which choice is an element? Air, oxygen, water, or sodium cholride

Answers

Answer 1

Answer:

Oxygen is an element.

Explanation:

Out of the choices listed, oxygen is the only element. The other choices are incorrect because air is a mixture of nitrogen, oxygen, carbon dioxide, water vapors, and some other gases; water is a compound of hydrogen and oxygen; and sodium chloride is a compound of sodium and chloride ions; meanwhile, oxygen is a pure element.


Related Questions

Which procedure would produce the best data for comparing the electrostatic forces between the molecules of different substances?
Heat each substance in liquid form for the same amount of time. Measure the temperature of each substance.
Heat each substance in liquid form to its boiling point. Measure the temperature of each substance.
Heat each substance in solid form to its melting point. Measure the quantity of each substance that has melted.
Heat each substance in solid form for the same amount of time. Measure the temperature of each substance.

Answers

The best data for comparing the electrostatic forces between the molecules of different substances can be obtained through this procedure: B. Heat each substance in liquid form to its boiling point. Measure the temperature of each substance.

An electrostatic force can be defined as a force of attraction or repulsion between two (2) stationary and electrically charged particles of a substance.

Basically, the force between two (2) charges is inversely proportional to the square of the distance between them and directly proportional to the magnitude of their charges.

In the molecule of a substance, an electrostatic force is mainly responsible for holding its atoms together while giving the molecule both structure and strength.

During an experiment that is aimed at obtaining the best data to compare the electrostatic forces between the molecules of different substances, the procedure that should be adopted include:

Each of the substance should be heated in liquid form to its boiling point.The boiling temperature of each substance should be measured and recorded.From the data, a comparison should be done to know which molecule contain atoms that are tightly held together.

Read more: https://brainly.com/question/24031197

Answer:

B. Heat each substance in liquid form to its boiling point. Measure the temperature of each substance.

Explanation:

Just in case you couldn't find the answer. <3

what is meant by pure substance????​

Answers

Pure substance means substance is made of one type of molecules.Or you can tell it that the heterogeneous mixtures of molecules are called pure substances.For example:-Hydrogen,water ,all elements and compounds

for a molecule to exhibit hydrogen bonding the h must be covalently bonded to a?

Answers

Answer:

: fluorine, oxygen, or nitrogen.

Explanation:

Hydrogen bonding occurs only in molecules where hydrogen is covalently bonded to one of three elements: fluorine, oxygen, or nitrogen.

Hydrogen bonding occurs only in molecules where hydrogen is covalently bonded to one of three elements: fluorine, oxygen, or nitrogen. These three elements are so electronegative that they withdraw the majority of the electron density in the covalent bond with hydrogen, leaving the H atom very electron-deficient. The H atom nearly acts as a bare proton, leaving it very attracted to lone pair electrons on a nearby atom.

Based on the balanced chemical equation shown below, determine the mass percent of Fe3+ in a 0.6450 g sample of iron ore, if 22.40 mL of a 0.1000 M stannous
chloride, SnCl2(aq), solution is required to completely react with the Fe3+ present in the ore sample. The chemical equation for the reaction is
2 Fe3+ (aq) + Sn2+ (aq) →2Fe2+ (aq) + Snº+(aq).
O 19.40%
O 6.196%
O 38.79%
O 9.697%

Answers

Answer:

38.9%

Explanation:

below, determine the mass percent of Fe3+ in a 0.6450 g sample of iron ore, if 22.40 mL of a 0.1000 M stannous chloride, SnCl2(aq), solution is required to completely react with the Fe3+ present in the ore sample. The chemical equation for the reaction is

2 Fe3+ (aq) + Sn2+ (aq) →2Fe2+ (aq) + Snº+(aq).

O 19.40%

O 6.196%

O 38.79%

O 9.697%

 2 Fe3+ (aq) + Sn2+ (aq) →2Fe2+ (aq) + Snº+(aq).ole of Sn2+

for every mole of Sn2+, tere are 2 moles of Fe3+

22.4/1000L of 0.1000 M Sn2+ = 22.4 X 0.10/1000 = 0.00224 mole

so there are 0.00224 X 2= 0.00448 moles Fe3+

iron atomic mass is 56

56 X 0.00448 = 0.251 gm Fe3+

so the mass % of the Fe3+ in the 0.645 gm iron ore sample is

(0.251/0.645) X 100 = 38.9%

Explain how food is transformed to energy for our bodies. ​

Answers

When the stomach digests food, the carbohydrate (sugars and starches) in the food breaks down into another type of sugar, called glucose.
Through the process of cellular respiration, the energy in food is converted into energy that can be used by the body's cells. During cellular respiration, glucose and oxygen are converted into carbon dioxide and water, and the energy is transferred to ATP. Hope it helps

what is the mass of the ice (in kg) composing the iceberg?

Answers

Answer:

picture pls

Explanation:

What are the 4 properties of substances that contain Hydrogen Bonds?

Answers

Answer:

Increase in the melting point, boiling point, solubility, and viscosity of many compounds can be explained by the concept of hydrogen bonding

Explanation:

melting point- when does the solid melt to a liquid

boiling point - a temperature when a liquid will turn into a gas

solubility -solubility is ability of a substance, the solute, to form a solution with another substance

viscosity- Viscosity is a measure of a fluid's resistance to flow. It describes the internal friction of a moving fluid. ( basically how thick it is)

Answer:

Melting point, boiling point, solubillity and viscosity of many substances

Hope this helped you

What makes a charged object attract an uncharged object?

A. The charge in both objects move around.
B. The charged object is positively charged.
C The charges move in the uncharged object.
D The uncharged object becomes negatively charged

Answers

Answer:

C

Explanation:

When we put a charged object near an uncharged object, it produces opposite charges in the near end of the uncharged object by electric induction. ... If we bring it near an uncharged sphere, the sphere forms negative charge near the glass rod, and positive charged on the end away from glass rod

the natural enzyme reaction in food slowly breaks it down and eventually causes it to spoil. what 2 things halt this enzyme reaction and help preserve the food?
microwaving
cooking at high temperature
storing properly in the refrigerator
blanching and canning

Answers

The two processes that help to preserve food are; storing properly in the refrigerator  as well as blanching and canning.

Enzymes are biological catalysts that promote several reactions in the body. The spoilage of food is affected by the enzymes present in food. They act slowly, causing the food to spoil.  

However, there are two way to protect a food from spoilage. These are;

storing properly in the refrigerator blanching and canning

These processes slow down the action of these enzymes that are responsible for the spoilage of food thereby enabling the food to last longer.

Learn more: https://brainly.com/question/2510654

pls help me pls cuz i need a good grade

Answers

Independent variable is the one you change so…
C is the answer

what are sources of error for a simple distillation lab? ​

Answers

Answer:

the fractions obtained are not of acceptable purity

Explanation:

answer this step by step pls

Answers

Answer:

neutrons = mass number - atomic number

. = 39-19 =20

1. Hydrogen and nitrogen combine to form ammonia. When nitrogen and hydrogen bond, nitrogen pulls the electrons from hydrogen toward itself. Which statement about the reactants is correct?

A) Hydrogen is oxidized, and nitrogen loses electrons.
B) Hydrogen is oxidized, and nitrogen is reduced.
C) Hydrogen gains electrons, and nitrogen is reduced.
D) Hydrogen is reduced, and nitrogen is oxidized.

2. Which phrase best defines a redox reaction?

A) A reaction in which the number of oxygen atoms is reduced.
B) A reaction in which elements are transferred between different atoms.
C) A reaction is which oxygen combines with different atoms.
D) a reaction in which elements are released from the system.

3.Which statement describes the process of oxidation?

A) Oxidation results in a loss of electrons, so the oxidation number increases.
B) Oxidation results in a gain of electrons, so the oxidation number increases.
C) Oxidation results in a gain of electrons, so the oxidation number decreases.
D) Oxidation results in a loss of electrons, so the oxidation number decreases.

4. Which chemical equation represents a redox reaction?
A) TiCl4(s) + 2H2O(g) → TiO2(s) +4HCl(g)
B) CaO(s) + SiO2(s) → CaSiO3(l)
C) CaCO3(s) → CaO(s) + CO2(g)
D)Fe2O3(s) + 2Al(s) → Al2O3(s) +2Fe(l)

5. Which elements are oxidized and reduced in the reaction below?
Br2 (l) + 2NaI(aq) → I2 (s) + 2NaBr(aq)

A) Bromine (Br) is oxidized, and iodine (I) is reduced.
B) Iodine (I) is oxidized, and bromine (Br) is reduced.
C) Sodium (Na) is oxidized, and bromine (Br) is reduced.
D) Bromine (Br) is oxidized, and sodium (Na) is reduced.

Answers

Answer:

1. Hydrogen is oxidized, and nitrogen is reduced.

2. a reaction in which electrons are transferred between different atoms

3. Oxidation results in a loss of electrons, so the oxidation number increases.

4. Fe2O3(s) + 2Al(s) → Al2O3(s) + 2Fe(l)

5. Iodine (I) is oxidized, and bromine (Br) is reduced.

Explanation:

Just took the test and made a 100

Answer:

OXIDATION UNIT TEST

1. Which statement best explains why magnesium and chlorine combine in a 1:2 ratio?

A. Magnesium has two valence electrons, and chlorine can accept one electron in its outer shell

2. Hydrogen and nitrogen combine to form ammonia. When nitrogen and hydrogen bond, nitrogen pulls the electrons from hydrogen toward itself. Which statement about the reactants is correct?

C. Hydrogen is oxidized, and nitrogen is reduced.

3. C3H8 + 5O2 → 3CO2 + 4H2O + energy

Which type of reaction is shown?

C. combustion

4. Which phrase best defines a redox reaction?

D. a reaction in which electrons are transferred between different atoms

5. Which statement describes the process of oxidation?

D. Oxidation results in a loss of electrons, so the oxidation number increases.

6. Which chemical equation represents a redox reaction?

D. Fe2O3(s) + 2Al(s) → Al2O3(s) + 2Fe(l)

7. Which statement correctly describes the oxidation number of the manganese atom (Mn) in MnI2 and MnO2?

A. Manganese has an oxidation number of +2 in MnI2 and +4 in MnO2.

8. Br2(l) + 2NaI(aq) → I2(s) + 2NaBr(aq)

Which elements are oxidized and reduced in the reaction?

D. Iodine (I) is oxidized, and bromine (Br) is reduced.

9. Which action occurs at an electrode of a galvanic cell?

D. electron transfer

10. Which statement best compares a battery and a galvanic cell?

A. A battery’s source of power is a galvanic cell in which a redox reaction produces electrical energy.

11. Zn + 2H+ → Zn2+ + H2

2Al + 3Cu2+ → 2Al3+ + 3Cu

Which elements are oxidized?

A. zinc (Zn) and aluminum (Al)

12. 2Cr(s) + 3Cu2+(aq) → 2Cr3+(aq) + 3Cu(s)

Which half reaction occurs at the cathode?

B. 3Cu2+(aq) + 6e– → 3Cu(s)

13. Written

14. Written

15. Written

I hope this helps!

Explanation:

I took the test shhh

Write a Claim based in this question: What happens in the atmosphere and how
is it related to the water cycle.

Answers

Answer:

The atmosphere is the superhighway in the sky that moves water everywhere over the Earth. Water at the Earth's surface evaporates into water vapor which rises up into the sky to become part of a cloud which will float off with the winds, eventually releasing water back to Earth as precipitation.

Explanation:

If you don't want to plagiarize change it up a bit.

Write the balanced chemical equation for the following reaction. Also, classify the
reaction as sythesis, decomposition, single replacement, double replacement, or combustion.
aluminum sulfate + barium chloride —> aluminum chloride + barium sulfate

Answers

Answer:

Explanation:

Al2(SO4)3 + 3BaCl2 ====> 2AlCl3 + 3BaSO4

Sorry forgot to say that it is a double replacement. The Ba goes where there Aluminum is and the Aluminum goes where the Barium is.

The internal balance numbers come from the fact that the ions and complex ions have different valance numbers.

How much heat is required to change 235 g of iodine at 25 degrees celsius into vapor at 198 degrees celsius? The melting point is 113.5 degrees celsius and the boiling point is 185.4 degrees celsius.​

Answers

Answer:

koe Pgl smjega but kya karu mods ka acc mil nai raha and acc delete karna h

Which objects are scratched?

Answers

Answer:

We would need a picture to help you out with this.

Explanation:

germanium has a cubic closest packed structure as a solid. assuming that germanium has an atomic radius of 159 pm, calculate the density of solid germanium.

Answers

Answer:   Germanium has a cubic closest packed structure as a solid. Assuming that germanium has an atomic radius of 159 pm, calculate the density of solid germanium. __________ g/cm3 b.) Germanium has a face-centered cubic unit cell. The density of germanium is 5.32 g/cm3. Calculate a value for the atomic radius of germanium. ___________pm c.) You are given a small bar of an unknown metal X. You find the density of the metal to be 12.0 g/cm3. An X-ray diffraction experiment measures the edge of the face-centered cubic unit cell as 3.89 â„« (1 â„« = 1 ✕ 10−10 m). Identify X.

Explanation:

The density of Germanium is equal to 5.30g/cm^3

Data Given;

atomic radius = 159pm

For a cubic closest packed = 4r

[tex]4r = \sqrt{2a} \\ a = \frac{4}{\sqrt{2} }r\\ a = \frac{4}{2}*159*10^-^1^0\\ a = 4.50*10^-^8cm[/tex]

Density of the cube

The density of the cube is given as the ratio between the mass and volume. But in this case, we have a formula

[tex]d = \frac{Zm}{Na^3}\\ d = \frac{4*72.64}{6.023*10^2^3*9.09*10^-^2^3}\\ d = 5.30 g/cm^3[/tex]

NB;

Z = number of facem = molar massN = Avogadro's constanta = side length

The density of the cube is equal to 5.30g/cm^3

Learn more about structure of an atom;

https://brainly.com/question/8437294


Which two statements are true for both compounds and mixtures?
A. They are made up of more than one type of atom.
B. Their particles all have the same chemical formula.
O C. They can be separated into two or more elements.
D. Their particles are held together by chemical bonds.

Answers

Answer:

B and C is your best option

BRAINLIST ???

the electron pair geometry around the central iodine in I3- is​

Answers

The electron pair geometry around the central iodine in I3- is​ trigonal bipyramidal.

The shapes of molecules is determined by the Valence Shell Electron Pair Repulsion theory (VSEPR). According to this theory, The shape of a molecule depends on the number of electron pairs that surround the valence shell of the central atom in the molecule.

In the structure I3-, the iodine is sp3d hybridized and has a bond angle of 180°. There are three iodine atoms. The central iodine atom is surrounded by two bond pairs and three lone pairs. The  electron pair geometry around the central iodine in I3- is​ trigonal bipyramidal.

Learn more: https://brainly.com/question/8646601

What is the best cream to get rid of self harm scars?

Answers

Mederma Advanced Scar Gel is the most effectively scientific proven method to do so.

not cream, but it I know that coconut oil and honey heals scars in general! I fell once and it was a terrible scar and i places coconut oil at night and the day a little honey and within a few days the scar was unnoticeable. it's sure it will help the same. Remember you are loved and you have so much worth. I am so proud of how far you have come I'm life. <33

how spectral lines are formed

Answers

=Spectral lines are produced by transitions of electrons within atoms or ions. As the electrons move closer to or farther from the nucleus of an atom (or of an ion), energy in the form of light (or other radiation) is emitted or absorbed.…

Answer:

Spectral lines are produced by transitions of electrons within atoms or ions

Which describes a molecule? (Select all that apply.)
It can be two or more different elements combined.
It can be two or more of the same elements combined together.
It can be one element by itself.
It can be the combination of different neutrons.

Answers

Answer:

All of them

Explanation: A molecule can be all of them

In an ionic compound, the total positive charge of all the positive ions ____ the total negative charge of all the negative ions.

Answers

Answer:

I think it would be 0 since cations and anions must always combine in such a way so that their charges cancel.

You want to build a deck off your kitchen and you estimate that you will need 3000 #8 nails all together. Rather than pay extra for them to be put in little boxes, you go to a hardware store where they sell nails in bulk. How does the sales clerk count out 3000 #8 nails for you?

Answers

Answer:

The sales clerk can count your nails in 6 groups of 500 nails, or 30 groups of 100 nails to ease the counting process and garauntee a more accurate result.

Explanation:

A student heated a mixture of iron filings and sulfur strongly. He saw a red glow spread through the mixture as the reaction continued. At the end of the experiment a black solid had been formed.

a) Explain what the red glow indicates.

b) Give the chemical name of the black solid.

c) Write a word equation that and a balanced chemical equation to represent the reaction which has taken place.

d) The black solid is a compound. Explain the difference between the mixture of sulfur and iron and the compound formed by the chemical reaction between them.


Please answer part a, b, c, and d.
If you don't know the answer to all parts but you know the answer to one part then please answer it will still help ​

Answers

Answer:

the answer is c or a am I right☺

The temprature at which a solid melts is the same as the temprature at which its luqid form solidifies.TRUE OR FALSE.PLS GUYS HELP ME!​

Answers

Answer:

The statement is true

Explanation:

The temperature at which a solid melts is the same as the temperature at which its liquid solidifies

its answer is true cause the temprature of melting ice is same as the liquid solidifies

Consider this reaction: 2H CO32- → H2O CO2. Identify each of the following as a product, a reactant, or a coefficient. CO32-: H2O: CO2: The 2 in front of H :.

Answers

Answer:

The 2 in front of the H is a coefficient.

H and (CO3)2 are reactants.

H2O and CO2 are products.

This reaction is an example of Combustion.

Answer:

CO32-:   reactant

H2O:   product

CO2:   product

The 2 in front of H+:  coefficient

Explanation:

This is the real answer, I got it right on edge or whoever you write it.

Describe how you would crystalize potassium nitrate from it's aqueous solution

Answers

Answer:

Potassium nitrate crystals are among the safest and easiest crystals to grow. Potassium nitrate (KNO3) is also known as saltpeter. It’s used in processed meats, fertilizers, gunpowder, fireworks, and many science projects. Here’s how to make potassium nitrate crystals and a look at how to up your game to grow a big crystal.

Materials

It’s fine to do this project in your kitchen. All you need is:

Potassium nitrateWaterCooking pot or microwave-safe bowl

Explanation:

Thanks

Antoine Lavoisier was able to show that mass wasn't lost or destroyed during chemical reactions by weighing all of the matter in the system before and after reactions occurred. What questions would you ask Lavoisier about how he conducted his investigations?​

Answers

Answer: we can ask simple qs like was it a fair experiment and what he was actually looking for. Other qs include his variables use and that how he has maintained the experiment. Finally we could ask him for his outcome and what it would ahve changed in the near future

Explanation:

Other Questions
Refer to You Should Meet Katherine Johnson for a complete version of this text.Part AWhich statement is a main idea of Chapter 4?Katherine has concerns that her calculations might be incorrect and cause problems for the return flight of Apollo 11.Katherine plays an important role in the Apollo 11 flight to the moon that places America ahead in the space race.Katherine believes in teamwork and makes sure others are given credit for their contributions.In Katherine's early years at NASA, a Soviet astronaut becomes the first person to orbit the Earth.Question 2Part B the temperature of a room is 77F what would be the temperature in Celsius scale an empty bottle weight 22.4 g when empty,406g when filled with water and 52.8g when filled with liquid x how spectral lines are formed Find the length of the hypotenuse, side c, of a right triangle with legs of length a = 4 and b = 5. Use a calculator to estimate thesquare root to one decimal place. Which of the following factors help cultural groups preserve their native languages? Globalization Cultural diffusion Geographic barriers Assimilation Immigration please help :( ill give 40 points IF she passes the exam,she [be]very happy if h(x)=5x+2 and g(x) =9x-4 find (h o g) (3) why does jupiter have three distinct layers of clouds? BRAINLIEST AND 50 POINTS!!Based on information from the cladogram and the data table shown below, which of the following best describes the evolutionary history of rabbits? Claws/Nails Feathers Jaws Lungs Mammary glandsBird X X X X Hagfish Lizard X X X Rabbit X X X XSalamander X X Tiger X X X XTrout X Image depicts a cladogram with hagfish, trout, salamander, lizard, bird, rabbit, and tiger represented. Trout diverge from hagfish with the introduction of jaws. Salamander diverges from trout with the introduction of lungs. Lizard diverges from salamander with the introduction of claws and nails. Bird diverges from lizard with the introduction of feathers. Rabbit and tiger diverge from lizard with the introduction of mammary glands. They are more closely related to tigers than they are to birds. They became able to produce mammary glands as a result of lacking feathers. They evolved into a separate species due to the presence of mammary glands. They share a more recent common evolutionary ancestor with salamanders than they do with lizards. aQuestion 2 (20 points)The features of Rococo are...A) Tympanum; Dark InteriorB) Dramatic Irony; Asymmetrical ArchitectureC) Eroticism; Diagonal Line OrientationD) Factual; Shows an Accurate Record Briefly explain 2 functions of an offcice what happens if u fail a semester by not passing 3 classes in high school is my life over Which of the following correctly describes the law of conservation of matter?O Matter makes up 98% of stuff in the universe, so it has to be created and destroyed sometimesO Matter can be destroyed during a chemical reaction as long as it is created again in a different reactionO Matter can only be created, but not destroyed in chemical equationsO Matter can neither be created nor destroyed during a chemical reaction help plz and thank you How would the people involved in the Columbian Exchange have different perspectives on the events? saving on real estate expenses and leveraging knowledge of many different markets are benefits of Which is required forconduction?A.moving fluidsB. Two substances in direct contact with one anotherC. Two substances in close proximity, but not necessarily touching Turn into a equivalent form 6x+13x+5