What elements make up water?

Answers

Answer 1
Water molecules are made of hydrogen atoms and one oxygen atom.

Hope this helped!
Answer 2

Answer:

1 oxygen and 2 hydrogen


Related Questions

Unit Test Unit Test Active 13 TIME REMAINING 01:31:26 Chemical A and Chemical B react in an exothermic reaction. What can be known about what will happen when Chemical A and Chemical B are mixed together? O The new substance will need more energy to form its chemical bonds than the old substance will release. More energy will be released from the old substance than the new substance will need to form its chemical bonds. The color will change as a result of the reaction. O The substance will bubble as a result of the reaction. Save and Exit Next Submit Mark this and return​

Answers

Answer:

More energy is released from the old substance than the new substance needs to form its chemical bonds

Explanation:

Chemical A and Chemical B react in an exothermic reaction. When Chemical A and Chemical B are mixed together more energy will be released from the old substance than the new substance will need to form its chemical bonds. Therefore, option B is correct.

What is an exothermic reaction ?

When a chemical reaction goes on, energy is shifted to or from the surroundings. When energy is moved to the surroundings, this is called an exothermic reaction, and the temperature of the surroundings increases.

Examples of exothermic reactions are combustion reactions and many oxidation reactions.

A chemical reaction is exothermic if heat is passed by the system into the surroundings. Because the surroundings are deriving heat from the system, the temperature of the surroundings increases.

Thus, option B is correct.

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A gas has a density of 1.57 g/L at 40.0 °C and 2.00 atm of pressure. What is the identity of the gas?

Answers

Answer:

Ne is the identity of the gas

Which of these results in kinetic energy of an object?

Answers

Answer: B

Kinetic Energy is the energy possessed by the body due to "motion".

Answer:

B- motion

Explanation:

Correct on edge 2021

️️

Please Help!!
Nitrogen gas can be prepared by passing ammonia over copper(II) oxide, and the other products are copper metal and water vapor. If a sample containing 3.58 moles of NH₃ is reacted with excess copper(II) oxide, how many grams of N₂ will be formed?

Answers

Mass of N₂ will be formed : 50.12 g

Further explanation

Reaction

2 NH₃(g) + 3 CuO(s) → N₂(g) + 3 Cu(s) + 3 H₂O(g)

moles NH₃ = 3.58

ratio mol NH₃ : mol N₂ = 2 : 1

so mol N₂ :

[tex]\tt \dfrac{1}{2}\times 3.58=1.79[/tex]

mass N₂ (MW=28 g/mol) :

[tex]\tt 1.79\times 28=50.12~g[/tex]

Show by calculation which process produces more energy per gram of material reacting

Answers

The answer is meaw meaw

What color change is exhibited by phenolphthalein during a titration of aqueous acetic acid with aqueous sodium hydroxide ? a. colorless to pink b. pink to colorless c. no color change d. yellow to blue e blue to yellow

Answers

phenolphthalein during a titration

The color change exhibited by phenolphthalein during a titration of aqueous acetic acid with aqueous sodium hydroxide is pink to colorless.

An indicator is an organic dye which changes color in acidic, basic and neutral medium.

Phenolphthalein is an example of an indicator. When aqueous acetic acid is titrated against aqueous sodium hydroxide, the indicator may be added to the basic solution.

Phenolphthalein has a pink color in a basic medium. As the acid is added gradually, the solution turns colorless at end point.

Hence, the color change exhibited by phenolphthalein during a titration of aqueous acetic acid with aqueous sodium hydroxide is pink to colorless.

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Does a reaction occur when aqueous solutions of ammonium carbonate and chromium(III) nitrate are combined? yesno If a reaction does occur, write the net ionic equation. Use the solubility rules provided in the OWL Preparation Page to determine the solubility of compounds. Use the pull-down boxes to specify states such as (aq) or (s). If a box is not needed leave it blank.

Answers

Answer:

3 CO₃²⁻(aq) + 2 Cr³⁺(aq) ⇒ Cr₂(CO₃)₃(s)

Explanation:

Let's consider the molecular equation that occurs when aqueous solutions of ammonium carbonate and chromium(III) nitrate are combined.

3 (NH₄)₂CO₃(aq) + 2 Cr(NO₃)₃(aq) ⇒ 6 NH₄NO₃(aq) + Cr₂(CO₃)₃(s)

The complete ionic equation includes all the ions and insoluble species.

6 NH₄⁺(aq) + 3 CO₃²⁻(aq) + 2 Cr³⁺(aq) + 6 NO₃⁻(aq) ⇒ 6 NH₄⁺(aq) + 6 NO₃⁻(aq) + Cr₂(CO₃)₃(s)

The net ionic equation includes only the ions that participate in the reaction and the insoluble species.

3 CO₃²⁻(aq) + 2 Cr³⁺(aq) ⇒ Cr₂(CO₃)₃(s)

Write the condensed electron configurations for the follow- ing atoms and indicate how many unpaired electrons each has: (a) Mg, (b) Ge, (c) Br, (d) V, (e) Y, (f) Lu.

Answers

Answer:

i think it is ge

Explanation:

Two or more than two atoms with different physical or chemical properties can not combine together to form an element. Therefore, the condensed electron configurations for the given element can be written as below.

What is element?

Element generally consist of atoms or we can atoms combine to form element. Atoms of an element is always same, means all the properties of all atoms of one type of element is same.

The systematic distribution of electrons in the various atomic orbitals is called its electronic configuration. 1,2,3 represents the number of shells and s and represents the orbitals. The superscripts represents the number of electrons in each orbitals.

Electronic configuration of Mg   Ne 3s²

Electronic configuration of Ge   [Ar] 3d¹⁰ 4s² 4p²

Electronic configuration of Br    [Ar] 3d10 4s² 4p⁵

Electronic configuration of V     [Ar] 3d³ 4s²

Electronic configuration of  Y   [ Kr ]4d¹ 5s²

Electronic configuration of Lu     [Xe] 4f¹⁴ 5d¹6s²

Therefore, the condensed  electron configurations for the given element can be written as above.

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A solution of acetic acid is prepared in water by adding 11.1 g of sodium acetate to a volumetric flask and bringing the volume to 1.0 L with water. The final pH is measured to be 5.25. What are the concentrations of acetate and acetic acid in solution? (Assume that the temperature of the solution is 25 degrees Celsius)

Answers

Answer:

Molarity acetate: 0.1353M

Molarity acetic acid: 0.0418M

Explanation:

When in solution you have a weak acid (Acetic acid) and its conjugate base (sodium acetate) a buffer is produced. The pH of this buffer is obtained using the H-H equation:

pH = pKa + log [A⁻] / [HA]

Where pH is pH of the solution = 5.25

pKa is pKa of acetic buffer = 4.74

[A⁻] is molarity of acetate ion - Molar mass sodium acetate: 82.03g/mol-:

11.1g * (1mol / 82.03g) = 0.1353moles A⁻ / 1.0L = 0.1353M

And [HA] are moles of acetic acid.

Solving for HA:

5.25 = 4.74 + log [0.1353] / [HA]

0.51 =  log [0.1353] / [HA]

3.236 = [0.1353] / [HA]

[HA] = 0.1353M / 3.236

[HA] = 0.0418M

What is the Dependent variable?

Answers

Explanation:

Just like an independent variable, a dependent variable is exactly what it sounds like. It is something that depends on other factors. For example, a test score could be a dependent variable because it could change depending on several factors such as how much you studied, how much sleep you got the night before you took the test, or even how hungry you were when you took it. Usually when you are looking for a relationship between two things you are trying to find out what makes the dependent variable change the way it does.

if you are correct i will be sure to give your brainliest

Answers

Answer:

slow down speed updon't change1 will be the right answer

Answer:

Speeds up

Explanation:

In substitution reactions, (CH3)3C-I reacts at the same rate with Br- and Cl- even though Br- is a more reactive nucleophile than Cl-. Why?A. (CH3)3C-Br reacts by SN1 mechanism whose rate is independent of nucleophile reactivity. B. (CH3)3C-Br reacts by SN2 mechanism and therefore all nucleophiles react at the same rate regardless of their reactivity. C. The t-butyl carbocation is so reactive, the measurable rate of it's reaction with different nucleophiles is imperceptible. D. The t-butyl group sterically hinders nucleophiles, making different nucleophiles appear to react at the same rate.

Answers

Answer:

A. (CH3)3C-I reacts by SN1 mechanism whose rate is independent of nucleophile reactivity.

Explanation:

We must recall that (CH3)3C-I is a tertiary alkyl halide. Tertiary alkyl halides preferentially undergo substitution reaction via SN1 mechanism.

In SN1 mechanism, the rate of reaction depends solely on the concentration of the alkyl halide (unimolecular mechanism) and is independent of the concentration of the nucleophile. As a result of this, both Br^- and Cl^- react at the same rate.

Write the expression for the equilibrium constant Kp for the following reaction. (Enclose pressures in parentheses and do NOT write the chemical formula as a subscript. For example, enter (PNH3)2 as (P NH3)2. If either the numerator or denominator is 1, please enter 1.) PCl5(g) ↔ PCl3(g) Cl2(g)

Answers

Answer and Explanation:

For the following balanced reaction:

PCl₅(g) ↔ PCl₃(g) + Cl₂(g)

We can see that all reactants and products are gases, so it is an homogeneous equilibrium. The expression for the equilibrium constant Kp can be written from the partial pressures (P) of reactants and products as follows:

[tex]Kp=\frac{(P PCl_{3})(P Cl_{2})}{(P PCl_{5})}[/tex]

Where PPCl₃ is the partial pressure of PCl₃ (reactant), PCl₂ is the partial pressure of Cl₂ (reactant) and PPCl₅ is the partial pressure of PCl₅ (product).

QUESTION 24
Calculate [H 30+] of a solution with a pH of 2.14.

Answers

Answer:

The hydronium ion concentration can be found from the pH by the reverse of the mathematical operation employed to find the pH. [H3O+] = 10-pH or [H3O+] = antilog (- pH).

I hope what I just explained is enough .

Answer the questions about the characteristics of the elements in group 2 (the alkaline earth metals).1. What happens when the elements in group 2 react with iodine? a. a salt is formed (MI_2) b. a salt is formed (MI) c. no reaction 2. How do they react with water? a. hydrogen gas is released b. oxygen is released 3. How do they react with oxygen? a. an oxide is formed (M_2 O) b. an oxide is formed (MO) c. no reaction 4. Which reacts the most vigorously? a. Ba b. Mg c. Ca d. Sr e. Ba 5. Which element in the group is the most metallic in character? a. Be b. Mg c. Ca d. Sr e. Ba

Answers

Answer:

Explanation:

1

When elements in group 2 react with Iodine, a salt MI_2 is formed

2

When they react with water, Hydrogen gas is released

3

When they react with Oxygen, an Oxide, MO is formed

4

The most vigorously reactive metal in group 2 is Barium, Ba. Reactivity increases as one moves downward in group 2

5

The most metallic element is Barium, Ba. This is because in the periodic table, metallic strength of metals increases as one moves down the table.

The thing that happens when the elements in group 2 react with iodine is:

A salt MI_2 is formed

The way these elements react with water is:

They form hydrogen gas  

The way they react with oxygen is:

They produce an Oxide, MO

The element which reacts the most vigorously  in group 2 is:

Barium, Ba. This is because their reactivity increases as one moves downward in group 2

The element in the group which is the most metallic in character is:

Barium, Ba. It is this way because of the changes in metallic strength as metals change positions in the table

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what is filtration??​

Answers

Answer:

the action or process of filtering something.

Explanation:

Filtration is a physical, biological or chemical operation that separates solid matter and fluid from a mixture with a filter medium that has a complex structure through which only the fluid can pass.

A mixture of Xe, Kr and Ar has a total pressure of 6.70 atm. What is the mole fraction of Kr if the partial pressure of Xe is 1.60 atm and that of Ar is 2.80 atm.

Answers

Answer:

0.343

Explanation:

Step 1: Given data

Total pressure of the gaseous mixture (P): 6.70 atmPartial pressure of Xe (pXe): 1.60 atmPartial pressure of Ar (pAr): 2.80 atm

Step 2: Calculate the partial pressure of Kr

The total pressure of the mixture is equal to the sum of the partial pressures of the individual gases.

P = pXe + pAr + pKr

pKr = P - pXe - pAr

pKr = 6.70 atm - 1.60 atm - 2.80 atm

pKr = 2.30 atm

Step 3: Calculate the mole fraction of Kr

We will use the following expression.

X(Kr) = pKr/P

X(Kr) = 2.30 atm/6.70 atm

X(Kr) = 0.343

Considering the Dalton's partial pressure, the mole fraction of Kr is 0.34.

The pressure exerted by a particular gas in a mixture is known as its partial pressure.

So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:

[tex]P_{T} =P_{1} +P_{2} +...+P_{n}[/tex] where n is the number of gases.

This relationship is due to the assumption that there are no attractive forces between the gases.

Dalton's partial pressure law can also be expressed in terms of the mole fraction of the gas in the mixture.

So in a mixture of two or more gases, the partial pressure of gas A can be expressed as:

[tex]P_{A} =x_{A} P_{T}[/tex]

In this case, you know:

Total pressure= 6.70 atm. Partial pressure of Xe is 1.60 atm. Partial pressure of Ar is 2.80 atm.

So, replacing in the Dalton's partial pressure law:

[tex]P_{T} =P_{Xe} +P_{Ar} +P_{Kr}[/tex]

6.70 atm= 1.60 atm + 2.80 atm + [tex]P_{Kr}[/tex]

6.70 atm- 1.60 atm- 2.80 atm= [tex]P_{Kr}[/tex]

2.30 atm=[tex]P_{Kr}[/tex]

Then: [tex]P_{Kr} =x_{Kr} P_{T}[/tex]

2.30 atm= [tex]x_{Kr}[/tex] 6.70 atm

[tex]x_{Kr}[/tex] =2.30 atm ÷6.70 atm

[tex]x_{Kr}[/tex] = 0.34  

In summary, the mole fraction of Kr is 0.34.

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What is the change in the internal energy of a system that does 100 joules of
work and absorbs 1,000 joules of heat?

Answers

Answer:900j

Explanation:

Roughly how many water molecules are ionized at any given time in a sample of room-temperature water? a. one in a thousand b. one in a million c. one in a billion d. one in a trillion

Answers

Answer:

one in a billion

Explanation:

We have it known that Pure water is entirely made up of H2O molecules. Just 1 in 10⁹, that is a billion molecules are ionized when it is at room temperature.

The Ionization of water has this chemical equation:

H2O <--> H+ + OH-

When At equilibrium and at room temperature, we have the rate of forward reaction and the backward reaction to be very fast such that no water molecule would eventually remain ionized.

Therefore our answer is roughly one in a billion water.

Heat is a form of energy transfer from a blank location

Answers

Heat is a form of energy and transfer of it takes place from hotter body to cooler body.

What is heat transfer?

Heat transfer is a process in which heat transfers from one object to another object without any loss.

Heat transfer is a branch of thermal engineering that deals with the production, use, conversion, and transfer of thermal energy between physical systems.

Transfer of heat generally takes place from hotter body to the cooler body till when both the bodies gain the same temperature.

Hence heat transfers from hotter body to cooler body.

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Are transition metals reactive?

Answers

Answer: Yes

Explanation:

Please help me on question #2 please please really need help due today at 9:00pm please

Answers

No, the biggest star in the universe is UY scuti

I need help click the image please help

Answers

Answer:

Answer:

a plant cell

Explanation:

because the chrolopast is green

Explanation:

Why is the following electron configuration not possible?
1-9-1

Answers

Answer: because its noy

Explanation:

Which of the compounds of H3PO4, Mg(OH)2, LiOH, and HCl, behave as acids when they are dissolved in water?A. Mg(OH)2 and LiOH.B. B H3PO4 and HC.C. Only HCl.D. Only LiOH.

Answers

Answer:

B. H3PO

Explanation:

The pH, texture, reactivity, and conductivity should be seen while determining acid or base. Among given option, H₃PO₄ is the acid  when dissolved in water.

What are acid and base?

Acid is a substance that has sour taste, pH lies in the range of 0-7 and give hydronium ion when dissolved in water. Acid turns blue litmus red. Whereas base has bitter, its pH is between 7-14 and it turns red litmus blue. It give hydroxide ion when dissolved in water.

Extensive properties, such as mass and volume depend on the amount of substance present and are not useful in the identification of a substance. Measuring mass and volume is not useful While determining acid or base. Out of given compounds, H₃PO₄ is the acid  when dissolved in water.

Therefore, H₃PO₄ is the acid  when dissolved in water.

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If 15.5 mL of 0.225 M aqueous magnesium chloride is added to 37.5 mL of 0.250 M aqueous lead(II) nitrate, then what mass of lead(II) chloride precipitates?A. 0.485 g.B. 0.971 g.C. 1.94 g.D. 3.888 g.E. 5.82 8 g.

Answers

Answer:

B. 0.971 g

Explanation:

When MgCl₂(aq) reacts with Pb(NO₃)₂(aq), PbCl₂(s) and Mg(NO₃)₂(aq) are produced:

MgCl₂(aq) + Pb(NO₃)₂(aq) →, PbCl₂(s) + Mg(NO₃)₂(aq)

Thus, we need to find imiting reactant finding moles of each reactant:

Moles MgCl₂:

15.5mL = 0.0155L * (0.225 mol / L) = 3.49x10⁻³ moles

Moles Pb(NO₃)₂:

37.5mL = 0.0375L * (0.250mol / L) = 9.38x10⁻³ moles

As the ratio of the reactants is 1:1, the moles of PbCl₂ are 3.48x10⁻³ moles.

We need to convert thes moles to mass using molar mass of PbCl₂ (278.1g/mol), thus:

3.48x10⁻³ moles * (278.1g/mol) =

0.968g of PbCl₂ are precipitate

Thus, right answer is:

B. 0.971 g

Explain why water can take many different paths while moving though the water cycle

Answers

Answer:

the water cycle shows the continuous movement of water within the Earth and atmosphere. it is a complex system that includes many different processes. Beckley water evaporates into water vapor, condenses to form clouds, and precipitates back to Earth in the form of rain and snow. Water in different phases moved across the atmosphere. The Cove water flows across the land, into the ground, threw the ground. Groundwater moves into plants and evaporates from plants into the atmosphere. Solid ice and snow can turn directly into gas. It can also take place when water vapor becomes solid

Explanation:

hope this helps :]

Water can take different paths while moving through water   cycle because of it's unique property to exist in different phases.

What is water cycle?

Water cycle is one of the biogeochemical cycles which describes the movement of water above and below the surface of earth. Mass of water remains constant but it's mass in different forms varies as it exists in form of  glaciers, water and water vapor.

Water gets converted from one form to another by processes such as evaporation,transpiration, condensation,precipitation and surface run off.During this , water changes it's phases from liquid to vapor and solid . Ocean plays a major role in water cycle as it is a source of 86% global evaporation of water.

It involves change in energy leading to changes in temperature. When it evaporates,it takes energy from surroundings and while condensing, it releases energy in to the environment. The evaporation phase purifies the water and then replenishes land with freshwater.

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Would you want to build the wire for a cell phone charger out of nitrogen (N)? Why or why not? Be sure to explain how the properties and structure of nitrogen influence your decision.

Answers

Answer:

No

Explanation:

Nitrogen cannot be used to build the wire for a cell phone charger.

What are the elements used to build charger ?

Inside phone chargers is aluminum. Aluminum is used in phone chargers because it does a better job of conducting electricity than copper does. Bauxite is used to make aluminum. The crust of the earth contains aluminum.A phone charger is also made of tungsten. The wire's resistance is provided by tungsten. Wolframite make up tungsten. The crust of the Earth contains tungsten.Additionally, phone chargers contain gold. Because it is a conductor, gold is used in phone chargers. However, gold is also resistant to oxidation. Copper ores are used to make gold. Gold can be found everywhere on Earth and in its oceans.Silver is within your mobile charger. Silver conducts electricity. Silver is comprised of various minerals. Silver can be found free in nature at times, but it can also be found in copper, gold, and nickel.Phone chargers contain copper. Copper is also used to carry electric current.Chalcopyrite make up copper. Copper ore deposits can be found all over the world.Copper windings in a transformer are used to convert a 220 V input voltage into a 5 V operating output voltage in mobile phone chargers. The output voltage is greater than the input voltage if the secondary coil has more turns than the primary coil.Nitrogen (N), a nonmetallic element in the periodic table's Group 15 [Va] group. It is the most abundant element in Earth's atmosphere and a component of all living matter. It is a colorless, tasteless, and odorless gas. Nitrogen is used to shield motors, prevent oxidation and other chemical reactions, pressurize cable jackets, and more in the electrical industry.

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Larry was told that a certain muscle cream was the newest best thing on the market and claims to double a person’s muscle power when used as part of a muscle-building workout. Interested in this product, he buys the special muscle cream and recruits Patrick and SpongeBob to help him with an experiment. Larry develops a special marshmallow weight-lifting program for Patrick and SpongeBob. He meets with them once every day for a period of 2 weeks and keeps track of their results. Before each session Patrick’s arms and back are lathered in the muscle cream, while Sponge Bob’s arms and back are lathered with the regular lotion.




Which person is the control group?



SpongeBob

SpongeBob


Patrick

Patrick


Larry

Answers

SpongeBobs twin brother and Larry and Patrick’s twin brother

What is the ground-state electron configuration for the Mn4 ion and is it paramagnetic or diamagnetic?

Answers

Answer:

[Ar]3d4 is the ground-state electron configuration for the Mn4 ion

but i don't know whether it is paramagnetic or daimagnetic

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