why aren't hydrogen fuel cells currently available to the public​

Magnesium is a main-group metal element in period number 3 of the periodic table, which is the correct answer.

Period number 3 of the periodic table has eight elements that are arranged in order of increasing atomic number. These elements are sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, and argon.

The period number signifies the highest energy level that the element's electrons occupy.

The metallic character of the elements reduces, and the non-metallic character increases as you move across a period. Magnesium is a silvery-white metal and the eighth most abundant element in the Earth's crust.

Magnesium is used in alloys, pyrotechnics, and flares, and it is also used to manufacture lightweight and durable products like aircraft parts.

Magnesium is a main-group metal element and is located in Group 2 of the periodic table. It is in the same group as beryllium, calcium, strontium, barium, and radium.

It is a highly reactive metal that readily loses its two outermost electrons to form a stable cation with a 2+ charge. Magnesium ions have a high affinity for water molecules, which makes them essential in biological systems as well.

Magnesium is an essential element for human health, and it is involved in many physiological processes, including muscle contraction and relaxation, nerve transmission, and energy metabolism.

Magnesium deficiency can cause a variety of health problems, including muscle weakness, cramps, and irregular heartbeats.

In conclusion, magnesium is a main-group metal element in period number 3 of the periodic table.

To know more about Magnesium, visit:

https://brainly.com/question/8351050

#SPJ11

Answer:

Reduction:

2e- + 2k+ ➡️ 2k

2e- + pb2+ ➡️pb

2e- +2H+ ➡️H2(diatomic molecule)

Oxidation :

2cl- ➡️cl2 + 2e- (Cl is a diatomic molecule)

2O-2➡️ O2+4e- (also diatomic molecule)

2Br-➡️ Br2 + 2e- (Br is also a diatomic molecule)

I don't know if I answered ur question or not but I hope this would help

The following changes affect the value of the equilibrium constant for a gas-phase exothermic reaction:

Addition of a catalyst-  Increase equilibrium constant

Decrease in the temperature - Decrease equilibrium constant

Removal of a product- No effect on equilibrium constant

Decrease in the volume- Decrease equilibrium constant

Removal of a reactant- Decrease equilibrium constant

Define  exothermic process

An exothermic process in thermodynamics is a thermodynamic process or reaction that releases energy from the system to its surroundings, typically in the form of heat but occasionally in the form of light (such as a spark, flame, or flash), electricity (such as from a battery), or sound (such as the explosion produced by the burning of hydrogen).

The relationship between a reaction's products and reactants with regard to a certain unit is expressed by the equilibrium constant, K. The equilibrium constant is temperature-dependent and unaffected by the precise ratios of reactants to products, the presence of a catalyst, or the presence of inert substances. Additionally, it is unaffected by the volumes, pressures, and concentrations of the reactants and products.

To learn more about exothermic process  use:

https://brainly.com/question/3159758

#SPJ4

Answer:

The number of protons, massive, positively charged nuclear particles defines the identity of the nucleus.

Woah. Vocabulary here.

An isotope is any of two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in the nucleus, or different atomic weight. There are 275 isotopes of the 81 stable elements, in addition to over 800 radioactive isotopes, and every element has known isotopic forms. Isotopes of a single element possess almost identical properties.

Helium is usually defined as an inert, gaseous element present in the sun's atmosphere and in natural gas, and also occurring as a radioactive decomposition product, used as a substitute for flammable gases in dirigible balloons. Symbol: He; atomic weight: 4.0026; atomic number: 2; density: 0.1785 g/l at 0 °C and 760 mm pressure.

Explanation:

The number of protons, massive, positively charged nuclear particles, gives Z, the atomic number, which defines the identity of the nucleus.

Z=1, "hydrogen",Z=2, "helium",Z=3, "lithium",...........Z=21, "scandium".

The nucleus may contain various numbers of neutrons, massive, neutrally charged nuclear particles, which gives to the existence of isotopes.

For hydrogen, \(Z=1\) by defintion. That is there is a proton in all hydrogen nuclei. Some hydrogen nuclei contain 1 neutron to give the deuterium isotope, \(^2H\) ; an even smaller number of hydrogen nuclei contain 2 neutrons, to give the tritium isotope, \(^3H\) ; Most atoms have a number of isotopes in different proportions.

To answer your question, the helium atom has \(Z=2\) ; i.e. there are 2 nuclear protons, which is what defines the atom as helium. The most common isotope of helium is \(^4He.^3He\) and \(^5He\) re known with vanishingly small abundances, and half lives.

This video discusses how to determine the number of subatomic particles in C-12 , C-14 , H-1 , H-2 and H-3 .

Thanks.

Answer:

i believe its gas sorry if i am wrong

Explanation:

The final pressure of the N₂ gas is 1121 mmHg when heated from -55 ∘C to 28 ∘C.

To solve this, we will use combined gas law:

(P₁/T₁) = (P₂/T₂)

where P₁ will be the initial pressure, T₁ is the initial temperature, P₂ is the final pressure, and T₂ will be the final temperature.

We will need to convert the temperatures into Kelvin:

T₁ = -55 + 273 = 218 K

T₂ = 28 + 273 = 301 K

Substituting the values, we get:

(815 mmHg/218 K) = (P₂/301 K)

Solving for P₂, we get:

P₂ = (815 mmHg × 301 K)/218 K

P₂ = 1121 mmHg

To know more about final pressure here

https://brainly.com/question/14812539

#SPJ4

Answer:

0.1139952 is the answer

Explanation:

An example in the section discusses disassembling a hydrogen atom.

The hydrogen atom is the simplest and most abundant element in the universe, it consists of one proton and one electron. Disassembling a hydrogen atom refers to the process of separating its electron from the proton, which can be achieved through the application of energy. One method to disassemble a hydrogen atom is through ionization. Ionization occurs when a hydrogen atom absorbs enough energy to cause its electron to become excited and eventually detach from the proton, forming a hydrogen ion. This process plays a significant role in various scientific and industrial applications, including plasma research and nuclear fusion experiments.

Another example of disassembling a hydrogen atom is through chemical reactions. When hydrogen atoms react with other atoms or molecules, they form new chemical compounds by sharing or exchanging electrons, this process effectively disassembles the original hydrogen atom, as its electron becomes part of a new atomic or molecular structure. Understanding the disassembly of a hydrogen atom provides valuable insights into the behavior of matter at the atomic level and contributes to advancements in various fields such as chemistry, physics, and astronomy. So therefore a hydrogen atom is an example in the section discusses disassembling.

Learn more about hydrogen atom at:

https://brainly.com/question/30438922

#SPJ11

Answer: It loses kinetic energy.

Answer:

Radiation is responsible for most of the heat transferred into the room. Heat transfer also occurs through conduction into the room, but at a much slower rate. Heat transfer by convection also occurs through cold air entering the room around windows and hot air leaving the room by rising up the chimney.

When a fluid, such as air or a liquid, is heated and then travels away from the source, it carries the thermal energy along. This type of heat transfer is called convection. The fluid above a hot surface expands, becomes less dense, and rises. ... A space heater is a classic convection example.

Secondary consumers are organisms that primarily feed on herbivores or other primary consumers.

They occupy the next trophic level above the primary consumers in a food web. They obtain energy by consuming the primary consumers and play an important role in regulating the population of herbivores.

Examples of commonly observed secondary consumers include:

Carnivorous mammals: Animals such as wolves, lions, and tigers that feed on herbivores like deer, zebras, or gazelles.

Birds of prey: Species like eagles, hawks, and owls that consume small mammals, reptiles, or other birds.

Carnivorous fish: Fish like pike, barracuda, or bass that prey on smaller fish or aquatic invertebrates.

Predatory insects: Insects such as spiders, mantises, or dragonflies that feed on other insects, including herbivorous insects.

In a specific food web, the identification of secondary consumers would depend on the specific organisms present and their feeding interactions. It would be necessary to analyze the trophic relationships among the organisms in the food web to determine the secondary consumers accurately.

For more such questions on Secondary consumers visit:

https://brainly.com/question/28631974

#SPJ8

Studies on amphibian oocytes showed that MPF or maturation promoting factor is E. all above.

Amphibian oocytes are specialized cells that undergo meiosis to produce eggs. However, research on amphibian oocytes has revealed that MPF is not involved in regulating the cell cycle in these cells. Instead, MPF levels fluctuate depending upon the stage of the cell cycle, and it is produced at a steady rate throughout the process. MPF triggers replication of chromosomes, which is necessary for cell division and the production of eggs.

Interestingly, MPF also inhibits maturation of oocytes until the appropriate time, ensuring that the eggs are properly formed before they are released. In summary, while MPF plays a critical role in cell cycle regulation in many organisms, its function in amphibian oocytes is more nuanced and involves fluctuating levels and timing of action. So the correct answer is E. all above .

Learn more about chromosomes at

https://brainly.com/question/30993611

#SPJ11

Answer:

Convection is a heat transfer mechanism where heat moves from one place to another through fluid currents. Forced convection is simply using this mechanism in a useful way to heat or cool a home efficiently, such as using a fan.

Explanation:

2gcm³ is the density of a glass fragment that has a mass of 1.5g and a volume of 0.75mL.

The term density is define as the ratio of mass and volume. The formula for density is d = M/V, where d is density, M is mass, and V is volume. Density is commonly expressed in units of grams per cubic centimeter.

Density = mass / volume

Given:

Density = ?

Mass = 1.5 gram

Volume = 0.75 ml

By substituting this values in give equation we get,

Density = 1.5 / 0.75

= 2 gcm³

Thus, 2 gcm³ is the density of a glass fragment that has a mass of 1.5g and a volume of 0.75mL.

To learn more about the density, follow the link;

https://brainly.com/question/29775886

#SPJ1

Milk of magnesia helps to neutralize stomach acid because it is a strong base.

Acid: Acids have a sour taste and turn certain dyes red.

It gives off hydrogen ions in water and forms salts by combining with certain metals.

Acids are substances that has pH greater less than 7.

Base: Base turn certain dyes blue.

It takes off hydrogen ions in water and forms salts by combining with certain metals.

It has pH greater than 7.

When acid and base combine, salt is formed.

Milk of magnesia is a laxative that is thought to work by drawing water into the intestines, an effect that helps to cause movement of the intestines.

It is an antacid.

Hence, Milk of magnesia helps to neutralize stomach acid because it is a strong base.

Learn more about Milk of magnesia, click here https://brainly.com/question/22066653

#SPJ4

Explanation:

could you post the text? its inconvenient to go back and forth to the picture.

The time required for a reaction to reach equilibrium can depend on the value of Kc, which represents the equilibrium constant. The equilibrium constant, Kc, is determined by the concentrations of the reactants and products at equilibrium.

In general, reactions with a larger Kc value tend to reach equilibrium more quickly than those with a smaller Kc value. This is because a larger Kc indicates that the concentration of products is higher compared to the concentration of reactants at equilibrium. As a result, the reaction proceeds more rapidly to reach the point where the ratio of products to reactants matches the value of Kc.

Therefore, among the given options, the answer would be option (c) where Kc is a very large number. In this case, the reaction would require the least amount of time to reach equilibrium.

It's important to note that the actual time required for a reaction to reach equilibrium depends on various factors such as temperature, pressure, and the presence of catalysts. Additionally, the time required for a reaction to reach equilibrium cannot be determined solely based on the value of Kc. However, in general, a larger Kc value suggests a quicker attainment of equilibrium.

Learn more about equilibrium here :-

https://brainly.com/question/14281439

#SPJ11

The adjacent nucleotides are bound to each other through a phosphodiester bond in a nucleic acid.

Nucleic acid is a biopolymer made up of nucleotide monomers that make up nucleic acid chains. The nucleotide's three components are a five-carbon sugar, a phosphate group, and a nitrogenous base. Nucleic acids are present in all living cells, including viruses and bacteria, and they play a critical role in storing, transmitting, and expressing genetic information. RNA and DNA are two types of nucleic acids.

The phosphate group in one nucleotide forms a phosphodiester bond with the hydroxyl group on the sugar molecule of the next nucleotide in line in nucleic acids. This reaction is carried out by removing a molecule of water, resulting in a strong covalent bond between two nucleotides. These bonds make up the sugar-phosphate backbone of a nucleic acid chain, which is fundamental to its structure.

Learn more about Nucleic acid: https://brainly.com/question/17701344

#SPJ11

Answer:

Concept of chemi-fluorescence

Explanation:

A glow stick usually consists of two chemicals in a larger plastic tube: , a base catalyst (mostly sodium salicylate), and a suitable dye (sensitizer, or fluorophor). This creates an exergonic reaction when mixed together.

When a glow stick is bent, the flurophor which is a chemical that easily re-emits light upon excitation in smaller capsules is released into the other substance, there by causing it to emit radiation/light in the uv-visible region. The brightness and longevity of the glow stick is determined by varying the concentration of these chemicals.

I hope this explanation clarifies things.

Answer:

Reaction 4

Explanation:

exothermic reaction is reaction in which reaction takes place evolving heat

Answer:

NO

Explanation:

the reson is because nobody wanna answer my questions

The energy required is Ionization energy

Answer:

Solids- slow

Liquids- medium

Gasses- fast

Explanation:

Answer:

Solids move slowly because they are the most condensed. Gases move the quickest, because they are the least condensed, and liquids are in the middle of the two.

Explanation:

I hope this helps! :)

Answer:

It is the temperature at which water is frozen or is pure ice

"Absolutely zero" temperature is the coldest temperature possible. It's so cold that everything stops moving and has no energy left. Scientists use a special scale called Kelvin to measure temperature, and absolute zero is at 0 Kelvin or -273.15 degrees Celsius (-459.67 degrees Fahrenheit). We can't actually reach absolute zero in real life, but scientists have come very close in laboratories using special cooling methods.

Answer:

Static electricity is the result of an imbalance between negative and positive charges in an object. These charges can build up on the surface of an object until they find a way to be released or discharged.

Explanation:

The given reaction is already balanced, that is to say tha the number of atoms in the reactants matches the number of atoms in the products. In the reaction, we can see the relationship between CaC2 and H2O. For each mole of CaC2 two moles of H2O react.

So, if 4.8 moles of CaC2 are consumed the moles of H2O needed will be:

Mol of H2O = Mol of CaC2 x 2

Mol of H2O = 4.8 x 2 = 9.6 mol of H2O

Now, to calculate the grams of H2O we will use the following equation and the mass molar of H2O.

Mass molar of H2O =18.01 g/mol

So, if 4.8 moles of CaC2 are consumed in this reaction, 172.9 g of H2O are needed

They include the folowing;

1. The break-up of firm particles = Endothermic heat absorbing process

2. The break-up of solute fragments = Endothermic heat arresting process

3. The joining of solute and solvent particles = Exothermic heat bearing process

The Enthalpy of Resolution maybe found in this manner including three elements: ΔHsoln = ΔH1 + ΔH2+ ΔH3

1. Break-up of the solute molecules from each one (extending the solute), this is an endothermic response. (ΔH1)

2. Break-up of the financially sound molecules from each one (extending the solid fragments), this is also an endothermic backlash (ΔH2)

In their divided states, the solute and fit fragments are free to attract each one liquid.

3. The exothermic response of the solute and fit resulting in the composition of the resolution. (ΔH3)

read more about energy entering the system

https://brainly.com/question/30279924

#SPJ4

Answer:

Gases have three characteristic properties: (1) they are easy to compress, (2) they expand to fill their containers, and (3) they occupy far more space than the liquids or solids from which they form.

SO the answer is- D. All of the above

Explanation:

1. carbon lies in the 2nd period where silicon in the third period.

2. carbon is a non metal whereas silicon is a metalloid.

3. there are only 3 isotopes of carbon and 23 isotopes of silicon

4. size of silicon atom is larger

5. silicon is heavier than carbon.

According to the question , \(10^{80}\) protons create a galaxy.

1.67262 1027 kg, or 1,836 times the mass of an electron, is the rest mass of the proton, a stable subatomic particle with a positive charge that is equivalent to one electron's charge.

One down quark and two up quarks make up protons. Two down quarks and one up quark make up neutrons. One of the four fundamental forces, the "strong nuclear force," keeps the nucleus together (gravity and electromagnetism are two others).

The amount of protons in the cosmos is measured by the Eddington number , in astrophysics. Eddington estimated it to be approximately 1.571079; according to recent estimations \(10^{80}\)  .

To know more about proton visit:-

brainly.com/question/1252435

#SPJ10