Which set of elements has the MOST similar physical and chemical properties?


A. K, Ca, Sr

B. K, Cs, Fr

C. K, Ca, Rb

D. K, Sr, Li

Answer:

Products would be on the right. Reactants would be on the left

Explanation:

⁣\(5.6 \times 10^1^7\) atoms of phosphorus is equal to \(9.32 \times 10^-7\) moles.

Either a positively charged electron or a large number of negatively charged electrons surround the central nucleus of an atom. The positively charged nucleus is made up of two comparatively large particles called protons and neutrons.

As many atoms, molecules, or ions (referred to as entities) are present in one mole of substance as there are in  \(12\) grammes of carbon-\(12\), it is known as a mole. It is about equal to the Avogadro's number \(6.022 \times 10^23\)  , which is entities per mole.

We must divide this amount by Avogadro's number to get the number of moles in  \(5.6 \times 10^1^7\) atoms of phosphorus:

Number of moles =\((5.6 \times 10^17 atoms) / (6.022 \times 10^23 atoms/mol)\)

Number of moles = \(9.32 \times 10^-7\)mol

Therefore, ⁣\(5.6 \times 10^1^7\) atoms of phosphorus is equal to \(9.32 \times 10^-7\) moles.

Learn more about atom here:

https://brainly.com/question/30898688

#SPJ9

Answer:

2.4×1024 atoms.

Explanation:

Please mark me as brainliest

The full meaning of 3-pga is 3-phosphoglyceric acid. 3-pga is a very important chemical compound and it can be found in both the Glycolysis and Calvin -Benson cycle.

After 3-pga is phosphorylated, it is reduced by NADPH'

Phosphorylation is a chemical process of adding phosphate to a chemical compund.

NADPH is known as a cofactor in the Anabolic process. Its full meaning is Nicotinamide Adenine Dinucleotide Phosphate Hydrogen. It is an electron donor.

When 3-pga is phosphorylated, and additional phosphate is added to its chemical compound. During photosynthesis, NADPH reacts with Phosphorylated 3-pga and it undergoes a reduction reaction.

During the reduction reaction, 3-pga gains electrons.

Therefore, After 3-pga is phosphorylated, it is reduced by NADPH.

To learn more, visit the link below:

https://brainly.com/question/15636075

When a skeletal muscle lengthens, the stretch reflex is activated, causing the muscle to contract and resist excessive stretching, thus preventing injury.



When a skeletal muscle lengthens, it activates the stretch reflex, a protective mechanism that resists excessive stretching and potential injury. The muscle spindles within the muscle fibers detect the stretch and send signals to the spinal cord. In response, the spinal cord triggers the muscle to contract, preventing further stretching. This reflexive contraction helps maintain muscle integrity and prevents strains or tears.



However, it's important to remember that the stretch reflex has its limits, and extreme stretching can still cause muscle damage. Proper warm-up, gradual progression of exercise, and employing appropriate stretching techniques are essential for optimal muscle protection and injury prevention.



In summary,   When a skeletal muscle lengthens, the stretch reflex is activated, causing the muscle to contract and resist excessive stretching, thus preventing injury.

To learn more about injury click here

brainly.com/question/28450125

#SPJ11

Therefore, it takes approximately 23.2 kJ of energy to boil 100 mL of water.

The correct answer is D. 100 mL × 1g divided by 1mL × 1mol divided by 18.02g × 4.186 kJ/mol = 23.2 kJ

To calculate the energy required to boil 100 mL of water, we need to use the specific heat capacity of water, which is approximately 4.186 J/g·°C. The molar mass of water is 18.02 g/mol.

First, we convert the volume of water from milliliters to grams:

100 mL × 1 g/1 mL = 100 g

Then, we calculate the number of moles of water:

100 g × 1 mol/18.02 g = 5.548 mol

Finally, we multiply the number of moles by the molar heat of vaporization of water, which is approximately 40.65 kJ/mol:

5.548 mol × 4.186 kJ/mol = 23.2 kJ

Therefore, it takes approximately 23.2 kJ of energy to boil 100 mL of water.

Learn more about energy

https://brainly.com/question/8630757

#SPJ11

In a reversible reaction the conditions of the reaction determines the direction to which the equilibrium position will shift.

The equation of the reaction is;

2H2(g) + O2(g) + ⇄ 2H2O(g) + Heat

Learn more about reaction equilibrium:https://brainly.com/question/11114490

Answer:

Flushing goldfish down the toliet

Explanation:

This would help the planet because goldfish are a very evasive species that has been harming our natural enviroments lakes and rivers. Ever since people have been flushing them down the toliet including me since I've had over six they have been finding their ways into our ecosytem and damaging nature. You may think that goldfish are a cute and small pet species to keep in a fish tank but the fish can grow in the right conditons up to 16.1 inches long and can top over five pounds in the wild. Unfortunately most goldfish never thrive like this in fish tanks due to nasty inadequate housing and feeding conditions. And most do not live up to their expected life span in the wild of 15 to even thirty years due to their living conditons. Did you know, goldfish will actually jump out of their tank in a final desperate search for better living conditions and enviroment to live in to meet their physiological needs. But lets get back to the problem so don't be to quick to feel sorry for them, when people flush them down the toliet they repopulate somehow in our lakes and rivers. Even through, it is not clear how they got there, which the suspected culprit is the sewer system. They threaten the natural enviroment tho because they are obnivores and they eat a mixtures of plants and animal specimen. You are probrably thinking why is this a problem, well its because goldfish are particullary greedy eaters and will eat, eat, and feast on the natural envrioment they infestated. And the waste they leave on the enviroment will promote the growth of algae which could cause an extent of enviromental damage. Of course goldfish are not impacted by this algae growth for adaptation reasons which shield them. This is not the main problem tho the main problem of this is that female goldfish can produce up to 1000 eggs at a time. And to make things worse unlike other fish species where the parents of the eggs leave the eggs for predaetors and well the elements of nature the goldfish instead guard their nest foriciously from predaetors that eat fish eggs in which effectively shields the populations young from danger. And to just add to the chaos the goldfish sadly have no real natural predaetor in the unitedstates which just causes more problems since they have no one killing them. And did I mention that they could live up to a real possibility of thirty years. And that they are forocious eaters that could eat a variety of types of foods. All of these facts in the end lead to two things first stop flushing your pet goldfish down the toliet and secondly now you know how golfish impact our planet.

Give brainliest please it took me over thirty minutes of thinking!

The standard error of the sample mean is 2.68 cc (option C).

The standard error of the sample mean measures the variability or uncertainty of the sample mean compared to the population mean. It is calculated by dividing the standard deviation of the sample (s) by the square root of the sample size (n). In this case, the standard deviation is given as 12 cc, and the sample size is 20. By dividing 12 cc by the square root of 20, we obtain the standard error of the sample mean, which is 2.68 cc.

Learn more about Mean

brainly.com/question/30112112

#SPJ11

Answer:

Explanation:

A solid, at a given temperature, has a definite volume  

and shape which may be affected by changes in  

temperature. Solids usually increase slightly in size  

when heated (expansion)  and usually  

decrease in size if cooled (contraction).A liquid, at a given temperature, has a  

fixed volume and will take up the shape of any  

container into which it is poured. Like a solid, a  

liquid’s volume is slightly affected by changes in  

temperature.

A gas, at a given temperature, has neither a definite  

shape nor a definite volume. It will take up the shape  

of any container into which it is placed and will  

spread out evenly within it. Unlike those of solids  

and liquids, the volumes of gases are affected quite  

markedly by changes in temperature.

Answer:

a) longitudnal waves

b)parallel to vibration

c) transverse waves .it is used in a ripple tank

The molar mass of the unknown gas is approximately 4.28 g/mol.

What is molar mass?

The molar mass is the mass of a substance in grams that is equal to one mole of the substance. The mole is a unit of measurement in chemistry that represents the number of entities in a substance, such as atoms, molecules, or ions. One mole of any substance contains Avogadro's number of entities, which is approximately 6.022 x 10^23.

The rate of diffusion of a gas is inversely proportional to its square root of molar mass. This relationship is known as Graham's Law of Diffusion.

Given that CO2 diffuses 3.2 times faster than the unknown gas, we can set up the following equation:

(Diffusion rate of CO2) / (Diffusion rate of unknown gas) = 3.2

(1/√(molar mass of CO2)) / (1/√(molar mass of unknown gas)) = 3.2

Squaring both sides:

(1/molar mass of CO2) / (1/molar mass of unknown gas) = 3.2^2 = 10.24

Therefore,

(1/molar mass of unknown gas) = (1/molar mass of CO2) / 10.24

Given that the molar mass of CO2 is 44.01 g/mol,

(1/molar mass of unknown gas) = (1/44.01) / 10.24

Solving for molar mass of the unknown gas:

molar mass of unknown gas = 44.01 / 10.24 = 4.28 g/mol

So, the molar mass of the unknown gas is approximately 4.28 g/mol.

To learn more about molar mass:

https://brainly.com/question/21334167

#SPJ4

A radioactive substance decreases by 65% each hour. Find the hourly decay factor. The hourly decay factor is 0.35.

Chemicals in the class of radionuclides (also known as radioactive materials) have unstable atomic nuclei. They become stable by undergoing modifications in the nucleus (spontaneous fission, alpha particle emission, neutron conversion to protons, or the opposite).

A radioactive atom will naturally emit radiation in the form of energy or particles in order to transition into a more stable state. The difference between radioactive material and the radiation it emits must be made.

Learn more about radioactive, here:

https://brainly.com/question/18917411

#SPJ1

Answer:

here are several resons that fossil foraminifera are especially valuable for determining the relative ages of marine rock layers. They have been around since the Cambrian, over 500 million years ago. They show fairly continuous evolutionary development, so different species are found at different times.

As per the LeChatelier's principle, the reaction will shift to the right or forward direction.

The provided reaction is,

4NH₃ +5O₂ ⇔ 4NO+6H₂O

Now if we add the oxygen in the reaction, then the oxygen will be going to the reactant side of the reaction,

So, because the reactant concentration is increasing, the reaction will be increased in term of rate and reaction will shift to the right side of the reaction or the forward direction. Because the LeChatelier's principle, say that any change in the equilibrium of the system will be compensated by shifting of the reaction in the counterpartying direction of the reaction.

To know more about LeChatelier's principle, visit,

https://brainly.com/question/3384381

#SPJ4

Complete question - Use LeChatelier's principle is predict how the reaction will shift 4NH₃ +5O₂ ⇔ 4NO+6H₂O when added more oxygen.

The physical mechanism causing the change in strength when using brine as the pore fluid is the presence of salt ions that weaken the interparticle bonds. Salt can reduce the shear strength of clays by increasing the repulsive forces between clay particles.

The strength of clay types at 50% water content can vary depending on whether DI water or brine is used as the pore fluid. Generally, there is a significant difference in strength between the two.

The presence of salt in brine can have an effect on the shear strength of clays. When salt is dissolved in water, it creates ions that can interact with the clay particles. These interactions can lead to the formation of electrical double layers around the clay particles, which can increase the interparticle repulsion and decrease the shear strength of the clay.

On the other hand, when DI water is used as the pore fluid, there is no presence of salt ions to affect the interparticle interactions. As a result, the clay particles can have stronger bonds and higher shear strength compared to when brine is present.

Learn more about interparticle bonds here :-

https://brainly.com/question/4339576

#SPJ11

Answer:

A simpler answer: The reactivity of group 1 elements increases as you go down the group because:

the atoms become larger.

the outer electron becomes further from the nucleus.

the force of attraction between the nucleus and the outer electron decreases

Explanation:

Similar Explanation to the answer: The reactivity of alkali metals increases as we move down the group. As the atomic number increases, the atomic racfcus also increases and the single electron in the valence shell is located further away from the nucleus. Hence, Li is least reactive and Francium is the most reactive.

Answer:

A. Anticline

Explanation:

Answer:A

Explanation:

A family use a hot water heater fuelled by propane for their heating need. The amount of carbon dioxide emitted by the heater in a year assuming they use 2 kg of propane in a day and complete combustion of the propane is 2,175 kg.

To calculate the amount of carbon dioxide emitted by the propane heater in a year, we need to consider the molar mass of propane and the stoichiometry of its combustion reaction.

The chemical formula of propane is C₃H₈. Its molar mass can be calculated by summing the atomic masses of its constituent elements:

Molar mass of propane (C₃H₈) = (3 * atomic mass of carbon) + (8 * atomic mass of hydrogen)

Using the atomic masses from the periodic table, we have:

Molar mass of propane (C₃H₈) = (3 * 12.01 g/mol) + (8 * 1.008 g/mol) = 44.11 g/mol

To determine the amount of propane consumed in a year. Given that they use 2 kg (or 2000 g) of propane in a day, the amount of propane consumed in a year can be calculated as:

Propane consumption per year = (2000 g/day) * (365 days/year) = 730,000 g/year

To calculate the amount of carbon dioxide produced, we need to use the stoichiometry of the combustion reaction of propane:

C₃H₈ + 5O₂ → 3CO₂ + 4H₂O

From the balanced equation, we see that the molar ratio between propane and carbon dioxide is 1:3. Therefore, the moles of carbon dioxide produced can be calculated as:

Moles of CO₂ = (moles of propane) * (3 moles of CO₂ / 1 mole of propane)

Moles of CO₂ = (mass of propane) / (molar mass of propane) * (3 moles of CO₂ / 1 mole of propane)

Moles of CO₂ = (730,000 g) / (44.11 g/mol) * (3 mol CO₂ / 1 mol C₃H₈)

Moles of CO₂ = 49,426.82 mol

Finally, we convert moles of carbon dioxide to grams by multiplying by the molar mass of carbon dioxide:

Mass of CO₂ = (moles of CO₂) * (molar mass of CO₂)

Mass of CO₂ = (49,426.82 mol) * (44.01 g/mol) = 2,175,227.49 g

Rounding to a reasonable number of significant figures, the amount of carbon dioxide emitted by the propane heater in a year is approximately 2,175,227 g, or 2,175 kg.

To know more about propane here

https://brainly.com/question/14519324

#SPJ4

a) The sphere emits thermal radiation at a rate of 139.75 Watts.

b) The sphere absorbs thermal radiation at a rate of 37.66 Watts.

c) The sphere's net rate of energy exchange is 102.09 Watts.

To calculate the rates of thermal radiation emission and absorption, we can use the Stefan-Boltzmann law, which states that the rate of thermal radiation emitted or absorbed by an object is proportional to its surface area, temperature, and the Stefan-Boltzmann constant.

a) The rate of thermal radiation emitted by the sphere can be calculated using the formula:

Emitting Rate = emissivity * surface area * Stefan-Boltzmann constant * (\(temperature^4 - environment\ temperature^4\))

Plugging in the given values:

Emitting Rate = \(0.924 * (4\pi * (0.457)^2) * 5.67 \times 10^{-8} * ((32.2 + 273.15)^4 - (82.9 + 273.15)^4)\)

Emitting Rate ≈ 139.75 Watts

b) The rate of thermal radiation absorbed by the sphere can be calculated in a similar way but using the environment temperature as the object's temperature:

Absorbing Rate = emissivity * surface area * Stefan-Boltzmann constant * (\(environment\ temperature^4 - temperature^4\))

Plugging in the given values:

Absorbing Rate = \(0.924 * (4\pi * (0.457)^2) * 5.67 \times 10^{-8} * ((82.9 + 273.15)^4 - (32.2 + 273.15)^4)\)

Absorbing Rate ≈ 37.66 Watts

c) The net rate of energy exchange is the difference between the emitting rate and the absorbing rate:

Net Rate = Emitting Rate - Absorbing Rate

Net Rate = 139.75 Watts - 37.66 Watts

Net Rate ≈ 102.09 Watts

Therefore, the sphere emits thermal radiation at a rate of 139.75 Watts, absorbs thermal radiation at a rate of 37.66 Watts, and has a net rate of energy exchange of 102.09 Watts.

Note: The units for all the rates are Watts.

Learn more about thermal radiation emission

brainly.com/question/28517392

#SPJ11

Answer:

180g

Explanation:

So, 10 mole of water will weigh (18x10) = 180g.

\(\\ \rm\longmapsto Distance=Speed(Time)\)

\(\\ \rm\longmapsto Distance=25(2700)\)

\(\\ \rm\longmapsto Distance=67500m\)

The object travelling at 25 m/s, will travel a distance of 67500 m in 45 mins.

1 min = 60 s

Therefore,

45 mins = 45 × 60

Time = 2700

Speed = 25 m/s

Distance = speed × time

Distance = 25 × 2700

Therefore, the object will cover a distance of 67500 m in 2700 s (i.e 45 mins)

Learn more: https://brainly.com/question/14988345

Answer:

4

Explanation:

atoms of O2 in the product side:

(3×2)+(2×1)=8

so to balance it:

x × 2 =8

x=4

Answer:Tungsten changes oxidation numbers +6 to zero

Undergoes reduction

Explanation:

did it!

The process which involves simultaneous oxidation and reduction is known as redox process. Tungsten (W) changes oxidation numbers from +6 to zero, so it undergoes reduction. The correct option is D.

The process which involves the removal of oxygen or electronegative element element or addition of hydrogen or electropositive element is known as reduction. The given reaction is an oxidation-reduction reaction.

In terms of oxidation number, reduction can be defined as the process in which there occurs a decrease in the oxidation number of an atom or atoms. Here WO₃ is reduced to W. Because the oxidation number of 'W' decreases from +6 to 0.

In the balanced reaction, WO₃(s) + 3H₂(g) → W(s) + 3H₂O(g), there are oxidation and reduction reactions.

The reduction reaction is given as:

W⁺⁶ + 6e⁻ → W⁰

The oxidation reaction is represented as:

6H⁺¹ → 6H⁰ + 6e⁻

Thus the correct answer is option D.

To know more about redox reaction, visit;

https://brainly.com/question/2671074

#SPJ2

The concept of tradeoff and opportunity cost is evident in environmental decisions where individuals or entities must choose between desirable alternatives that compete with one another in a resource-limited environment.

Tradeoff refers to the action of sacrificing one desirable attribute or aspect for another desirable attribute. On the other hand, opportunity cost can be defined as the profit or benefit that an individual or entity loses when selecting one alternative over the other due to limited resources.

A popular environmental example that explains the concept of tradeoff and opportunity cost is an economy that depends on non-renewable energy resources such as coal, oil, and gas to drive industrial processes. In such an economy, if the government or any other stakeholders decide to reduce the consumption of non-renewable energy resources, there will be a tradeoff between environmental benefits and economic growth.

This is because industries require energy to function, and reducing their energy consumption will lead to reduced economic output and job losses. The opportunity cost of switching to renewable energy would be the financial and economic gains that non-renewable energy production offers.

However, this option also involves environmental degradation, and it comes with social and economic risks. Therefore, the government and other stakeholders must consider all the options and the potential impacts before deciding on what action to take.

Learn more about energy -

brainly.com/question/874116

#SPJ11

The heat energy absorbed by the water in the experiment according to the calorimeter data is 10450 J

From the question give above, the following data were obtained:

From calorimetry, we understood that heat absorbed is given by the following formula

Q = MCΔT

Inputting the given parameters, we can obtain the heat absorbed by the water as follow:

Q = 100 × 4.18 × 25

Q = 10450 J

Thus, we can conclude that the heat energy absorbed by the water is 10450 J

Learn more about heat energy absorbed:

https://brainly.com/question/29224546

#SPJ1

Answer:

acidos

Explanation:

los conductores de energía eléctrica: es decir, este tipo de energía fluye con facilidad a través de sus iones. Al reaccionar con metales generan hidrógeno (H) y sal. Al reaccionar con bases o con óxidos metálicas generan agua

Answer:

See explanation

Explanation:

The structure of ethylene is shown in the image attached. The two carbon atoms have a double covalent bond between them.

The two carbon atoms are sp2 hybridized. The bond between them is a covalent bond, there is one pi bond and one sigma bond between the carbon atoms. Between carbon and hydrogen, there are covalent bonds also. The covalent bonds are sigma bonds.

The pi bonds between carbon atoms is weaker than the sigma bonds between the carbon atoms. This is because, the side-by-side overlap the p orbitals in a pi bond is less effective than the end-to-end overlap of a sigma bond.

Answer:

You should never throw water on an electrical fire because water conducts electricity and you could be electrocuted.

Please mark 4 brainliests