What’s the difference between Fe and Fe2+?

Answer:

B

Explanation:

I studied this and had a test

Answer:

When the electrons in the atom are excited, for example by being heated, the additional energy pushes the electrons to higher energy orbitals. When the electrons fall back down and leave the excited state, energy is re-emitted in the form of a photon. The wavelength (or equivalently, frequency) of the photon is determined by the difference in energy between the two states. These emitted photons form the element's spectrum.

The fact that only certain colors appear in an element's atomic emission spectrum means that only certain frequencies of light are emitted. Each of these frequencies are related to energy by the formula:

{\displaystyle E_{\text{photon}}=h\nu }E_{\text{photon}}=h\nu ,

where {\displaystyle E_{\text{photon}}}E_{\text{photon}} is the energy of the photon, {\displaystyle \nu }\nu  is its frequency, and {\displaystyle h}h is Planck's constant. This concludes that only photons with specific energies are emitted by the atom. The principle of the atomic emission spectrum explains the varied colors in neon signs, as well as chemical flame test results (described below).

The frequencies of light that an atom can emit are dependent on states the electrons can be in. When excited, an electron moves to a higher energy level or orbital. When the electron falls back to its ground level the light is emitted.

Explanation:

Answer:

Amino Acids

Explanation:

What Are Proteins Made Of? The building blocks of proteins are amino acids, which are small organic molecules that consist of an alpha (central) carbon atom linked to an amino group, a carboxyl group, a hydrogen atom, and a variable component called a side chain.

Answer:

Amino Acids

Explanation:

Answer:

same valency electrons

Explanation:

example g 1 elements

Answer:

Explanation:

The force acting on an object given the mass and acceleration we use the formula

From the question

mass = 142 g = 0.142 kg

acceleration = 9 m/s²

We have

force = 0.142 × 9 = 1.278

We have the final answer as

Hope this helps you

Answer:

1.28

Explanation:

In order for you to get the force you have to multiply the mass & acceleration. The baseball mass is 142 g and the acceleration is 9. So you will calculate 0.142 x 9 and that will give you 1.278. You will then round the 7 to an 8 and then you get the answer 1.28.

Answer:

As it is given that

[tex]activity=\lambda= 100\\[/tex]

[tex]Number~of ~counts=100/second\\[/tex]

Using formula

[tex]ln(\frac{N}{N_o})=-\lambda\cdot t\\\\[/tex]

or

[tex]-\frac{ln(\frac{N}{N_o})}{\lambda}= t\\\\[/tex]

where [tex]N=\frac{N_o}{3}[/tex]

[tex]-\frac{ln(\frac{1}{3})}{100}= t\\\\\-\frac{-1.0986}{100}=t\\\\[/tex]

[tex]\frac{1.0986}{100}=t\\1.0986\cdot 10^{-2}seconds=t\\[/tex]

Answer:

Explanation:

A stereoisomer refers to an isomer that shares an identical bonding structure but differs in the geometric position of functional groups and atoms.

Stereoisomers are molecules which have the same semi-expanded formula, but a different arrangement in space.

They are isomers with a similar structural formula, yet which contrast just in their spatial geometry.

From the given question, we are provided with some set of instructions to draw the structure of the following compounds.

stereoisomer of trans-1,2-dibromocyclobutane

cis-1,2-dimethylcyclopentane

cis-1,2-dimethylcyclobutane

The diagram for each compound given can be seen in the attached file below.

Answer:

216g H2O

Explanation:

H = 1

O = 16

H= 2 × 1 = 2

O= 1 × 16 = 16

16 + 2= 18g/mol

18g H2O = 1 mol

X g H2O = 12 mol

X × 1 = 18 × 12

X = 216 g/mol

The weight of 12.0 moles of water is determined as 216 g.

The weight of water is determined from the molecular weight of water. The molecular weight of water is given 18 g/mol.

The weight of 12 moles of water is calculated as follows;.

W = nM

W = 12mole x 18 g/mol

W = 216 g

Thus, the weight of 12.0 moles of water is determined as 216 g.

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Answer:

cell membrane is the answer

Answer: cell membrane

Explanation:

Answer: 0.275 moles

Explanation: Na- 22.99g (on periodic table)

O- 16g and H- 1.01

22.99 + 16 + 1.01 = 40g/mol of NaOH

11g of NaOH / 40g / mol of NaOH = 0.275mol NaOH

Answer:

HCl + Mg(OH2)  ---> MgCl2 + H2O

Explanation:

hydrochloric acid + magnesium hydroxides  ==> magnesium Chloride (a salt) + Water

HCl + Mg(OH2)  ---> MgCl2 + H2O

Answer:

metal atoms lose electrons to form positivity charged ions. non metal atoms gain electrons to form negatively charged ions

Answer:

A mixture.

Explanation:

The image contains two types of molecules: one with a blue centre and one with a green centre. They are both compounds, as they contain atoms of different elements that are chemically combined/ bonded to each other. As the molecules of the different compounds are not bonded to each other, the model must show a mixture.

A mixture: a combination of molecules of different elements and/or compounds that are not chemically combined e.g. salt dissolved in water.

An element: a substance containing only one kind of atom e.g. oxygen.

A compound: a substance containing two or more kinds of atoms (atoms of different elements) are chemically bonded to each other e.g. water.

In the model of an element, it represents a mixture. The correct option is b.

A mixture is a non-chemically coupled combination of molecules from different elements and/or compounds, such as salt dissolved in water.

There are two kinds of molecules in the image: one with a blue center and one with a green center. They are both compounds because they contain atoms of different elements that have been chemically combined/bonded. Because the molecules of the various compounds are not bound to one another, the model must depict a mixture.

A compound is a substance that contains two or more types of atoms (atoms of different elements) that are chemically bound to one another, such as water.

Therefore, the model shows a mixture.

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Answer:The physical changes that are endothermic are melting, vaporization and sublimation.

Explanation:

Answer:

Noble gas, any of the seven chemical elements that make up Group 18 (VIIIa) of the periodic table. The elements are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og).

Explanation:

I pretty much covered it in my answer!

Pls Brainliest! It would mean a lot! ;)

Answer:

The answer is D.

Explanation:

I learned about this last year. Its very simple if you let your parents or teachers explain it to you!

Answer:

All of the above

Explanation:

All the answers are correct. Lipids come in difference forms.

Answer:

4.52×1000=4520

Explanation:

4.52*1000=4520

Answer:

Tings that effect weather is basically the following:

Answer:

(1) the same chemical properties .

Explanation:

Hello!

In this case, among the options:

(1) the same chemical properties

(2) the same volume

(3) different temperatures

(4) different empirical formulas

We can see that they have the same chemical properties as they at the same conditions, same type of bond (polar), molecular geometry, bond angle (104.5 °) and so on. Nevertheless, at STP (1 atm and 273.15 K) they do not have the same volume since the larger the mass, the larger the volume, they have the same temperature and the both of them are H₂O.

It means that the answer is (1) the same chemical properties .

Best regards.

Answer:

x

Explanation:

becaue neutron equal to mass num -atomic num

Answer: median :4.44 mean :4.11

Explanation:

i did test on Edge

The elastic potential energy of the spring will be two times greater than the gravitational potential energy of the object.

Answer:

C.) The elastic potential energy of the spring will be two times greater than the gravitational potential energy of the object.

Explanation:

Hope this helps! Sorry if I am wrong. ;-;

Answer:

0.8M

Explanation:

Given parameters:

Number of moles of KNO₃  = 0.2mol

Volume of KNO₃ = 250mL

Unknown:

Molarity of the solution  = ?

Solution:

The molarity of a solution is the number of moles in a given volume of a solution;

         Molarity  = [tex]\frac{number of moles }{volume}[/tex]

 We need to convert the given volume to L;

                1000mL  = 1L

        250mL will give  250 x 10⁻³L = 0.25L

So;

        Molarity  = [tex]\frac{0.2}{0.25}[/tex]   = 0.8M

Answer:

0.8 M

Explanation:

The formula is mol divided by liters. Converting 250 ml to .25 liters is important. Dividing .2 by .25 gets the answer. (I swear it’s right but it’s graded wrong so take this with a grain of salt)

Answer: Sodium chloride

Explanation:

Ocean water contains a number of substances. When a substance which has ionic bonds is dissolved in water it takes the form of ions.

The most common ions in ocean water are sodium and chloride. These are the ions formed when common salt, sodium chloride (NaCl) is dissolved in water.

Sodium chloride accounts for about 3% of ocean water by mass.

Answer:

By far, the most abundant elements are hydrogen and water.

Explanation:

The analysis of the 77 sea water samples taken during the Challenger's 3-year voyage did much to lay the foundations for determining the chemical content of sea water. By far, the most abundant elements are hydrogen and water (combined to make water). Together, these elements make up 96% of sea water. Sodium chloride and magnesium make up just under 4% of sea water. Trace amounts of 97 other elements are found in the remaining 0.08%. Of the trace elements, calcium, potassium, sulfur, and bromine are the most abundant.

This is directly from the text.

Answer:

i cant see what it says

Explanation:

OUTLINE

Paragraph 1: Introduction

Paragraph 2: Body Paragraph

Paragraph 3: Body Paragraph

Paragraph 4: Body Paragraph

Paragraph 5: Conclusion

Think of the introduction and conclusion as “bookends” that serve to hold the essay tightly together. The

introduction will “push” into or initiate the examination of your topic and the angle you decide to focus on, while

the conclusion will “pull” tight all the ideas that you have gathered together for a unified essay.

Remember, the five-paragraph model can be expanded to include more body paragraphs that probe more deeply

into your subject. Check with your instructor to ensure whether or not you can exceed this length for an

assignment.

The introductory paragraph should include the following elements:

Background information: Enough information necessary for your reader to understand your topic

Thesis statement: Indicates your paper’s topic, makes your paper’s purpose clear, and provides an

overview of the three main supporting points that will unify the essay. The thesis statement is typically

the last sentence.

If you are writing in response to a text, the introduction should include the title, author, and genre of that

piece.

Begins with a topic sentence that identifies one main idea that will be discussed as support or proof for the

thesis statement

Supporting sentences use specific details, demonstrated through closely related examples or evidence, to

expand and explain the main idea. Generally, a well-developed paragraph has at least five to eight

sentences.

Paragraph unity means that all ideas in a paragraph are closely related to its topic sentence and further

develop that topic sentence. That is, all sentences in a single paragraph must be unified around a central

point or idea.

This paragraph, and any subsequent body paragraph, should begin with a topic sentence that signals the

reader that a new idea or point is being introduced.

As you organize your essay, keep in mind its coherence. Coherence refers to connections among

paragraphs and ideas—the logical sequence of your thoughts.

o Use transition words or phrases at the outset of your body paragraphs and to move from one idea

to another within your paragraphs.

o Have you transitioned logically from the main idea in the previous paragraph to this one? Are you

making clear connections among the paragraphs and ideas? Be sure to think about coherence during

the revision stage of the writing process.

This paragraph begins with the final topic sentence that relates back to the remaining point mentioned in the

thesis statement. Each paragraph should contain a new main idea.

Again, flesh out this main idea with specific examples, details, and relevant support.

Be sure to maintain paragraph unity. That is, each sentence must relate to your topic sentence.

The conclusion revisits your overall purpose for writing and often invites your reader to consider the

implications of why your ideas are significant.

The conclusion may restate the thesis, summarize the paper’s major points, or leave the reader with a final

thought to ponder. Several other methods for writing conclusions are included on a separate Tutoring Center

handout. If you choose to restate the thesis or summarize the essay’s main ideas, do not repeat the same

wording from the introduction or body paragraphs. Remember not to introduce new, unrelated ideas in the

conclusion

Answer:

answer explained below.

Explanation:

hey! a molecule is made up of two or more atoms, and a compound is made up of two or more elements. not all molecules are compounds, but all compounds are molecules, because compounds are made up of different atoms.

example: O2 is a molecule but not a compound because it is made up of the same element, but has more than one atom.

Explanation:

Some examples of colorful light emissions are street lights, neon signs and, of course, fireworks. Neon signs emit light when an electric current passes through the neon gas.