A student in a lab holds an iron nail over an open flame, and no reaction occurs. The nail is then filed, creating small pieces of
iron shavings. These pieces burn brightly when placed over an open flame.
Which statement accurately identifies one of the changes that occurs as a physical or chemical change?

Answers

Answer 1

Formation of small pieces of iron shavings is a physical change whereas burning of pieces of iron shavings is chemical change.

Formation of small pieces of iron shavings is an example of physical change because it can be changed again into nail while on the other hand, burning of pieces of iron shavings on the flame is an example of chemical change because it can't change again into its original shape. Physical change is a change in matter which does not change the chemical properties of the matter whereas chemical change is a change in matter which change the chemical properties of the matter.

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Related Questions

Match the vocabulary words with their definitions.

1. an instrument to measure magnetism
megawatt
2. a system for the production of controlled nuclear energy
reactor
3. a million watts; thousand kilowatts
infrared
4. invisible radiation with waves longer than red
magnetometer
5. an engine in which a wheel turns by the force of wind, water, or steam
turbine

Answers

Answer:

1. magnetometer, 2. reactor, 3. megawatt, 4. infrared, 5. turbine.

Explanation:

A magnetometer is an electronic instrument used to measure magnetic fields.

(1. an instrument to measure magnetism - magnetometer)

A reactor is a device used for the production of controlled nuclear energy, there are two principles in which nuclear reactors can be based: (i) Fission, (ii) Fusion.

(2. a system for the production of controlled nuclear energy - reactor)

A million watts equals a megawatt, a power SI unit.

(3. a million watts; thousand kilowatts - megawatt)

Infrared radiation corresponds to electromagnetic waves whose wavelength is between 0.7 to 1000 micrometers.

(4. invisible radiation with waves longer than red - infrared)

A turbine is mechanical device which generates mechanical work at the expense of fluid energy.

(5. An engine in which a wheel turns by the force of wind, water or steam - turbine)

plz answer (d) explain

Answers

Cu2+ is reduced to Cu.

Change in oxidation state is from +2 to 0

PLEASE SOMEONE HELP ME WITH THIIS QUESTION

The labels have fallen off three bottles. Bottle A contains a gas, bottle B contains a liquid and bottle C contains a solid. The labels indicate that the compounds have the same number of carbon atoms, one being and alkane, one an alcohol, and the other a carboxylic acid. Suggest the identity of the contents of each bottle, and give reasons for your answer.

Answers

Answer:

The correct answer is - 5 carbon compounds due to low to high intermolecular forces between their molecules.

Explanation:

Bottle C has gas in it and we know that alkane has carbon and hydrogen only which means they have a single sigma bond between them and very low intermolecular forces in between molecules and are present mostly at gaseous state. Thus, bottle C has alkane.

Alcohols have -OH group that can form rarely two pi bonds which means they have intermediate intermolecular force whereas acids have -cooH group with a high molecular force so bottle B with liquid is alcohol and A has acid.

Cavendish’s name for hydrogen gas was "inflammable air." The word inflammable means "to burn." (Note that in is not a prefix in this word.) Why did Cavendish use this name?

Answers

Answer:

The gas formed in the experiment could catch fire easily. So, he named the gas inflammable air.

This was the answer straight from Plato. I hope that this helped you, please mark me the brainiest, like and rate my answer if it did! :)

Explanation:

This was the answer straight from Plato. I hope that this helped you, please mark me the brainiest, like and rate my answer if it did! :)

Answer:

The gas formed in the experiment could catch fire easily. So, he named the gas inflammable air.

Explanation: your welcome

1.37 gram of cupric oxide on reduction with hydrogen gas gives 1.098gram of copper and in next experiment 1.17 gram of copper produce 1.476gram of copper oxide illustrate this satisfy law of definite proportion

Answers

Answer: This satisfies the law of definite proportion or constant proportion and it can be proven below.

Explanation:

The law of constant or definite proportion states that all pure samples of the same compound no matter how they are made; are made up of the same elements combined in the same proportion by mass. The can be verified by finding the ratio of copper to oxygen in the both experiment listed above.

In the first experiment:

1.37 g of cupric oxide contains 1.098 g copper therefore oxygen = 1.37 − 1.098

=0.272 g

The ratio of copper to oxygen is=

1.098 ÷ 0.272

= 4:1

In the SECOND or next experiment:

1.476 g of cupric oxide contains 1.17 g copper Therefore oxygen = 1.476−1.17

=0.306g

The ratio of copper to oxygen is =

=1.176 ÷ 0.306

=3.8:1

Which is approximately≃4:1.

In conclusion, despite the different methods of the experiments, composition of copper of copper in the two different samples are the same and the cupric oxide obtained from different sources contain the same elements ( copper and oxygen) combined in the SAME ratio.

can anyone help me in my chemistry homework?​

Answers

Answer:

what is in your chemistry home work I can try for...

Answer:

1: A substance made by mixing other substances together.

2: Solutions, Suspensions, Colloids and Emulsion.

3: A particular kind of matter with uniform properties.

4: A homogenous mixture is that mixture in which the components mix with each other and its composition is uniform throughout the solution. A heterogenous mixture is that mixture in which the composition is not uniform throughout and different components are observed.

5: A solution is a homogeneous mixture of two or more components in which the particle size is smaller than 1 nm. Common examples of solutions are the sugar in water and salt in water solutions, soda water, etc. In a solution, all the components appear as a single phase.

6: A solution forms when one substance dissolves in another. The substance that dissolves is called the solute. The substance that dissolves it is called the solvent. For example, polar solvents dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes.

7: Common examples of suspension include the mixture of chalk and water, muddy water, the mixture of flour and water, a mixture of dust particles and air, fog, milk of magnesia, etc. Q2. Give the definition of suspension. Ans: A suspension is a heterogeneous mixture of two or more substances.

8: The Tyndall effect is light scattering by particles in a colloid or in a very fine suspension.

Explanation:

is c10H8 a conductor

Answers

Answer:

No

Explanation:

Napthalene cannot conduct electricity

El tipo de enlace en los compuestos: NaF , SO2 e I2 ,son respectivamente de acuerdo a sus electronegatividades que son las siguientes: Na = 0.9 F= 4.0 S= 2.6 I =2.7 F=4.0

Answers

Respuesta:

NaF: Enlace iónico

SO₂: Enlace covalente polar

I₂: Enlace covalente apolar

Explicación:

El tipo de enlace entre 2 elementos depende de la diferencia de electronegatividad.

Si ΔEN = 0, el enlace es covalente apolar.Si 0 < ΔEN ≤ 1.7 , el enlace es covalente polar.Si ΔEN > 1.7 , el enlace es covalente iónico.

NaF

ΔEN = |EN(Na)-EN(F)| = |0.9-4.0| = 3.1

El enlace es iónico.

SO₂

ΔEN = |EN(S)-EN(O)| = |2.6-3.5| = 0.9

El enlace es covalente polar.

I₂

ΔEN = |EN(I)-EN(I)| = |2.7-2.7| = 0

El enlace es covalente apolar.

. Why a chlorine atom with an atomic number of 17 will be negatively charged when its valance shell gains an electron.

Answers

Explanation:

When chlorine bonds and becomes stable, (had a full outer electron shell), because we know that chlorine has 7 electrons in it’s outer shell, it requires 1 to gain noble gas structure. So, when if bonds with an element and then becomes stable, the gaining of an electron means it becomes a negatively charged ion. (an ion being a charged particle.)

Plz Help I have One more time To retake and I can't fail it..​

Answers

Answer:

A

Explanation:

I think the answer would be A

Jack was camping. He put a can of baked beans on his campfire, without opening the lid. The can exploded. What happened?

Answers

Answer:

Too much steam expands within the can, causing it to explode

Explanation:

Beans contain water, and when water is heated, steam is created. As the steam increases, there's less and less room for it to go. The built up pressure causes the can to explode.

In the following acid-base reaction,
Cl- is the
HCI(g) + H2O(l) →H30+(aq) + Cl(aq)
acid
base
conjugate
base

Answers

Answer:

conjugate base

Explanation:

The following equation is given in this question:

HCI(g) + H2O(l) → H30+(aq) + Cl-(aq)

In accordance to Brønsted–Lowry acid–base theory, an acid is a substance that loses an hydrogen ion (H+) or proton in an aqueous solution. This theory further indicated that the substance formed after an acid loses its hydrogen ion is called a CONJUGATE BASE.

In the above equation, HCl is the acid because it loses H+ while the substance formed after the loss of H+, which is Cl- is a conjugate base.

Name the following compound NiBr2?

Answers

Answer:

the Name of NiBr2 is

Nickel(II) bromide

Nickel(II) bromide | NiBr2 - PubChem.
Synonyms: Nickel(II) bromideNickel dibromideDibromonickelNickelous bromideNickel ...
Molecular Formula: NiBr2 or Br2Ni
PubChem CID: 278492

Between reaction of magnesium powder and lead oxide which is oxidized in the reaction and which is oxidizing agent

Answers

Answer:

Mg is oxidized and Pb is the oxidizing agent

Explanation:

Why boiling point is less at hilly station?

Answers

The atmospheric pressure at high altitudes like hill station is less than at the sea level. Thus, vapour pressure will equal atmospheric pressure at a comparatively low temperature. Thus, the boiling point of water is reduced less than at sea level.

Hope it helps. Pls mark me as brainliest :D

Calculate the mass percent of carbon,oxygen, nitrogen and hydrogen in acetamide, C2H5NO.
Molar Mass:
O=16, N=14,C=12, H =1.

Answers

Answer:

40.68 % C

23.73 % N

8.47% H

27.12% O

Explanation:

The mass percent of an element X in a compound is calculated as the molar mass (MM) of X multiplied by the number of atoms of X in the compound, divided into the molecular weight (MW) of the compound, as follows:

mass percent of X = (MM(X) x number of atoms of X)/MW compound x 100

Thus, we first calculate the MW of acetamide (C₂H₅NO) by using the molar mass of the chemical elements C, H, N and O:

MW(C₂H₅NO) = (12 g/mol C x 2) + (1 g/mol H x 5) + 14 g/mol N + 16 g/mol O = 59 g/mol

Now, we can calculate the mass percent of each element (C, H, N, O) in C₂H₅NO:

Mass percent of C (2 atoms of C in 1 molecule of C₂H₅NO):

          % mass C = (12 g/mol x 2)/(59 g/mol) x 100 = 40.68 %

Mass percent of N (1 atom of N in 1 molecule of C₂H₅NO):

       % mass N = (14 g/mol x 1)/(59 g/mol) x 100 = 23.73 %

Mass percent of H (5 atoms of H in 1 molecule of C₂H₅NO):

       % mass H = (1 g/mol x 5)/(59 g/mol) x 100 = 8.47 %

Mass percent of O (1 atom of O in 1 molecule of C₂H₅NO):

       % mass O = (16 g/mol x 1)/(59 g/mol) x 100 = 27.12 %

The sum of the mass percents has to be equal to 100%:

40.68 % C + 23.73 % N + 8.47% H + 27.12% O = 100%

Describe how you would prepare a supersaturated solution

Answers

Answer:

A supersaturated solution contains more dissolved solute than required for preparing a saturated solution and can be prepared by heating a saturated solution, adding more solute, and then cooling it gently. Excess dissolved solute crystallizes by seeding supersaturated solution with a few crystals of the solute.

Explanation:

Using salt and ice to make ice cream is an example of:

Answers

Answer:

An exothermic reaction

Explanation:

1. Necesitas un "cubo concentrado" (de esos que se usan para sazonar las comidas Maggie, ricostilla) dos vasos de vidrio o plástico y agua (caliente y fría). 2.Agrega al vaso con agua fria la mitad de un cubo concentrado y déjala reposar unos minutos. Prepara el segundo vaso con agua caliente y agrégale la otra mitad del cubo. 3. Argumenta tus observaciones en relación con lo observado y con la teoria vista. ¿Como influye la temperatura en este experimento?​

Answers

Respuesta:
El cubo Maggie es un sazonador que contiene caldo de pollo y grasas, por lo que se disuelve fácilmente al entrar en contacto con el agua caliente gracias a que la temperatura que derrite las grasas y se vuelven líquidas, mientras que con el agua fría no puede disolverse así de rápido ya que las grasas siguen en estado sólido.

Cual es la longitud de onda de un foton emitido durante la transicion desde el stado n=5 al estado n=3 en atomo Hidrogeno? Dar como respuesta de la longitud de onda en nm (nanometros)

Answers

Answer:

1302 nm

Explanation:

Del formulario de Rydberg para longitud de onda

1 / λ = R (1 / nf ^ 2 - 1 / ni ^ 2)

1 / λ = 1.097 × 10 ^ 7 (1/3 ^ 2 - 1/5 ^ 2)

1 / λ = 1.097 × 10 ^ 7 (0.11 - 0.04)

1 / λ = 1.097 × 10 ^ 7 (0.07)

= 1,302 × 10 ^ -6 m

o 1302 nm

A roller coaster approaches a hill,
traveling at 40 m/s. The roller
coaster has a mass of 800 kg.
When it reaches the top of the hill,
it has exactly zero velocity. What
is the height of the hill?

Answers

Answer:

the height of the hill is 30 feet tall

what is hard water and soft water​

Answers

Answer:

Hard water is water that has high mineral content, Soft water is free from dissolved salts of such metals as calcium, iron, or magnesium

Explanation:

Hard water is water that contains a quantity of dissolved minerals e.g. calcium and magnesium.Soft water is treated water in which the only ion is sodium.

The concentration of hydronium ions is greater than 1 × 10–7 for acidic solutions. True False

Answers

The concentration of hydronium ions (H₃O⁺) is generally greater than 1 × 10⁻⁷ for all acidic solutions: True.

What is an acidic solution?

An acidic solution can be defined as a type of aqeous solution that has a high concentration of hydrogen ions (H⁺), which is typically greater than that of pure water.

As a result of the fact that an acidic solution has a power of hydrogen ions (pH) below 7, the concentration of hydronium ions (H₃O⁺) derived from the protonation of water would be greater than 1 × 10⁻⁷ for all acidic solutions.

In conclusion, we can deduce that a property of all acidic solution is a concentration of hydronium ions (H₃O⁺) that is greater than 1 × 10⁻⁷.

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the setup below was used to investigate the reaction between metals and water
i.)identify solid X and state its purpose
ii.)write a chemical equation for the reaction that produces the flame​

Answers

Answer:

I hope it helps you

Explanation:

make me brainlest

Solid X  is glass wool and is used to generate the flow of steam .Chemical equation for reaction between metal and water is metal hydroxide and hydrogen gas.

What is chemical equation?

Chemical equation is a symbolic representation of a chemical reaction which is written in the form of symbols and chemical formulas.The reactants are present on the left hand side while the products are present on the right hand side.

A plus sign is present between reactants and products if they are more than one in any case and an arrow is present pointing towards the product side which indicates the direction of the reaction .There are coefficients present next to the chemical symbols and formulas .

The first chemical equation was put forth by Jean Beguin in 1615.By making use of chemical equations the direction of reaction ,state of reactants and products can be stated. In the chemical equations even the temperature to be maintained and catalyst can be mentioned.

Learn more about chemical equation,here:

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Nồng độ mol của 200ml dung dịch Nacl chứa 0,5 mol chất tan là :

Answers

Answer:

Explanation:

2,5M

Answer:

2,5m

Explanation:

c=n:v

what mass of aluminium is produced from 100g of aluminium oxide?

Answers

Answer:

This answer is 108g mass of aluminum is produced from 100g of aluminum oxide

calculate the volume in L od 2.11mol/L CuSo4(aq) solution that contains 0.41 mol copper(2) sulfate

Answers

Answer:

0.194L

Explanation:

Molarity of a solution is its molar concentration, and can be calculated using the formula:

Molarity = no. of moles (n) ÷ volume (V)

According to this question, the molar concentration/molarity of a solution of copper sulfate (CuSO4) is 2.11mol/L and contains 0.41 mol CuSO4. The volume can be calculated as follows;

Volume = no. of moles ÷ molarity

Volume = 0.41mol ÷ 2.11mol/L

V = 0.194 liter

what is the temperature in kelvins of 23 Celsius? hurry pls

Answers

Answer:

23°C + 273.15 = 296.15K

I HOPE ITS RIGHT IF NOT THEN SORRY

HAVE A GREAT DAY :)

sodium carbonate decahydrate crystals were left exposed on a watch glass for two days

(a)name the property of salts investigated in the above experiment?

Answers

I think sublimation because sublimation is the process by which substances change back to gases immediately

where do you write salt and suger why​

Answers

Answer:

here: "salt and sugar"

Explanation:

I dunno, looks pretty, gives 5 points. even tough any context is missing

but seriously:

salt and sugar look the same. just someone with a split personality

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