Given the speed of light as 3.0 × 108 m/s, calculate the wavelength of the electromagnetic radiation whose frequency is 7.5 × 1012 Hz. Answer in units of m.

The percent composition of each element in vinegar, also known as acetic acid, is as follows: Carbon - 39.9%, Hydrogen - 6.7%, and Oxygen - 53.4%, calculated using their respective atomic masses and the molar mass of acetic acid.

The chemical formula for vinegar, which is also known as acetic acid, is C2H4O2. Each molecule of vinegar contains two atoms of Carbon (C), four atoms of Hydrogen (H), and two atoms of Oxygen (O). The percent composition of each element in vinegar can be calculated using their atomic masses and the overall molar mass of vinegar.

The molar mass of acetic acid is 60.06 g/mol. Using this information and the atomic masses of carbon (12.01 g/mol), hydrogen (1.01 g/mol), and oxygen (16.00 g/mol), we can calculate the percent composition by volume of each element in vinegar as follows: Carbon constitutes 39.9%, Hydrogen constitutes 6.7%, and Oxygen constitutes 53.4% of the total composition.

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Earthquakes may lead to

a) damage to buildings / houses

b) Tsunami

c) Damage to electricity supply

d) Life threatening Harm to animals

e) Life threatening harm to humans

Four dangers that are associated with earthquakes are tsunamis, landslides, soil liquefaction, and flood.

Further explanations:

Earthquake is defined as the sudden shivering of the Earth’s surface due to the release of energy from inside the Earth. The energy is released in the form of seismic waves which can range to such a large extent that it can toss people here and there and can even ruin a whole city.

Elastic rebound theory explains the process of discharge of energy during an earthquake. During the distortion of the Earth's Crust, the alternate sides of the Earth's crust suffer a shear stress and it continues until the internal rigidity exceeds. The fault separates along a rapture calls fault line and the sudden movement releases a mass-energy that divides the plates into two halves. The energy discharged during this process is known as Seismic Wave.

If the epicenter of the earthquake lies in the sea bed then it is sufficient to create Tsunami waves and can even lead to a volcanic eruption from inside the sea. In terrestrial area is more hazardous as it creates landslides, liquefaction, and devastating floods.

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Answer Details  

Grade: High School

Subject: Geography

Chapter: Earthquake

Keywords: Earthquake, seismic waves,Elastic rebound theory, earthquake, Earth's Crust, mass-energy, Seismic Wave,epicenter, Tsunami waves, volcanic eruption, landslides, liquefaction, devastating floods.

To find the number of atoms in 131.97 liters of water vapor at STP, divide the volume by 22.4 L/mol to get the moles, then multiply by Avogadro's number and the number of atoms per water molecule, resulting in approximately 1.0645 × 10²⁵ atoms.

The question asks how many atoms are in 131.97 liters of water vapor at STP (standard temperature and pressure), which is a chemistry problem involving concepts around molar volume and Avogadro's number.

At STP, one mole of an ideal gas occupies 22.4 liters.

Therefore, the number of moles of water vapor in 131.97 liters can be found by dividing the total volume by the volume of one mole, which results in approximately 5.89 moles of water vapor.

Since water (H2O) consists of 3 atoms per molecule and the number of molecules in one mole of any substance is 6.022 × 1023 (Avogadro's number), we can calculate the total number of atoms in the given volume of water vapor as follows:

5.89 moles × 3 atoms/molecule × 6.022 × 10²³ atoms/mole = 1.0645 × 10²⁵ atoms.

Therefore, the correct answer is D.) 1.0645 × 10²⁵ atoms.

Answer

Rutherford inferred the existence of a dense, positively charged nucleus based on results of a scattering experiment.

Explanation

Bohr proposed a planetary model of the atom to explain the emission spectrum of hydrogen. Hence option B is incorrect.

Einstein explained the observation of the photoelectric effect experiment by stating that light has particle-like properties. Hence option C is incorrect.

Schrödinger proposed that electrons have wave like nature.  Hence option D is incorrect.

Ernest Rutherford is correctly matched with his inference of a dense, positively charged nucleus based on a scattering experiment. He developed the nuclear model, which described the atom like a mini solar system. Niels Bohr used this model to explain the atomic spectrum of hydrogen.

Contribution to Atomic Theory

The scientist correctly matched with his contribution to atomic theory in the given options is Ernest Rutherford. Rutherford inferred the existence of a dense, positively charged nucleus based on the results of his gold foil scattering experiment. This discovery was crucial to the development of the nuclear model of the atom. Rutherford's model described the atom as having a tiny, dense nucleus surrounded by lighter, negatively charged electrons, resembling a mini solar system, which later became known as the planetary model of the atom.

It was Niels Bohr who, convinced by the validity of Rutherford's model, based his theory on it. Bohr's theory explained the atomic spectrum of hydrogen and established new principles in quantum mechanics. The identification of the proton as a component of the nucleus was indeed suggested by Rutherford in 1920, and he coined the term proton for the positively charged particles found there. However, contrary to one of the statements from the quiz, it is not correct to attribute the confirmation of the existence of protons to Bohr. Additionally, Einstein's photoelectric effect experiment did establish the particle-like properties of light but wasn't directly related to the structure of the atom. The discovery of the neutron is credited to James Chadwick in 1932, a student of Rutherford, not to Rutherford himself.

Answer:

Answer:

The symbol in the parenthesis indicate (C) the physical state of each reactant and product

Explanation:

There are symbols used to represent the physical state of a reactant or product, the most common being (s) for solid, (l) for liquid, (g) for gas, and (aq) for aqueous, or water like. Precipitate is also considered a physical state and is represented by a downward-facing arrow. In this case, the only symbols used in the chemical equation are (aq) and (s). Therefore, C is the correct answer.

[tex]CaCl_{2(aq)} + 2AgNO_{3(aq)}[/tex] → [tex]Ca(NO_{3})_{2(aq)} + 2AgCl_{(s)}[/tex]

The other answers:

A. the catalyst used in the reaction

Because it is neither a reactant nor a product, a catalyst is shown in a chemical equation by being written above the yield arrow. The yield arrow is what would be the equals sign in a normal equation.

B.  the number of atoms of each reactant and product

These are represented by the subscripts. In the given chemical equation, these numbers are 2, 3, 3, and 2 (left to right).

D.  the number of units of each reactant and product

These are represented by the coefficients. In the given chemical equation, these numbers are 1, 2, 1, and 2 (left to right). The ones are implied, so there's no need to write them down.

I hope this helps!

The correct answer is "The addition or removal of energy".

Answer:

[tex]V_{m} = \frac{V}{n}[/tex]

Explanation:

Molar volume is the volume occupied by 1 mole of a substance.

For gases, based on the ideal gas law we have:

[tex]PV = nRT[/tex]

where, P = pressure, V= volume, n = moles, R = gas constant, T = temperature

[tex]\frac{V}{n} = \frac{RT}{P}[/tex]

Here, the molar volume is given as:

[tex]V_{m} = \frac{V}{n}[/tex]

Under standard temperature and pressure conditions, the molar volume of an ideal gas is 22.4 L/mol

An element belongs to particular group is related to the number of electrons present in the outer shell of the atoms. In given case, group is 2, therefore, number of valence electrons is 2 implies it has ability to lose two electrons to get +2 charge.

[tex]A\rightarrow A^{+2}+2e^{-}[/tex]

Therefore, ion formed after removal of two electrons is [tex]A^{2+}[/tex].

Hence, option (D) is the correct answer.

The ion of an element from Group 2A can be represented as D. A²⁺

The periodic table shows the arrangement of elements into groups and periods.

Group II elements are elements with 2 electrons in the outermost shell (hence they have 2 valence electrons).

Group II element can lose this 2 valence electrons thereby forming a +2 cation.

The ion of an element from Group 2A can be represented as D. A²⁺

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Hello!

Find the Energy of the Photon by Planck's Equation, given:

E (photon energy) =? (in Joule)

h (Planck's constant) = [tex] 6.626*10^{-34}\:J * s [/tex]

f (radiation frequency) = [tex] 8*10^{12}\:Hz [/tex]

Therefore, we have:

[tex] E = h*f [/tex]

[tex] E = 6.626*10^{-34}*8*10^{12} [/tex]

[tex] E = 53.008*10^{-34+12} [/tex]

[tex] E = 53.008*10^{-22} [/tex]

[tex] \boxed{\boxed{E = 5.3008*10^{-21}\:Joule}}\end{array}}\qquad\checkmark [/tex]

I Hope this helps, greetings ... DexteR! =)

The energy of an electromagnetic wave with a frequency of 8 × 1012 Hz is calculated using the formula E = hf. Using Planck's constant, 6.626 × 10-34 J·s, the energy is found to be 5.3008 × 10-21 Joules.

To find the energy of an electromagnetic wave with a given frequency, we use the formula E = hf, where E is the energy, h is Planck's constant, and f is the frequency of the wave. Planck's constant (h) is approximately 6.626 × 10-34 J·s. Therefore, for an electromagnetic wave with a frequency of 8 × 1012 Hz, the energy can be calculated as follows:

The energy of an electromagnetic wave with a frequency of 8•1012 Hz can be calculated using Planck's equation: E = hf, where E is the energy, h is Planck's constant (6.626 x 10-34 J•s), and f is the frequency in Hz.

E = hf = (6.626 × 10-34 J·s) × (8 × 1012 Hz)

Now multiply the two numbers:

E = 5.3008 × 10-21 J

Plugging in the values, we get:

E = (6.626 x 10-34 J•s) × (8•1012 Hz)

Simplifying, the energy is approximately 5.3 x 10-21 J.

So, the energy of an electromagnetic wave with a frequency of 8 × 1012 Hz is 5.3008 × 10-21 Joules. This formula is critical in understanding the relationship between the frequency of electromagnetic radiation and its energy, and is a cornerstone of quantum mechanics.

The answer is: B. metal.

Metals conduct an electric current in liquid and solid state, because they have mobile electrons.

Metallic bond is formed between electrons and positively charged metal ions.

Metallic bond increace electrical and thermal conductivity.

For example, thermal conductivity of sodium is 140 W/(m·K).

Nonmetals have low electrical and thermal conductivity.

Answer: The correct answer is Option A.

Explanation:

Enthalpy change is defined as the difference in enthalpies of all the product and the reactants each multiplied with their respective number of moles. It is represented as [tex]\Delta H^o[/tex]

The equation used to calculate enthalpy change is of a reaction is:  

[tex]\Delta H^o_{rxn}=\sum [n\times \Delta H^o_f(product)]-\sum [n\times \Delta H^o_f(reactant)][/tex]

For the given chemical reaction:

[tex]PbO(s)+CO(g)\rightarrow Pb(s)+CO_2(g);\Delta H^o=-131.4kJ[/tex]

The equation for the enthalpy change of the above reaction is:

[tex]\Delta H^o_{rxn}=[(1\times \Delta H^o_f_{(Pb(s))})+(1\times \Delta H^o_f_{(CO_2(g))})]-[(1\times \Delta H^o_f_{(PbO(s))})+(1\times \Delta H^o_f_{(CO(g))})][/tex]

We are given:

[tex]\Delta H^o_f_{(CO_2(g))}=-393.5kJ/mol\\\Delta H^o_f_{(CO(g))}=-110.5kJ/mol\\\Delta H^o_f_{(Pb(s))}=0kJ/mol\\\Delta H^o_{rxn}=-131.4kJ[/tex]

Putting values in above equation, we get:

[tex]-131.4=[(1\times \Delta H^o_f_{(0)})+(1\times (-393.5))]-[(1\times \Delta H^o_f_{(PbO(s))})+(1\times (-110.5))]\\\\\Delta H^o_f_{(PbO(s))}=-151.6kJ/mol[/tex]

Hence, the correct answer is Option A.

Answer: The order with respect to B is

Explanation: Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

[tex]Rate=k[A]^x[B]^y[/tex]

k= rate constant

x = order with respect to A

y = order with respect to B

n = x+y = Total order

a) From trial 1: [tex]20=k[0.20]^x[0.10]^y[/tex]    (1)

From trial 2: [tex]40=k[0.20]^x[0.20]^y[/tex]    (2)

Dividing 2 by 1 :[tex]\frac{40}{20}=\frac{k[0.20]^x[0.20]^y}{k[0.20]^x[0.10]^y}[/tex]

[tex]2=2^y,2^1=2^y[/tex] therefore y=1.

Thus order with respect to B is 1.

Given the data in the accompanying table, the reaction order for B is 1st order. The correct option is B.

We may study how the initial rate of the reaction varies when the initial concentration of B is changed to establish the reaction order for B.

We can detect the link between the rate and the concentration of B by comparing the start rate of the reaction at different initial concentrations of B.

Based on the information provided:

Initial concentration of B: [B] (mol/L)

Initial rate: mol/Ls

When [B] is 0.20 mol/L, the initial rate is 20 mol/Ls.

When [B] is 0.40 mol/L, the initial rate is 160 mol/Ls.

As we can see, increasing the initial concentration of B (from 0.20 mol/L to 0.40 mol/L) doubles the initial rate (from 20 mol/Ls to 160 mol/Ls). This suggests that the starting rate and the concentration of B have a direct proportional connection.

Here, one can conclude that the reaction order for B is 1st order. Therefore, the correct answer is B) first.

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The four groups attached to the central carbon of an amino acid are an amino group ([tex]\rm -NH_2[/tex]), a carboxyl group ([tex]\rm -COOH[/tex]), a hydrogen atom ([tex]\rm -H[/tex]), and a side chain group (also called an R group).

Amino acid is an organic compound which is defined as the amine substituted carboxylic acid.

-The amino group (-NH2) and carboxyl group (-COOH) are both functional groups that are involved in the formation of peptide bonds between amino acids during protein synthesis.

-The hydrogen atom (-H) is simply a single proton that is attached to the central carbon atom of the amino acid.

-The side chain group (R group) is a variable group that differs between different amino acids. The R group can be a simple alkyl group, a complex aromatic group, or a charged group, among others.

Therefore, an amino group ([tex]\rm -NH_2[/tex]), a carboxyl group ([tex]\rm -COOH[/tex]), a hydrogen atom ([tex]\rm -H[/tex]), and a side chain group (also called an R group) are the four groups attached to the central carbon of an amino acid.

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Final answer:

Amino acids have four distinct groups attached to a central alpha carbon: an alpha-amine group, an alpha-carboxyl group, a hydrogen atom, and a variable R-group unique to each amino acid.

Explanation:

Every amino acid consists of four groups covalently attached to a central alpha carbon, also known as the α-carbon. These include:

This structure is essential in biology for protein synthesis, as amino acids are the building blocks of proteins. Each amino acid's specific R-group influences the protein's structure and function.

Answer: Option (A) is the correct answer.

Explanation:

When a solute is dissolved in a solvent then in order to dissolve the solute it is necessary that attractive forces between the solute must be broken such that solute molecules can combine with solvent molecules.

By increasing temperature, pressure, surface area etc of a solution we can break the attractive forces between the solute.

Thus, we can conclude that in order for a solute to dissolve in a solvent it is true that the attractive forces in a solute need to be broken.

Answer: B. Hardness

Explanation:

Qualitative properties are properties that are observed and can generally not be measured using a numerical value. Example : Cleavage,  Luster , streak

Quantitative properties are properties that are observed and can generally  be measured using a numerical value. Example: hardness

Hardness of minerals is the resistance of a material to deformation. It is measured using Moh's scale which ranges from 1 to 10 and thus have a numerical value.

Thus Hardness is a quantitative property of minerals.

Toasting bread is a chemical change because it causes chemical reactions that create new substances with different properties than the original bread. The Maillard reaction during toasting forms new compounds, making this process irreversible.

Toast is an example of a chemical change because the process of toasting bread results in the bread undergoing chemical reactions that change its chemical composition. When you heat bread in a toaster, the carbohydrates in the bread undergo a process called the Maillard reaction, which creates new compounds like melanoidins that give toast its distinctive flavor and color. The heat also causes starches to break down into simpler sugars. These changes are not reversible, creating new substances with different chemical properties than the original bread. Therefore, toasting bread is a chemical reaction and not a physical change.

Letter A. do not react with other or chemically.

When water changes from a liquid to a vapor: They move farther apart.

The molecule is a collection of extra atoms that shape the smallest identifiable unit into which a pure substance may be divided and still maintain the composition and chemical properties of that substance.

A molecule may be homonuclear, this is, it consists of atoms of 1 chemical detail, e.g. atoms in the oxygen molecule (O2); or it is able to be heteronuclear, a chemical compound composed of a couple of detail, e.g. water two hydrogen atoms and one oxygen atom; H2O.

Atoms and complexes linked by means of non-covalent interactions, consisting of hydrogen bonds or ionic bonds, are typically no longer considered unmarried molecules.

Molecules as components of matter are common. additionally they make up maximum of the oceans and surroundings. maximum organic materials are molecules. The substances of existence are molecules, e.g. proteins, the amino acids of which they may be composed, the nucleic acids (DNA and RNA), sugars, carbohydrates, fat, and nutrients. The nutrient minerals are normally ionic compounds, consequently they're now not molecules, e.g. iron sulfate

varieties of MOLECULES

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The Lewis formula is structural representation that indicates the bonding between atom of a molecule by line and dots used to indicates the electron position around the atoms, electron pair is known as lone pair of electrons shown by pair of dots. The electrons indicated in the structure are valence electrons.

The given atoms are [tex]N (g)[/tex] and [tex]O (g)[/tex].

[tex]N (g)[/tex], whose atomic number is 7.

Electronic configuration for [tex]N (g)[/tex] is [tex]2, 5[/tex].

Number of valence shell electrons for [tex]N (g)[/tex] is 5.

[tex]O (g)[/tex], whose atomic number is 8.

Electronic configuration for [tex]O (g)[/tex] is [tex]2, 6[/tex].

Number of valence shell electrons for [tex]O (g)[/tex] is 6.

The Lewis formula for [tex]N (g)[/tex]  and [tex]O (g)[/tex] is shown in the image.

The atoms combine to form molecule in order to complete their octet that is to get 8 electrons in their valence shell and get stabilize in nature.

The total number of valence shell electrons in [tex]NNO(g)[/tex] is:

[tex]2(5)+6 = 16 electrons[/tex]

The distribution of electrons in the atom will take place in such a way that formation of triple bond will take place between two nitrogen atoms and a single bond will form between nitrogen and oxygen atom. In order to complete their octet, the nitrogen atom in center will possess 1+ formal charge and oxygen will possess 1- charge (oxygen is  electronegative atom). Thus, results in formation of neutral molecule.

The formal charge on each atom is calculated using:

[tex]Valence electrons - Nonbonding electrons - \frac{Bonding electrons}{2}[/tex]

The Lewis formula of [tex]NNO(g)[/tex] is shown in the image.

The Lewis structure corresponding to the reactants and products in the reaction is attached in the image.

Further Explanation:

The free radicals are high energy chemical species that must stabilize themselves either via electron combination with another free radical or abstraction of proton from another radical.

The Lewis structure is the chemical representation of an element along with the nonbonding pairs. For covalent molecules, the number of electrons involved in bonding and the remaining nonbonding pairs can be represented while writing the Lewis structures. Lewis structures along with the formal charges that they carry help predict the geometry, polarity, and reactivity of the molecules.

The nitrogen radical itself is unstable, and nitrogen monoxide also has an unpaired electron. So these two reactants can stabilize themselves by combination of their unpaired electron and form dinitrogen oxide molecule.

Lewis structure of [tex]{{\mathbf{N}}_{\mathbf{2}}}{\mathbf{O}}[/tex]:

The total number of valence electrons of [tex]{{\text{N}}_{\text{2}}}{\text{O}}[/tex]  is calculated as,

Total valence electrons = [(2) (Valence electrons of N) + (1) (Valence electrons of O)]

[tex]\begin{aligned}{\text{Total valence electrons}}\left({{\text{TVE}}}\right)&=\left[ {\left(2\right)\left(5\right)+\left({\text{1}}\right)\left(6\right)}\right]\\ &=16\\ \end{aligned}[/tex]

Formal charge:

It is the charge that an atom acquires in a molecule assuming that the electron pairs that constitute the bond pairs are shared equally between the two atoms, irrespective of their electronegativities.

The formula to calculate the formal charge on an atom is as follows:

[tex]{\text{Formal charge}}&=\left[\begin{aligned}\left[\begin{gathered}{\text{total number of valence electrons}}\hfill\\{\text{in the free atom}}\hfill\\\end{gathered}\right]-{\text{ }}\\\left[{{\text{total number of non - bonding electrons}}}\right]-\\\frac{{\left[{{\text{total number of bonding electrons}}}\right]}}{{\text{2}}}\\\end{aligned}\right][/tex]

O forms one single bond with a nitrogen atom and 3 lone pairs are present on it.

Total number of valence electrons in the free oxygen atom is 6.

Total number of nonbonding electrons in O is 6.

Total number of bonding electrons in O is 2.

Substitute these values in equation (1) to find the formal charge on O.

[tex]\begin{aligned}{\text{Formal charge on O}}&=\left[{6 - 6 - \frac{2}{2}} \right]\\&=- 1\\\end{aligned}[/tex]

Total number of valence electrons in the free nitrogen atom is 5.

Total number of nonbonding electrons in N is 0.

Total number of bonding electrons in N is 6.

Substitute these values in equation (1) to find the formal charge on N.

[tex]\begin{aligned}{\text{Formal charge on N}}&=\left[{5 - 0 - \frac{8}{2}}\right]\\&=5 - 4 \\&=+1\\\end{aligned}[/tex]

The formal charge of nitrogen is  +1.

Nitrogen atom has 5 valence electrons, and oxygen atom has 6 valence electrons. The central nitrogen atom forms a triple bond with other nitrogen atom and a single bond with oxygen atom. The central nitrogen atom, therefore, acquire positive charge and oxygen atom will acquire negative charge. Therefore the Lewis structure of [tex]{{\mathbf{N}}_{\mathbf{2}}}{\mathbf{O}}[/tex]  is attached in the image.

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Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Molecular structure and chemical bonding

Keywords: Lewis structure, valence electrons, NO, formal charge, N2O, oxygen, double bonds, single bond, bonding electrons, non-bonding electrons, total valence electrons and resonance hybrid.

Hydrogen is obtained as a byproduct during the electrolysis of water. This involves passing an electrical current through water containing an electrolyte such as sulphuric acid. The process results in twice the volume of hydrogen gas at the cathode compared to oxygen at the anode because hydrogen is diatomic.

Hydrogen can be economically obtained as a byproduct in the electrolysis of water, a common electrolyte. This process involves the passage of direct current electricity through water, which contains an electrolyte such as H₂SO₄ (sulphuric acid). The hydrogen forms at the cathode (negative electrode), and oxygen evolves at the anode (positive electrode). The electrolysis of water, therefore, produces stoichiometric amounts of oxygen gas at the anode and hydrogen at the cathode, with twice the volume of hydrogen gas produced due to the fact that hydrogen is diatomic.

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Answer: Option (b) is the correct answer.

Explanation:

The energy necessary to remove an electron from a gaseous atom or ion is known as ionization energy.

This means that smaller is the size of an atom more amount of energy has to be supplied to it in order to remove the valence electron. This is because in small atom or element there will be strong force of attraction between the nucleus and electrons.

So, high amount of energy has to be supplied to remove the valence electrons.

As electronic configuration of helium is [tex]1s^{2}[/tex]. So, due to completely filled valence shell it is more stable in nature.

As a result, we need to provide very high amount of energy to remove an electron from a helium atom.

Thus, we can conclude that out of the given options helium element would the first ionization energy of the atom be higher than that of the diatomic molecule.

Final answer:

The element for which the first ionization energy of the atom would be higher than that of the diatomic molecule is boron.

Explanation:

The element for which the first ionization energy of the atom would be higher than that of the diatomic molecule is boron (option a).

Ionization energy is the energy required to remove an electron from an atom or molecule. In the case of boron, removing an electron from the filled 1s² subshell requires much more energy compared to the diatomic molecule. The first ionization energy values for boron, beryllium, and carbon are given as follows: B: 25,026 kJ/mol, Be: 6223 kJ/mol, C: 7475 kJ/mol. As you can see, boron has a much higher first ionization energy.

Answer: 1. For a endothermic reaction , energy is absorbed

2. The temperature recorded by a thermometer in an endothermic reaction would be reduced.

Explanation:

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and [tex]\Delta H[/tex] which is difference between energy of products and energy of reactants come out to be positive.  The temperature of the surroundings will decrease.

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and [tex]\Delta H[/tex] which is difference between energy of products and energy of reactants comes out to be negative.The temperature of the surroundings will increase.

Final answer:

The cohesion-tension theory explains how water ascends in plants via the xylem, driven by water molecule cohesion and tension from evaporation in the leaves, creating a negative water potential gradient.

Explanation:

The cohesion-tension theory is a scientific model that explains the process of water movement within plants. According to this theory, water is able to move upwards from the roots to the leaves via the xylem due to the cohesive properties of water molecules and the tension created by water evaporation. Cohesion refers to the tendency of similar molecules to stick together, which is particularly strong among water molecules due to hydrogen bonding. As water evaporates from the mesophyll cells in the leaves, it creates a negative water potential gradient, effectively pulling more water up through the plant's xylem vessels, akin to a continuous water column. This tension is further aided by the adhesive forces between the water molecules and the walls of the xylem cells.