The regions of space around the nucleus of an atom that can be occupied by one or two electrons with identical energy are called orbitals.
What are the orbitals of the nucleus of an atom?An orbital is a region of space around the nucleus of an atom where electrons are likely to be found. The orbitals of the nucleus of an atom are the shells in which the electrons are found.
The different orbitals have different shapes and energies, and the electrons in different orbitals interact with each other in different ways.
The electrons in the different orbitals interact with each other through a variety of processes, including electrostatic attraction, exchange forces, and spin-orbit coupling. These interactions can lead to changes in the electron’s energy levels, which can affect the properties of the orbital b.
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which pollutant would you suggest the government try to limit in order to slow down the breakdown of the marble on the taj mahal
Answer:
SO2
Explanation:
SO2 causes acid rain which is leading to dissolving of the marble on the Taj Mahal
SO2 reacts with water to come down as sulfuric acid during acid rains
A 20. 0-ml sample of 0. 30 m hbr is titrated with 0. 15 m naoh. What is the ph of the solution after 40. 3 ml of naoh have been added to the acid?.
The ph of the solution after 40. 3 ml of NaOH have been added to the acid is 10.
Titration is a commonplace laboratory technique of quantitative chemical analysis to determine the attention of an identified analyte. A reagent, termed the titrant or titrator, is ready as a trendy answer of recognized awareness and extent.
Calculation:-
Normality of acid normality of base
= nMV nMV
= 1 × 0. 30 × 0.02 1 × 0. 15 ×0.0403 L
= 6 × 10⁻³ = 6.1 × 10⁻³
overall base will be high
net concentration = 6.1 × 10⁻³ - 6 × 10⁻³
= 0.1 × 10⁻³
= 1 × 10⁻⁴
p0H = -log[1 × 10⁻⁴]
= 4
pH = 14 - 4
= 10
A titration is defined as 'the manner of determining the amount of a substance A by using adding measured increments of substance B, the titrant, with which it reacts till precise chemical equivalence is completed the equivalence factor.
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Describe how a state function depends on the pathway between the initial and final states of a system.
A state function only depends on the thermodynamic system's starting and current states.
What exactly is a "thermodynamic system"?A thermodynamic system is a collection of objects or a significant region of space. The surroundings or mass outside the system is referred to as such, and the border is the region separating the two.
For instance, if we are examining a car engine, the thermodynamic system is the gasoline burning inside the engine's cylinder, and the system's surrounds are the radiator, exhaust system, piston, and outside air. The inner surfaces of the cylinder and piston then form the boundary.
The cosmos is made up of the system and its surroundings. Thermodynamic systems can be classified as open, closed, or isolated. With its surroundings, an open system can interchange both matter and energy. Since heat and water vapor can be lost to the air, the stovetop example would be considered an open system.
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In a solution with a pH of 3 a. Litmus Is blue and phenolphthalein is colorless b. Litmus is blue phenolphthalein is red c. Litmus Is red phenolphthalein is colorless d. Litmus is red phenolphthalein is red.
Answer
c. Litmus Is red phenolphthalein is colorless
Explanation
A solution with a pH of 3 is acidic. The main use of litmus is to test whether a solution is acidic or basic, blue litmus turns red under acidic conditions, and red litmus turns blue under basic or alkaline conditions. Phenolphthalein is often used as an indicator in acid–base titrations. phenolphthalein, it turns colorless in acidic solutions and pink in basic solutions.
Therefore, the correct option for a solution with a pH of 3 is:
c. Litmus Is red phenolphthalein is colorless
Bauxite consists mainly of AlOs, which react with carbon at high temperatures.
The process uses large amounts of electric power; that's why it makes sense to recycle aluminum cans. The balanced equation for the reaction is
A1203 (s) + 3 C (s) ---> 2 AI (1) + 3 CO (g)
Suppose you react 25.0 grams of AlO, with 15.0 grams of carbon.
a. Determine which reagent is limiting and which is excess.
b. What theoretical yield (grams) of aluminum metal can be formed?
c. What mass of the excess reactant will be left over?
pls help me!!!
Based on the balanced equation of the reaction of bauxite and carbon;
a. the limiting reagent is Al₂O₃ amd the excess reagent is carbon, C.
b. the theoretical yield of aluminum metal is 13.23 grams
c. the mass of the excess reactant left over is 6.18 grams
What is the balanced equation of the reaction?The balanced equation of the reaction of bauxite and carbon is given below as follows:
Al₂O₃ (s) + 3 C(s) ---> 2 Al (s) + 3 CO (g)
Based on the equation of the reaction, the mole ratio of the reactants is 1 mole of Al₂O₃ to 3 moles of C.
Mole of a substance = mass / molar mass
Moles of Al₂O₃ in 25.0 g sample = 25 / 102
Moles of Al₂O₃ = 0.245 moles
Moles of C in 15.0 grams sample = 15 / 12
Moles of C in 15.0 grams sample = 1.25 moles
moles of C required = 0.245 * 3
moles of C required = 0.735 moles
Based on the mole ratio, C is the excess reactant and the limiting reagent is Al₂O₃
The theoretical yield of aluminum will be calculated from the mole ratio of Al₂O₃ and Al as follows:
Theoretical yield of Al = 0.245 * 2/1 * 27 g
Theoretical yield of Al = 13.23 grams
Moles of C leftover = 1.25 - 0.735
Mass of C left over = (1.25 - 0.735) * 12 g
Mass of C left over = 6.18 grams
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What is the correct electron configuration for Si atomic number
O A. 1s22s22p 3s23p²
OB. 1s22s22p 3s²3p³
O C. 1s22s22p63s²2d³
O D. 1s22s22p63s¹3p³
1s22s22p63s^13p^3 is correct electron configuration for SI atomic number.
What is electron configuration?
The distribution of electrons in an element's atomic orbitals is described by the element's electron configuration. Atomic electron configurations adhere to a standard notation in which all atomic subshells that contain electrons are arranged in a sequence with the number of electrons they each hold written in superscript. For instance, sodium's electron configuration is 1s22s22p63s1. Long electron configurations are frequently produced by the standard notation. In these circumstances, a shortened or condensed version of the standard notation may be used. The sequence of fully filled subshells that represent the electronic configuration of a noble gas are replaced in the abbreviated notation by the symbol for that noble gas enclosed in square brackets.
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Which transition of an electron in the hydrogen atom emits a photon with the smallest amount of energy?.
E3 is least transition of an electron in the hydrogen atom emits a photon with the smallest amount of energy.
A hydrogen atom is an atom belonging to the element hydrogen in chemistry. One positively charged proton and one negatively charged electron are both present in the electrically neutral atom and are held to the nucleus by the Coulomb force. Normal circumstances are infrequent for lone neutral hydrogen atoms. Hydrogen atoms can also exist in cationic and anionic states, however neutral hydrogen is frequently seen when it is covalently joined to another atom.
Energy is the quantifiable attribute that is transferred to a body or a physical system in physics. It is observable in the production of work as well as in the form of heat and light. The law of conservation of energy asserts that although energy can be changed in form, it cannot be created or destroyed. Energy is a conserved quantity.
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ASAP
Compare the heat energy in a teaspoon of boiling water and a swimming pool full of room temperature water.
This is an essay question
The heat energy teaspoon of boiling water and a swimming pool full of room temperature water then swimming pool have more heat energy than the teaspoon of boiling water
Heat energy is the result of movement of tiny particles called as atom, molecule, or ion in solid liquid and gases and heat energy is the transfer from one object to the another and in Celsius scale water freezes at 0°C and boil at 100°C to 90°C however the swimming pool contains a lot more water therefore the pool has more thermal energy than the cup of tea even though the tea is hotter than the water in the pool that's why heat energy is more in the swimming pool then in teaspoon of boiling water
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The change in temperature of 150.0 g of chloroform is 6.9 degrees Celsius. When it absorbs 1000.0 joules of heat, and the specific heat of chloroform is 0.96 J/g x C. Find the initial temp
Based on the temperature change and specific heat of chloroform, the initial temperature will be found as follows:
initial temperature = final temperature - temperature changeWhat is the change in the temperature of chloroform after it absorbs 1000.0 joules of heat?The change in the temperature of chloroform after it absorbs 1000.0 joules of heat is determined using the formula below:
Heat change or absorbed = mass * specific heat capacity * temperature changeHence;
Temperature change = heat absorbed / (mass * specific heat capacity)
The heat absorbed = 1000 Joules
mass of chloroform = 150.0 g
specific heat of chloroform = 0.96 J/g.C
Temperature change = 1000 / (150 * 0.96)
Temperature change = 6.9 °C
Also:
Temperature change = Final temperature - Initial temperature
Initial temperature = Final temperature - Temperature change
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Why do scientists clone banana plants, but not humans?
Answer:
There are legal and ethical restrictions regarding human cloning.
Explanation:
Answer:
Scientists clone banana plants and not humans because there are legal and ethical restrictions regarding human cloning.
[tex]hope \: this \: helped \: you \: [/tex]
what mass of ag2so4 will precipitate when 500.0 ml of 0.30 m agno3 is combined with 500.0 ml of 0.15 m na2so4? ag2so4: ksp
The mass of [tex]Ag_2SO_4[/tex] precipitate that would be formed would be 23.38 grams.
Stoichiometric problemAqueous [tex]AgNO_3[/tex] and aqueous [tex]Na_2SO_4[/tex] combine in a chemical reaction to form [tex]Ag_2SO_4[/tex] precipitate according to the following equation:
[tex]2AgNO_3 + Na_2SO_4 -- > Ag_2SO_4 + 2NaNO_3[/tex]
From the equation of the reaction, the mole ratio of the two reactants is 2:1.
Stoichiometrically, it means 2 moles of [tex]AgNO_3[/tex] require 1 mole of [tex]Na_2SO_4[/tex] for a complete reaction.
Recall that: mole = molarity x volume
Thus:
500 mL, 0.30 M [tex]AgNO_3[/tex] = 500/1000 x 0.3= 0.15 moles
500 mL. 0.15 M [tex]Na_2SO_4[/tex] = 500/1000 x 0.15= 0.075 moles
This means that the two reactants are stoichiometrically balanced.
Mole ratio of [tex]Na_2SO_4[/tex] and [tex]Ag_2SO_4[/tex] = 1:1
Thus, the equivalent mole of [tex]Ag_2SO_4[/tex] will be 0.075 moles.
The molar mass of [tex]Ag_2SO_4[/tex] = 311.799 g/mol
Mass of 0.075 moles [tex]Ag_2SO_4[/tex] = 0.075 x 311.799
= 23.38 grams
In other words, the mass of [tex]Ag_2SO_4[/tex] that will precipitate from the reaction would be 23.38 grams.
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The final digit in a measurement is obtained by estimating between the smallestmarked lines.a) Trueb) False
Answer:
[tex]A:\text{ True}[/tex]Explanation:
Here, we want to get how the final digit in a measurement is obtained
Mathematically, the final digit can be obtained by estimation
Hence, we say that the value is uncertain
The final digit is obtained by a mark or between the last mark and the next mark in a measurement
Thus, we call this value uncertain since it is estimated
The combustion of phosphorus trichloride yields diphosphorus pentoxide and dichlorine monoxide. How many liters of oxygen are needed to burn 25.0 L of PCl3?
All I need help with is the balanced reaction please
Answer:1. How many moles is 400.0 g of Al 2(SO4)3?
Mol = mass/molar mass
Mol = 400.0g/342g/mol = 1.169 mol
2. Which is the percent composition of bromine in the compound NaBr?
% Br = (mass Br/mass NaBr) x 100
% Br = (79.90g/102.88g) x 100 = 77.7%
3.How many molecules are in 3.6 grams of NaCl?
Molecules NaCl = 3.6g NaCl x 6.02 x 1023 NaCl molecules = 3.7 x 1022 molecules
58.43g NaCl
4.How many grams are in 1.946 moles of NaCl?
From Mol = mass/molar mass,
Mass = mol x molar mass
Mass NaCl = 1.946 mol x 58.43 g = 113.7 g
Explanation:
Which statement below explains why some microorganisms have the ability to repair a malfunctioning gene by using the human version of the gene?
A
Both organisms are classified in the same kingdom.
The genome of both organisms is identical.
(C) The genetic code of all living organisms is universal.
D
Microorganisms are typically lower level prokaryotes while humans are higher level eukaryotes.
The statement the genetic code of all living organisms is universal explains why some microorganisms have the ability to repair a malfunctioning gene by using the human version of the gene (Option C).
What is the genetic code?The genetic code is a set of instructions to encode protein by using specific triplets of nucleotides or codons, which indicate particular amino acids that will be added during translation.
Therefore, with this data, we can see that the genetic code is a group of instructions to produce proteins that are conserved in the tree of life.
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The frequency of a wave is 2.8 x 10^3 Hertz. What is the wavelength of these gamma rays?
Show all work!
The frequency of a wave 2.8 x 10³ Hertz is then the wavelength of these gamma rays is 107 nm
Wavelength is the the distance between two successive crests or troughs of a wave
Here given data is
Frequency = 2.8 x 10³ Hertz
Velocity of gamma rays = 3×10⁸m/s
We have to calculate wavelength of these gamma rays?
So, wavelength = velocity/frequency
λ = v/f
λ = 3×10⁸m/s/2.8 x 10³ Hertz
λ = 107 nm
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In clinical applications, the unit parts per million (ppm) is used to express very small concentrations of solute, where 1 ppm is equivalent to 1 mg of solute per 1 L of solution. Calculate the concentration in parts per million for each of the solutions.There is 43 μg of calcium in a total volume of 87 mL .concentration of calcium: _________ppm There is 0.91 mg of caffeine in a total volume of 105 mL .concentration of caffeine: _________ppm There is 0.47 mg of trace particles in a total volume of 95 dL .concentration of trace particles: ___________
Answer & Procedure
To solve this problem you will need to transform all the concentrations to the equivalence of ppm, which is 1 mg of solute per 1 L of solution.
Calcium: There are 43 μg of calcium in a total volume of 87 mL.
[tex]\frac{43\mu g}{87\text{ mL}}\frac{1\text{ mg}}{1000\text{ }\mu g}\frac{1000\text{ mL}}{1\text{ L}}=0.49\frac{mg}{L}=0.49\text{ ppm}[/tex]Caffeine: There is 0.91 mg of caffeine in a total volume of 105 mL.
[tex]\frac{0.91\text{ mg}}{105\text{ mL}}\frac{1000\text{ mL}}{1\text{ L}}=8.67\frac{mg}{L}=\text{ 8.67 ppm}[/tex]Trace particles: There is 0.47 mg of trace particles in a total volume of 95 dL.
[tex]\frac{0.47\text{ mg}}{95\text{ dL}}\frac{10\text{ dL}}{1\text{ L}}=0.049\frac{mg}{L}=0.049\text{ ppm}[/tex]According to the beer-lambert law, what happens to the absorbance value of a light-absorbing chemical when its concentration increases?.
According to the beer-lambert law when its concentration increases so does the absorbance increase.
beer-lambert law states that the amount of energy absorbed or transferred by a solution is proportional to the molar absorptivity of the solution and the concentration of the solute.
This means that concentrated solutions absorb more light than dilute solutions.
so the According to the beer-lambert law concentration increases, so does the absorbance. Therefore, absorbance is directly proportional to concentration.
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A cycling has a radius of 2.63 cm and a height of 1.72 cm a) Calculate the volume of the cylinder b) if the cylinder weight 78.53g, calculate its density and specific gravity.
The volume of a cylinder is calculated using the following formula:
[tex]V=\pi\times r^2\times h[/tex]Where r is teh radius of the base and h is the high:
[tex]V=\pi\times(2.63\operatorname{cm})^2\times1.72cm=37.37cm^3[/tex]As we know 1cm³=1ml
to calculate the density we just have to divide the mass by the calculated volume:
[tex]\text{density}=\frac{78.53g}{37.37ml}=\text{ }2.10\text{ }\frac{g}{ml}[/tex]The especific gravity is the density in relation to the density of water which is 1 g/ml therefore:
[tex]\text{specific gravity =}\frac{density}{water\text{ density}}=\frac{2,10g/ml}{1g/ml}=\text{ 2.1}[/tex]A 200g piece of iron absorbs 8980 joules to raise the temperature from 20°C to 120°C. Find the specific heat of iron?
Answer:
The specific heat of iron is 0.449 J/g°C.
Explanation:
First, let's see the formula of specific heat:
[tex]c=\frac{q}{m\cdot\Delta T}\begin{cases}{q=amount\text{ of heat \lparen Joules\rparen}} \\ {m\text{ = mass of substance \lparen grams\rparen}} \\ \Delta T={Change\text{ of temperature \lparen\degree C\rparen}}\end{cases},[/tex]Now, we have to replace the given data in the formula, where q = 8980 J, m = 200 g and ΔT = Final temperature - Initial temperature = 120 °C - 20 °C = 100 °C:
[tex]c=\frac{8980\text{ J}}{200\text{ g}\cdot100\degree C}=0.449\frac{J}{g\degree C}.[/tex]The specific heat of iron is 0.449 J/g°C.
The frequency of a wave is 2.80 x 10^18 Hertz. Find the wavelength and energy of this wave.
Show all work!
The frequency of a wave is 2.80 × 10¹⁸ Hertz. The wavelength is 0.10 nm and energy of this wave is 2.80 × 10¹⁸ .
Given that :
The frequency of a wave, v = 2.80 × 10¹⁸ Hz
wavelength = ?
formula for the wavelength is given as follows :
λ = c/ v
c = speed of light
λ = 3 × 10⁸ m/s / 2.80 × 10¹⁸ s⁻¹
λ = 1.07 × 10⁻¹⁰ = 0.10 nm
Energy of wave = h v
h = planks constant
E = 6.626 × 10⁻³⁴ J.s × 2.80 × 10¹⁸ s⁻¹
E = 18.55 × 10 ⁻¹⁶ J
Thus, The frequency of a wave is 2.80 × 10¹⁸ Hertz. The wavelength is 0.10 nm and energy of this wave is 2.80 × 10¹⁸ .
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how many sodiums and how many phosphorus ions are needed to form an ionic compound, what is the name of the compound?
Two sodium ions and one phosphate ion are needed to form an ionic compound named sodium phosphate [tex]Na_{3}PO_{4}[/tex].
These two polyatomic ions require opposite charges that are both equivalent to form a bond. As a result, the one -3 phosphate ion needs to be balanced by three +1 sodium ions.
What is ionic compound?A chemical compound known as an ionic compound in chemistry is one that contains ions held together by the electrostatic forces known as ionic bonding. Despite having both positively and negatively charged ions, or cations and anions, the compound is overall neutral.
Thus in sodium phosphate sodium is the cation and phosphate is the anionic.
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An orange solid cannot be broken down into simpler components by any physical methods. When it is heated, a chemical reaction takes place and a colorless gas and a silvery liquid form. Further tests on the resulting substances shows that they cannot be broken down further by physical or chemical methods. What type of substance is the original orange solid?.
Physically or chemically, elements cannot be reduced farther since they are the most basic form of matter. A pure substance known as an element is one that has only one sort of atom.
their nuclear numbers of protons. The debate over the conceptual meaning of the word "element" offers a rather singular chance to look at how chemists currently relate to one atom.
A chemical approach is one that aims to alter the chemical make-up of the waste's constituent elements. Using 1 papers, Sample 1 Examples of using the chemical technique in a phrase In the chemical atom used in wastewater treatment, pollutants are taken out of the wastewater and released through discharge outlets.
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How many joules of heat are needed to completely vaporize 24.40 grams of water at its boiling point?Given ΔHvap = 40.6 kJ/mol
55,035.5 Joules
Explanations:Heat of vaporisation is the amount of energy required to transform a mole of liquid water into gas at constant temperature.
Given the following parameters:
Mass of water = 24.40 grams
ΔHvap = 40.6 kJ/mol
Determine the moles of water
Mole = mass/molar mass
Mole = 24.40/18
Mole of water = 1.356moles
Determine the required heat required
Q = mole of water * ΔHvap
Q = 1.356moles * 40.6kJ/mole
Q = 55.0355kJ
Q = 55.0355 * 1000
Q = 55,035.5 Joules
Hence joules of heat needed to completely vaporise 24.40 grams of water at its boiling point is 55,035.5 Joules
7. Calculate the percent compositions for each element in:
a. calcium fluoride, CaF₂
b. magnesium nitride, Mg N
c. cadmium perchlorate, Cd(CIO4)2
2. You were asked to examine a prepared slide under the HPO. Your eyepiece is 20x and the HPO is 80x. How many times was the specimen magnified?
Answer:
Explanation:
Magnification = 20 * 80
1600
Consider a galvanic cell with a beaker of sulfuric acid and a beaker of nitric acid. The sulfuric acid beaker contains a strip of tin, and the nitric acid cell contains a strip of platinum. A wire runs between the strips. The reaction that occurs is as follows: 3Sn(s) + 2NO_3^–(aq) + 8H^+(aq) → 3Sn_2+(aq) + 2NO(g) + 4H_2O(l). Which electrode is the anode? (1 pt)
*
1 point
tin
platimun
Consider a galvanic cell with a beaker of sulfuric acid and a beaker of nitric acid the sulfuric acid beaker contains a strip of tin, and the nitric acid cell contains a strip of platinum a wire runs between the strips then tin is the anode
Galvanic cell is the electrochemical cell that converts the chemical energy of spontaneous redox reactions into electrical energy
Here given data is galvanic cell with a beaker of sulfuric acid and a beaker of nitric acid the sulfuric acid beaker contains a strip of tin, and the nitric acid cell contains a strip of platinum a wire runs between the strips and the reaction is
3Sn(s) + 2NO₃⁻(aq) + 8H⁺(aq) → 3Sn²⁺(aq) + 2NO(g) + 4H₂O(l)
Then in the galvanic cell oxidation takes place at the anode means the tin is the anode
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complete the fission reaction.235U + 1 neutron → [X] +141Ba + 3 neutronsMass Number:Chemical Symbol:
It's important to know that the reaction must have the total mass involved before and after due to the law of conservation of mass. This means that the total mass number of the left side of the reaction must be equal to the right side. So, we have the following
[tex]235+1=X+141+3[/tex]Notice that 235 is the mass number of U, 1 is the mass number of the neutron, X represents the mass number of the unknown element, 141 represents the mass number of Ba, and 3 represents the mass number of three neutrons. This means X should have a mass number of 92, which is the element Kr.
Therefore, the mass number is 92 and the chemical symbol is Kr.
What type of mechanical mixture is pop
there are moles in 9.01 x 10^23 molecule in water
There are 1.5 moles of water present.
What is the number of moles?We know that according to the work of Avogadro, the number of moles of the water molecule can be obtained. According to his work, one mole of the water molecule can be able to have about 6.02* 10^23 molecules of water. This is thus the number of molecules in one mole of water and it can be used to obtain the number of moles of water at any point.
If 1 mole of water contains 6.02* 10^23 molecules of water
x moles of water contains 9.01 x 10^23 molecule of water
x = 9.01 x 10^23 molecule * 1 mole/ 6.02* 10^23 molecules
x = 1.5 moles
Thus we can see that the number of moles of water that is present is 1.5 moles in the 9.01 x 10^23 molecules of water present here.
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3.Look at the positions of calcium, beryllium, and magnesium on the periodic table. Based on their locations, predict how many valence electrons these elements have and predict what the reactivity of these elements will generally be.
Answer:
They have two valence electrons and enter into reactions where they can donate their two valence electrons
Explanation:
Here, we want to predict the number of valence electrons
The elements belong to the group 2 of the periodic table
Elements in the periodic table are placed in groups based on the number of valence electrons they have
It is expected that elements in group 2 of the periodic table have 2 valence electrons
Their reactivity is that, they react with other atoms by donating this two valence electrons. They then achieve the electronic configuration of the noble gas in the last period