chemical equilibrium, all molecules to remain in their respective states.
In a chemical reaction at equilibrium, the rate of the forward reaction is equal to the rate of the reverse reaction. As a result, the concentration of the reactants and products remains constant over time, meaning that the transition of individual molecules from reactants to products or vice versa stops. The state of all the molecules remains unchanged from when the system reached equilibrium, making it a state of balance between the forward and reverse reactions. The position of equilibrium can shift if the conditions of the reaction change (such as temperature, pressure or concentration), but the system will always strive to reach a new balance once again.
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what kind of bond is at the arrow in the figure?
- peptide bond - double covalent bond - ionic bond - disulfide bridge - hydrogen bond
The kind of bond at the arrow is peptide bond.
What is peptide bond?The carboxyl group of one amino acid is connected to the amino group of another amino acid by a chemical interaction known as a peptide bond. Two or more amino acids are joined together by peptide bonds to form the final molecule, known as a peptide.
A peptide bond is most likely shown by the arrow in the illustration. The amino acids in a protein or peptide chain are joined together by a sort of covalent connection known as a peptide bond, which develops between the carboxyl group of one amino acid and the amino group of another. The covalent link between the nitrogen and carbon atoms is an amide bond.
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select the mass law(s) demonstrated by the following experimental results. experiment 1: a student heats of copper and of bromine to produce of a white compound; of bromine remains. experiment 2: a second student heats of copper and of bromine to form of a white compound; of copper remains. select all that apply: Law of multiple proportions Law of definite composition Law of mass conservation
The following experimental findings illustrate the mass laws:
1. The law of definite composition states that a compound has a definite composition if the same amounts of copper and bromine are used in both tests and the same amount of the white compound is generated.
2. Law of mass conservation: In both experiments, the amount of copper and bromine utilised is equal to the amount of white compound generated plus the amount of unreacted copper or bromine. This is known as the law of mass conservation. This demonstrates the law of mass conservation since it demonstrates that the mass of the reactants and products are equal.
3. Law of multiple proportions is not demonstrated in these experiments as only one compound is formed and the same proportion of elements is used in both experiments.
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The table shows examples of two different types of rocks. Which of these bedt compares the way that these rocks are formed?
1. Granite is formed from cooled molten rock, while gneiss is formed solid rock.
2. Granite is formed from layers of compacted material, while gneiss is formed from cooled molten rock.
Granite is formed from cooled molten rock, while gneiss is formed solid rock bedt compares the way that these rocks are formed.
What is molten rocks?
Molten rocks, also known as magma, is hot, liquid rock that is found beneath the Earth's surface. It is formed when heat and pressure cause rocks to melt, releasing gas and other materials. Molten rocks can contain crystals, gas bubbles, and other materials. When molten rock reaches the Earth's surface, it is called lava. Molten rocks can be made of many different minerals, including basalt, andesite, and rhyolite.
Therefore, Granite is formed from cooled molten rock, while gneiss is formed solid rock bedt compares the way that these rocks are formed.
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under which of the following conditions of temperature and pressure will h2 gas be expected to behave most like an ideal gas? responses 50 k and 0.10 atm 50 k and 0.10 atm 50 k and 5.0 atm 50 k and 5.0 atm 500 k and 0.10 atm 500 k and 0.10 atm 500 k and 50 atm
H₂ gas expected to behave most like an ideal gas in condition of temperature 500 K and pressure 0.1 atm.
When temperatures and pressures are extremely high and low, real gases will behave like ideal gases. Nevertheless, actual gases are less likely to behave optimally at lower temperatures and pressures.
PV=nRT is the ideal gas equation, where P is the gas pressure.
V = Gas Volume
Gas constant: R
T = gas temperature
n = the quantity of gas moles.
When the amount of gas molecules and the intermolecular interactions between them are minimal, the ideal gas functions properly. Low pressure and high temperature make this possible.
Hydrogen gas will therefore most likely possess/behave like an ideal gas at 500 K and 0.10 atm.
Consequently, we can say that the conditions under which a sample of neon gas behaves most like an ideal gas ; 500K and 0.1 atm
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1.4 copy the structure of the product of the intramolecular below. identify and label possible electrophiles. which of these electrophiles will react faster with a nucleophile? why?
In determining the reactivity of an electrophile in a nucleophilic substitution reaction, steric hindrance plays an important factor.
According to the concept of electrophilicity, an electron-deficient atom(electrophile) is attacked by electron-rich species (nucleophile).
The extent of steric hindrance determines the rate of a reaction.
SN2 reactions occur in primary, secondary and methyl carbon electrophiles. Out of these, the unhindered methyl carbon electrophiles will react the fastest, and more hindered secondary carbon electrophiles will react the slowest. Assuming that, all the other reaction conditions used are identical in nature. SN2 reactions generally do not occur in tertiary carbon electrophiles.
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Which of the following chemicals can be made of amino acids, is stored in glands, and is secreted into the bloodstream to regulate body functions?
buffer
enzyme
antibody
hormone
Answer: Hormone
Explanation: Hormones are proteins hence being made from amino acids. They are stored in glands and regulates body functions. For example when you meet something you're scared of or something dangerous, your adrenal gland will secrete adrenaline which increases your heart rate putting you in a fight or flight situation.
Which statements are true regarding acids and bases?
- Aqueous ammonia does not produce toxic vapors but ammonium hydroxide does.
- All concentrated acids require a special hood to deal with the vapors.
- Hydrogen fluoride is the safest of all the hydrogen halides.
- Nitric acid causes yellowing of the skin by denaturing proteins.
- When preparing aqueous solutions of acid, it is important to add the acid to the water to dissipate heat.
- strong acids and bases, and some weak, cause irreversible damage to living tissue
-Preparing solutions of bases can cause the water to boil.
The statements that are true regarding acids and bases are: Aqueous ammonia does not produce toxic vapors but ammonium hydroxide does. Hydrogen fluoride is the safest of all the hydrogen.
halides. Nitric acid causes yellowing of the skin by denaturing proteins. When preparing aqueous solutions of acid, it is important to add the acid to the water to dissipate heat. strong acids and bases, and some weak, cause irreversible damage to living tissue It is not always true that all concentrated acids require a special hood to deal with the vapors, it depends on the acid in question and the concentration. The statements that are true regarding acids and bases are: Aqueous ammonia does not produce toxic vapors but ammonium hydroxide does. Hydrogen fluoride is the safest of all the hydrogen. Preparing solutions of bases can cause the water to boil but also depends on the base and the concentration.
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8.02 x 10^20 atoms of copper to grams
Answer:
Explanation:
1
atom of
Cu
has a mass of
1.055
×
10
−
22
g
.
Explanation:
1 atom Cu
⋅
1 mol Cu
6.022
×
10
23
atoms Cu
⋅
63.546 g Cu
1 mol Cu
=
1.055
×
10
−
22
g Cu
1 atom of copper must be converted in moles to express it as a quantity that can be converted into grams (our second step).
Avogadro's Number
(
1 mole
=
6.022
×
10
23
particles
)
and the relative atomic mass of copper
(
1 mole of copper = 63.546 g
)
are the equalities required to make
At a resting pulse rate of 77 beats per minute, the human heart typically pumps about 67 mL of blood per beat. Blood has a
density of 1060 kg/m^3?. Circulating all of the blood in the body through the heart takes about I min for a person at rest.
1. Approximately how much blood is in the body? Volume of blood in body: m^3
2. On average, what mass of blood does the heart pump with each heart beat?
Mass per heart beat: kg
1. 5005 ml blood is in the body. 2. On average, 68.9gram of blood does the heart pump with each heart beat.
What is density ?The term density is defined as the ratio of mass and volume. It is represented by the formula density = mass / volume.
Given :
1. Density of blood = 1060 kg/m^3
At a resting pulse rate of 77 beats per minute, the human heart typically pumps about 65 mL of blood per beat. Circulating all the blood in the body through the heart takes about 1 min for a person at rest
Since we are given that heart beats per minute = 77
And Heart pumps about 65 mL of blood per beat
Therefore, blood in the body is 77 × 65 = 5005 ml
2. mass = volume × density
Then, mass of blood does the heart pump with each heart beat
= volume × density
mass = 65ml × 1060 kg/m^3
mass = 68.9gram
Thus, 1. 5005 ml blood is in the body. 2. On average, 68.9gram of blood does the heart pump with each heart beat.
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the second (si unit of time) is defined as the duration of 9192631770 cycles of the radiation corresponding to the transition between levels of the fundamental state of the cesium-133 atom.
a. true
b. false
A second is defined as the time taken by 9192631770 radiation cycles to shift the cesium-133 atom's fundamental state from one level to another (si unit of time).
Simply expressed, the study of the chemical compound that radiation, typically ionizing radiation, induces in matter is known as radiation chemistry. Common themes in the field include radiation-induced particle nucleation and growth, radiation-enhanced H 2 generation, A second is defined as the time taken by 9192631770 radiation cycles to shift the cesium-133 atom's fundamental state. And damaging effects on nuclear system chemistry. Due to its ground state electron state's [Xe] 6s1 configuration, the caesium atom's atomic term symbol is 2 S 1/2. This shows that the atom has a single unpaired electron and an overall electron spin of 1/2.
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neutral compounds of boron may be described as electron deficient based on its electron configuration predict how many covalent bonds boron will form is this the maximum number of bonds boron will form
Many covalent bonds boron will form is this the maximum number of bonds boron will form we can expect boron to form three bonds since it has three valence electrons.
Since it takes one electron from each atom to form a single bond, we can expect boron to form three bonds since it has three valence electrons. We can see this in the molecule borane BH3. Here, boron forms three covalent bonds, using all three of its valence electrons in single bonds to the hydrogens.the second electron shell has a maximum occupancy of eight electrons. This means that there’s a space for two more electrons in the second electron shell. Since boron only has three valence electrons, it can only form three covalent bonds maximum.
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. Scientists have developed a theory of how the universe formed. A. What is the name of this theory? (2 points) B. What happened according to this theory? (2 points) C. What is one form of evidence used to support this theory
Scientists have developed a theory of how the universe formed called the big bang (question a), which suggests the universe is expanding (question 2) and it is based on the relative temperature/light of far way celestial bodies (question 3).
What is the big bang theory?The big bang theory is a theory used to explain the origin of the universe, which is based on data from nature and astronomical observations.
Therefore, with this data, we can see that the big bang theory is based on experimental and observational data and suggest the universe is continuously expanding.
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write (2y)^4 without parentheses
Answer:
16y^4
Explanation:
(2y)^4 can be written as 2^4 * y^4, which simplifies to 16y^4.
A mass on a spring vibrates horizontally on a smooth level surface( see the figure). Its equation of motion is x(t)=8 sin t, where t is in seconds and x in centimeters.
a, Find the velocity and acceleration at time t.
b, Find the position, velocity, acceleration of the mass at the time t=2p/3. In what direction is it moving at that time? It is speeding up or slowing downs
a) The velocity x(t) = 8sint
The position x'(t) = 8cost
The acceleration x"(t) = -8sint
b) position, x(t) = 4√3 cm.
velocity, x'(t) = 4 cm/s
acceleration, x"(t) = -4cm/s²
a) The velocity, position and acceleration at the time t is as follows :
The velocity x(t) = 8sint
The position x'(t) = 8cost
The acceleration x"(t) = -8sint
b) The position, velocity and the acceleration of the mass at the time t = 2π / 3.
The position, x(t)=8sin(2π /3)
= 4√3 cm.
The velocity, x'(t) = 8cos(2π /3)
= 4 cm/s
The acceleration, x"(t) = 8sin(2π/3)
= -4cm/s²
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reaction of non metal with oxygen with equation
Non metals react with oxygen to form non-metallic oxides. For example, SO2 , NO2 , etc. These are usually acidic in nature. This is the reason for acid rain.
Examples:
C ( s ) + O 2 ( g ) → CO 2 ( g )
H 2 ( g ) + O 2 ( g ) → 2 H 2 O ( l )
S + O2→ SO2
Answer:
A non-metal oxide is produced when a non-metal burns in oxygen.
Explanation:
The word equation for the overall reaction is as follows:
Oxygen with non-metal result in non-metal oxide.
Non-metal + oxygen → Non-metal oxide
the mechanism through which local anesthetics reduce pain is selective blockade of blank .multiple choice question.chloride, cl-, ionsfluoride, f-, channelspotassium, or k , ionssodium, or na , channels
The mechanism through which local anesthetics reduce pain is selective blockade of Sodium, or Na+, channels.
The subunit of voltage-gated Na+ channels is targeted by local anesthetics, which blocks the channels and stops nerve impulses from being generated or transmitted. As a result, the incoming pulse of depolarization along the nerve is stopped dead in its tracks because Na+ ions cannot enter the cell. proportion of ionized local anesthetic molecules. In a split second, ionization to unionization occurs in molecules of local anesthetic. It has been shown in several clinical investigations that the addition of sodium bicarbonate to a clinical nerve block can have a variable effect, however this does not always translate to a quicker start of anesthesia.
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Raj is using rubbing alcohol to clean his typewriter. What is he MOST likely using it for?
Answer:
Dust And Grime
Explanation:
Guessing you do 7th grade k12 to
el 188497 percent of the world's water supply is difficult, if not impossible, to obtain or to use because it is in the oceans or in the form of glaciers and ice caps. Scientists are exploring methods of conserving and protecting the rest of Earth's water supply for the growing population. According to the information provided, which of the following activities most directly affects the water supply?
Producing energy and manfacturing of the following activities most Mass directly affect the water supply
what is The definition of MassAn object's mass is determined by how much matter it has. Anything that has more substance will weigh heavier overall. For instance, because an elephant contains more stuff than a mouse does, it has a heavier mass. How much energy an object contains is not determined by its size.
What does "has mass" mean?The resistance of the body to acceleration (change in velocity) when ever a net force is employed can be measured experimentally as mass, which is equivalent to inertia. The gravitational pull of an object to other bodies is also dependent on its mass.
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List the following in increasing size order (list smallest first with < between each atom) PI, X, Ar, Sr