Describe the two categories used to classify physical changes.

Answers

Answer 1

Answer:

Physical changes can be classified as reversible or irreversible. Melting is an example of a reversible physical change.

Explanation:


Related Questions

the total charge of an atom comes from
a) protons only
b) neutrons only
c) protons and neutrons
d) protons and electrons

Answers

The total charge on an atom comes from protons and electrons.

The proton is positively charged while the electron is negatively charged. A neutral atom would have an equal number of protons and electrons.

An atom with more protons than electrons will be positively charged while those with more electrons than protons will be negatively charged.

More on the atom can be found here:  https://brainly.com/question/1641336

What is the molar mass of an unknown gas with a density of 3.35 g/L at 1.00 atm and 25.0 °C

Answers

Answer:

[tex]\implies \sf D = \dfrac{PM}{RT}[/tex]

[tex]\implies \sf 3.35= \dfrac{1 \times M}{ \frac{1}{12} \times 298}[/tex]

[tex]\implies \sf 3.35= \dfrac{12\times M}{ 298}[/tex]

[tex]\implies \sf 3.35 \times 298= 12\times M[/tex]

[tex]\implies \sf 998.3= 12\times M[/tex]

[tex]\implies \sf M = \dfrac{998.3}{12} [/tex]

[tex]\implies \bf M = 83.1917 \: \frac{g}{mol} [/tex]

(only the rght letter and a explanation you don't really need the explanation ill give brainiest)
What happens when an electrically charged pencil is placed close to water running from a faucet?

A. The pencil attracts the water.
B. The pencil becomes positively charged.
C. The water attracts the pencil.
D. The water repels the pencil.

Answers

Answer:

Explanation:

Option c)  The water attracts the pencil.  

Pencils are though formed of wood that acts as a bad conductor of electricity, quite strangely pencils can be electrically charged.

Here pencils have non-metal carbons present in its graphite tip and this makes the pencils charged.

When this pencil is held near the water of the tap, the hydrogen ions get attracted and thereby the water gets attracted to the pencil.

Water, however, is an excellent conductor of electricity and therefore water and electricity are a dangerous combination.

Someone know the answer for that question

Answers

Anything that takes up space so C

What happens to the 3 carbons in the krebs cycle.

Answers

Answer:

Tthe 3-carbon pyruvate molecule made in glycolysis loses a carbon to produce a new, 2-carbon molecule called acetyl CoA. The carbon that is removed takes two oxygens from pyruvate with it, and exits the body as carbon dioxide (CO 2​start subscript, 2, end subscriptt).

Explanation:

why is transfer of the heat by the actual movement of the warmed matter

Answers

Answer:

The warmer the water gets the particles begin to expand and starts vibrating

How are covelant and ionic bonds different and what types of elements combine to form each?

Answers

Answer:

Ionic bonds result from the transfer of electrons from one atom to another

Explanation:

In covalent bonds, atoms share electrons, whereas in ionic bonds atoms transfer electrons. The reaction components of covalent bonds are electrically neutral, whereas for ionic bonds they are both charged.Covalent bonds are formed between two non-metals, whereas ionic bonds are formed between a metal and non-metal.  

Answer:

Covalent bonds are defined as sharing of electrons, ionic bonds are the result of transferred electrons;

Covalent bonds form between non-metals (elements) and ionic bonds form between metal and non-metals (ions)

Question 4 of 5
Which characteristic describes the living things in the domain Eukarya?
A. They can be made up of prokaryotic cells.
B. They are made up of eukaryotic cells.
C. They are all multicellular organisms.
D. They are made up of cells that lack a nucleus.
SUBMIT

Answers

Answer:

he presence of nucleus which contains genetic material and is enclosed by a nuclear membrane sets them apart from prokaryotic cells. All complex organisms are eukaryotic and they reproduce by mitosis or meiosis. Eukaryotic cells are typically much larger than those of prokaryotes.

Explanation:

2. Choose the atom from each of the following pairs with the greater ionization energy: a. Be and Ba b. Al and Ar c. Ca and Cl

Answers

Considering the definition of ionization energy, the highest ionization energy belongs to the element:

a. Be

b. Ar

c. Cl

Electrons are held in atoms by their attraction to the nucleus, which means that energy is needed to remove an electron from the atom.

You should keep in mind that the electrons of the last layer are always lost, because they are the weakest attracted to the nucleus.

Ionization energy, also called ionization potential, is the necessary energy that must be supplied to a neutral, gaseous, ground-state atom to remove an electron from an atom. When an electron is removed from a neutral atom, a cation with a charge equal to +1 is formed.

In a group, the ionization energy increases upwards because when passing from one element to the bottom, it contains one more layer of electrons. Therefore, the valence layer electrons, being further away from the nucleus, will be less attracted to it and it will cost less energy to pluck them.

In the same period, in general, it increases as you shift to the right. This is because the elements in this way have a tendency to gain electrons and therefore it will cost much more to tear them off than those on the left which, having few electrons in the last layer will cost them much less to lose them.

Considering all the above, from each of the pairs, the highest ionization energy belongs to the element:

a. Be

b. Ar

c. Cl

Learn more:

brainly.com/question/16243729?referrer=searchResults brainly.com/question/11623163?referrer=searchResults brainly.com/question/1602374?referrer=searchResults

What is the charge for H before electron share?

Answers

An H atom is made up of a nucleus with a +1 charge, as well as a single electron. Therefore, the only positively charged ion possible has charge +1.

I hope this helps!

Describe the procedural steps to achieve adequate separation of a homogeneous, liquid mixture containing benzoic acid, n-propylbenzene, and phenol, provided a 4:1 hexane to ethyl acetate solution as the eluent, using Thin Layer Chromatography (TLC).

Answers

n-propylbenzene will travel the largest distance because it interacts most effectively with the stationary phase followed by phenol and benzoic acid will travel the least distance because it interacts poorly with the mobile phase.

Thin layer chromatography involves the separation of a mixture using a stationary phase made of  silica gel on a glass plate and an appropriate mobile phase. The extent of separation is highly dependent on the magnitude of interaction between the solute and the mobile phase. and stationary phase.

The first step in thin layer chromatography is to make a thin mark at the bottom portion of the plate then spot the plate with the sample. The mobile phase is now introduced into the TLC chamber a little below the mark. The plate is now placed in the stationary phase such that the mark is above the solvent level.

The TLC chamber is now covered and enough time is allowed for separation to occur. The spots can be seen using a suitable indicator dye or with a the aid of UV light

After the  separation of a homogeneous, liquid mixture containing benzoic acid, n-propylbenzene, and phenol, provided a 4:1 hexane to ethyl acetate solution as the eluent, we can see that n-propylbenzene will travel the largest distance because it interacts most effectively with the stationary phase followed by phenol and benzoic acid will travel the least distance because it interacts poorly with the mobile phase.

Learn more: https://brainly.com/question/967776

What is the unabbreviated electron configuration for Barium?

Answers

Answer:

[Xe] 6s2

Explanation:

hope it helps Electron configuration


What do all atoms in a period (horizontal rows) have in common?

Answers

Answer:

the same number of atomic orbitals.

Explanation:

Answer:

All of the elements in a period have the same number of atomic orbitals. For example, every element in the top row (the first period) has one orbital for its electrons. All of the elements in the second row (the second period) have two orbitals for their electrons.

hope this helps

if it does please mark brianliest

2.8 dm3 of gas X at STP has equal mass with 11.2 dm3 of C2H6 at STP. What is
the number of mole if gas X has 30 grams?

Answers

Answer: o.125 moles of gas X with a molar mass of 240

Explanation:

2.8 dm3 of gas X at STP has equal mass with 11.2 dm3 of C2H6 at STP. What is the number of mole if gas X has 30 grams?

the molar volume of any gas at STP is the volume of 1 mole at STP

and is 22.4 L

the C2H6 has a volume of 11.2L at STP so it has 0.5 moles

C2H6 has a molar mass of (2 X 12) +(6 X 1) = 24 + 6 = 30

0,5 moles weighs 15 gm at STP with

so 15 gm at STP with 2.8 L for gas X

PV=nRT

P=1 atm

T =273.2k

V =2.8

R =0.082

n = PV/RT = (1 X 2.8)/(0.082 X 273.2) =0.125 moles of gasX

the weight of gas X is 30 gms

so 30/.125 =240 g/mole = molar mass of gas X

Which describes an element?


They cannot be broken down any further.

They can combine with other elements to form atoms.

They were all discovered at the same time.

They were created in the Earth’s core.

Answers

Answer: They cannot be broken down any further

Answer:

They cannot be broken down any further

Explanation:

An element is a substance that cannot be broken down into a simpler format. They are distinguished by a unique atomic number. The elements are organized by their atomic number in the periodic table, which highlights elements with similar properties.

The equation for the reaction between magnesium and hydrogen is written below
mg+2hcl------mgcl (2)+H (2)
(1) what mass of magnesium would be needed to give 50g of hydrogen? (mg=24, H=1)
(2) what volume would this gas occupy at s.t.p​

Answers

Answer:

Explanation:

The balanced equation says that we'll get 1 mole of H2 for every 1 mole of Mg.  50 grams of H is 50g/2 g/mole = 25 moles of H2.  That means we'll need 25 moles of Mg.  Convert that into grams:  (25 moles Mg)*(24.3 g/mole) = 607 grams Mg.  

At STP, all gases occupy 22.4 liters/miole.  That means 25 moles of H2 would occupy (25 moles)*(22.4 liters/mole) = 560 liters.

when creating a calculated column in a pivottable, where does the calculated field appear?

Answers

Answer:

A calculated field will appear in the field list window, but will not take up space in the source data. In the example shown, a calculated field called "Unit Price" has been created with a formula that divides Sales by Quantity. The pivot table displays the calculated unit price for each product in the source data.

Explanation:

The PivotTable Field List contains calculated fields. Items from other fields that have been calculated display as items.

What are calculated fields?

Calculated fields are defined as the fields whose values are determined by other fields' values and perhaps external sources. Data from other fields can be calculated using calculated fields. Calculating the sum of two fields is a simple example, but more complicated calculations, such averaging values from multiple tables or even gaining access to external data, are theoretically feasible.

PivotTable Field List is defined as the Areas part of the Field List allows you to organize the fields wherever you like. It features a field section where you select the fields you wish to display in your PivotTable. Using a pivot table is an interactive method for quickly summarizing enormous amounts of data.

Thus, the PivotTable Field List contains calculated fields. Items from other fields that have been calculated display as items.

To learn more about calculated fields, refer to the link below:

https://brainly.com/question/13668122

#SPJ2

A mixture of molten salts contains the following ions: Mg2 , Cu2 ,F-, Cl-, Br-. Which ion will be oxidized first, when the mixture undergoes electrolysis.

Answers

When the mixture of ions undergoes electrolysis, Br- is most easily oxidized.

Electrolysis refers to the decomposition of a solution by the passage of direct current through it. During electrolysis, a specie is oxidized and another specie is reduced since it is a redox reaction.

Among all the ions; Mg2+ , Cu2+ ,F-, Cl-, Br-, the ion that is most easily oxidized in Br- which is oxidized to Br2.

Learn more: https://brainly.com/question/12054569

what are anibiotcs made of
just interested

Answers

Answer:

please mark as brainliest

Explanation:

Any substance that inhibits the growth and replication of a bacterium or kills it outright can be called an antibiotic. Antibiotics are a type of antimicrobial designed to target bacterial infections within (or on) the body. This makes antibiotics subtly different from the other main kinds of antimicrobials widely used today:

Antiseptics are used to sterilise surfaces of living tissue when the risk of infection is high, such as during surgery.

Disinfectants are non-selective antimicrobials, killing a wide range of micro-organisms including bacteria. They are used on non-living surfaces, for example in hospitals.

Of course, bacteria are not the only microbes that can be harmful to us. Fungi and viruses can also be a danger to humans, and they are targeted by antifungals and antivirals, respectively. Only substances that target bacteria are called antibiotics, while the name antimicrobial is an umbrella term for anything that inhibits or kills microbial cells including antibiotics, antifungals, antivirals and chemicals such as antiseptics.

Most antibiotics used today are produced in laboratories, but they are often based on compounds scientists have found in nature. Some microbes, for example, produce substances specifically to kill other nearby bacteria in order to gain an advantage when competing for food, water or other limited resources. However, some microbes only produce antibiotics in the laboratory

Answer:

Antibiotics commonly are produced by soil microorganisms and probably represent a means by which organisms in a complex environment, such as soil, control the growth of competing microorganisms. Microorganisms that produce antibiotics useful in preventing or treating disease include the bacteria and the fungi.

Explanation:

source: trust me bro

how does water's structure explain its properties?

Answers

We know that water is tasteless, odorless, and transparent. In small quantities, it is also colorless. However, when a large amount of water is observed, as in a lake or the ocean, it is actually light blue in color. The blue hue of water is an intrinsic property and is caused by selective absorption and scattering of white light. These and other properties of water depend on its chemical structure.The transparency of water is important for organisms that live in water. Because water is transparent, sunlight can pass through it. Sunlight is needed by water plants and other water organisms for photosynthesis.Chemical Structure of WaterEach molecule of water consists of one atom of oxygen and two atoms of hydrogen, so it has the chemical formula H2O. The arrangement of atoms in a water molecule explains many of water’s chemical properties. In each water molecule, the nucleus of the oxygen atom (with 8 positively charged protons) attracts electrons much more strongly than do the hydrogen nuclei (with only one positively charged proton). This results in a negative electrical charge near the oxygen atom (due to the "pull" of the negatively charged electrons toward the oxygen nucleus) and a positive electrical charge near the hydrogen atoms. A difference in electrical charge between different parts of a molecule is called polarity. A polar molecule is a molecule in which part of the molecule is positively charged and part of the molecule is negatively charged.

•Hydrogen Bonding-

Opposite electrical charges attract one another. Therefore, the positive part of one water molecule is attracted to the negative parts of other water molecules. Because of this attraction, bonds form between hydrogen and oxygen atoms of adjacent water molecules. This type of bond always involves a hydrogen atom, so it is called a hydrogen bond. Hydrogen bonds are bonds between molecules, and they are not as strong as bonds within molecules. Nonetheless, they help hold water molecules together.

•Sticky, Wet Water-

Water has some unusual properties due to its hydrogen bonds. One property is cohesion, the tendency for water molecules to stick together. The cohesive forces between water molecules are responsible for the phenomenon known as surface tension. The molecules at the surface do not have other like molecules on all sides of them and consequently they cohere more strongly to those directly associated with them on the surface. For example, if you drop a tiny amount of water onto a very smooth surface, the water molecules will stick together and form a droplet, rather than spread out over the surface. The same thing happens when water slowly drips from a leaky faucet. The water doesn't fall from the faucet as individual water molecules but as droplets of water.

•Density of Ice and Water-

The melting point of water is 0°C. Below this temperature, water is a solid (ice). Unlike most chemical substances, water in a solid state has a lower density than water in a liquid state. This is because water expands when it freezes. Again, hydrogen bonding is the reason. Hydrogen bonds cause water molecules to line up less efficiently in ice than in liquid water. As a result, water molecules are spaced farther apart in ice, giving ice a lower density than liquid water. A substance with lower density floats on a substance with higher density. This explains why ice floats on liquid water, whereas many other solids sink to the bottom of liquid water.In a large body of water, such as a lake or the ocean, the water with the greatest density always sinks to the bottom. Water is most dense at about 4°C. As a result, the water at the bottom of a lake or the ocean usually has temperature of about 4°C. In climates with cold winters, this layer of 4°C water insulates the bottom of a lake from freezing temperatures. Lake organisms such as fish can survive the winter by staying in this cold, but unfrozen, water at the bottom of the lake.

Hope it helps

How many atoms are in 2.05 g of Na?
How many grams are in 4.5 x 1025 atoms of P?

Answers

THIS IS UR ANSWERPLS MARK ME AS BRAINLIEST..

I need helpppp pleaseeee!!

Answers

Answer:

Box#:

1:CoS

2:Co2S3

3:CoSO4

4:Co2(SO4)3

5:CoSO3

6:Co2(SO3)3

Explanation:

1:Co(II) is -2 and S is -2, so the charges cancel

2:Co(III) is -3 and is -2, so you cross the charges but do not reduce

3:Co(II) is -2 and SO4 is -2, so the charges cancel

4:Co(III) is -3 and SO4 is -2 so the charges cross but do not reduce

5:Co(II) is -2 and SO3 is -2 so the charges cancel

6:Co(III) is -3 and SO3 is -2 so the charges once again cross

Answer:

Cobalt (II) sulfide → CoS

Cobalt (III) sulfide → Co₂S₃

Cobalt (II) sulfate → CoSO₄

Cobalt (III) sulfate → Co₂(SO₄)₃

Cobalt (II) sulfite → CoSO₃

Cobalt (III) sulfite → Co₂(SO₃)₃

is this correct? ...​

Answers

Yes….. very correct well done………. Well then bye

When an ionic compound forms, the ions come together so that the compound is _____.

Answers

Answer:

The awnser is Ionic bond

Protons
Charge:

Mass:

Location:

Role in the atom:

Answers

Answer:

Protons are positively charged. The mass is slightly lower than a neutron.The location of a proton is nucleus. The the role of a proton is to help bind the nucleus together.

Explanation:

what is the molecular formula for sodium sulphur and oxygen​

Answers

Answer: Na2SO4

The molecular formula for sodium sulphur and oxygen​ is: (Na2SO4)

,  Hope this helps :)

Have a great day!!

WILL MARK BRAINLIEST
Georgia completed an investigation about different forces and came up with an explanation. What does she need to support her explanation?

Problem
Conclusion
Question
Evidence

Answers

Georgia needs evidence

Georgia completed an investigation about different forces and came up with an explanation. What does she need to support her explanation?

Evidence

Help please, take a screenshot who will answer will be brainiest.

Answers

Answer:

1:

•a typical metal tends to have a higher melting and boiling point than a typical non metal which has a low melting and boiling point

•a typical metal tends to have a shiny appearance than a typical non metal which has a dull apearance

•and finally, a typical metal is a good conductor of electricity and heat while a typical non metal isn't

2:

elements E and C

3:

a, it doesn't conduct electricity

b, it's a good conductor of heat/ has a high melting point/ has a high boiling point (you can choose either that sits right with you)

MULTIPLE CHOICE QUESTION
Which of the above represents a cell in an
isotonic solution?
B
А
C

Answers

Answer:

B

Explanation:

A student conducts an experiment to separate water into hydrogen and oxygen through a chemical reaction as shown below.

H Hydrogen gas Orygengu rises in this test tube test tube.

2 H2O --> 2H2 + O2

As a result the student collects 28.0 g of hydrogen and 224.0 g of oxygen. How many grams of water did the student originally start with?

Answers

The amount, in grams, of water, that the student originally started with would be 252 g

From the balanced equation of the reaction, the ratio of H2O to H2 is 1:1. Thus for every 1 mole of water that is separated, 1 mole of H2 is produced.

Recall that: mole = mass/molar mass

Mole of 28.0 g H2 produced = 28/2

                                              = 14 moles

Equivalent mole of H2O would, therefore, be 14 moles.

Mass of 14 moles H2O = mole x molar mass

                                      = 14 x 18

                                      = 252 g

More on stoichiometric calculation can be found here:  https://brainly.com/question/8062886?referrer=searchResults

Other Questions
How did exploration strengthen the kings of Europe? 5. Use the quadratic model y = -4x^2 - 3x + 4 to predict y if x equals 5.A. -89B. -111C. -411D. -51 Hi can someone help me with my project plz I cant understand this Senate advises on treaties and all ______ appointments to courts , etc. Thank-you letters should be sent out withinof the interview.O A. one weekB. one dayC. one monthD. a few days speech on what is more important being right or being more popular what's the answer to Select ALL the correct answers.Consider the graph of function g below.Determine which sequences of transformations could be applied to the parent function f(x) = x to obtain the graph of g. Shift right 2 units, reflect over x-axis, and then vertically stretch by a factor of 3. Shift left 2 units, reflect over x-axis, and then vertically stretch by a factor of 3. Shift right 6 units, reflect over x-axis, and then vertically stretch by a factor of 3. Reflect over the y-axis, vertically stretch by a factor of 3, and then shift up 6 units. Reflect over the x-axis, vertically stretch by a factor of 3, and then shift up 6 units. Shift up 6 units, reflect over the x-axis, and then vertically stretch by a factor of 3. What does Ender decide he must do about bullies? Why? (ENDERS GAME ) An example of kinetic energy being converted into heat energy What is the y-coordinate of the solution of the system of equations?Sy= 3x 262x y = 19Enter your answer in the box.y= plz help Yo _[blank 1]_ Paulo. _[blank 2]_ de Per. _[blank 3]_ muy alegre hoy, porque voy a un concierto. _[blank 4]_ en el Parque Central a las ocho. Opa! Qu hora _[blank 5]_?Qu palabra (ser o estar) completa cada oracin correctamente? What goes in what blank here are the choses Esta esta EsesSoysoy Estoyestoy "Think About Pardoning Me" Every year the president of the United States pardons a turkey. Pardon means to be cleared, freed, or let go. Assume the role of a turkey and write a formal letter to the President explaining why you should be pardoned.DOESN'T HAVE TO BE SO LONG ( 1 paragraph ) A company's biggest vulnerability in employing a best-cost provider strategy A. relying too heavily on outsourcing. B. getting squeezed between the strategies of firms employing low-cost provider and high-end differentiation strategies. C. getting trapped in a price war with low-cost leaders. D. being too timid in cutting its prices far enough below high-end differentiators many of their customers. E. not having a sustainable distinctive competence in cost reduction. A report that details prevention, appraisal, internal failure, and external failure costs is called a ________. do the write a relation as a set of five ordered pairs then express the relation using a: table mapping diagram graph What is 8.798 rounded to the nearest cent Solve it by Substitutionno link or website a well download for the answer. please do step by step If Rick did not drive to the city, the alternative was to take the train.a. development b. hazard c. compulsion d. choice 66Chapter 6 DiscussionntsThis discussion will require you to do an experiment with a friend or a member of your family. This experiment issuggested by Stanley Coren and his associates to demonstrate Weber's law (Coren, S., Ward, L., & Enns, J.T. (2003)Sensation and perception (6th edition) New York: Wiley.)etYou need three quarters, two envelopes, and a pair of shoes (preferrably heavier than a tennis shoe).1. Place one quarter in one envelope and the remaining two quarters in the other2. Have the person lift each envelope and tell you which is heavier3. Have the person go away or turn around, and then place each of the envelopes into separate shoes4. Have the person lift each shoe and tell you which is heavierurces. What were your results? Why? What was at work here? Describe how this principle might impact other areas of our everyday lives. Give at least three specific examples.Respond to at least one other classmate. David wants to purchase some pens. The pens he likes cost $2 each, not including tax. This is represented by the graph below. Write an equation for the graph of the line.