Hello. You forgot to say that this question is about the possibility of using some type of product that prevents cut apples from becoming darker.
Answer and Explanation:
1. The problem with this activity is "What can you put on an apple slice to keep it from turning brown?" The problem in a scientific experiment is the element that provides a question about what is being observed.
2. Hypotheses are assumptions made about what was observed, in addition, hypotheses can answer the question shown in the problem. In the case of apples, the hypotheses can be: "Lemon juice is the most efficient product in delaying the blackening of cut apples." "Water is inefficient in preventing blackened cut apples." "Milk accelerates the blackness of cut apples."
3. The dependent viable is one that needs to be influenced by another element to bring about a result. In the case of the experiment with apples, the dependent variable is the blackening rate of the apple slices.
4. The independent variable, on the other hand, refers to the element that does not need any influence to cause a result, on the contrary, this variable acts on the dependent variable, influencing it. In the case of this experiment, the independent variable is the types of liquid tested to delay the blackening of cut apples.
5. Lemon was the most efficient liquid. Probably this efficiency is related to the lemon's ability to decrease the strength of antioxidants, due to its very low pH.
2-Methycyclohexanol is prepared commercially by catalytic hydrogenation of ocresol (2-methylphenol) and consists of a mixture of cis and trans isomers. (Note the spectrum is for the mixture.) (Hint: What do the peaks at 3.05 ppm and 3.75 ppm represent and what does their integration show
Answer:
Explanation:
From the information given :
The cis and trans isomer are in the ratio of 1:3, and the description of how the ratio of the cis- and trans-2-methylcyclohexanols from the 1H NMR spectrum can be explained as follows:
We are being told that the trans isomer's peak is 3.75 ppm (part per million). However, because the methyl group is far away from the OH group, it is less shilled than the cis isomer, which peaked at 3.05. Thus, the peak at 3.05 occurs in an area whose integration is three (3) times more than the peak at 3.75.
Element
Molar mass (g/mol)
1.008
H
С
12.01
16.00
Using the information in the table, calculate the number of moles in a 2.03 kg sample of citric acid
(C6H8O7)
Write your answer using three significant figures.
mol C6H8O7-
Answer:
Number of moles = 10.6 mol
Explanation:
Given data:
Molar mass of H = 1.008 g/mol
Molar mass of C = 12.01 g/mol
Molar mass of O = 16.00 g/mol
Mass of citric acid = 2.03 kg (2.03×1000 = 2030 g)
Number of moles of citric acid = ?
Solution:
Formula:
Number of moles = mass/molar mass
Now we will calculate the molar mass of citric acid:
C₆H₈O₇ = (12.01× 6) + (1.008×8) + (16.00×7)
C₆H₈O₇ = 72.06 + 8.064+112
C₆H₈O₇ = 192.124g/mol
Number of moles = 2030 g/ 192.124g/mol
Number of moles = 10.6 mol
The number of moles in a 2.03 kg sample of citric acid is :
- 10.6 mol
Molar MassGiven:
Molar mass of H = 1.008 g/mol
Molar mass of C = 12.01 g/mol
Molar mass of O = 16.00 g/mol
Mass of citric acid = 2.03 kg (2.03×1000 = 2030 g)
Number of moles of citric acid = ?
Formula:
Number of moles = mass/molar mass
The molar mass of citric acid:
C₆H₈O₇ = (12.01× 6) + (1.008×8) + (16.00×7)
C₆H₈O₇ = 72.06 + 8.064+112
C₆H₈O₇ = 192.124g/mol
Number of moles = 2030 g/ 192.124g/mol
Number of moles = 10.6 mol
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Name the following ionic compound: Ba(OH)2*2H2O
Metals typically lose electrons to complete their octet in a reaction with non-metals, whereas non-metals typically acquire electrons to complete their octet. Ionic compounds are typically formed via reactions between metals and nonmetals. The given compound barium hydroxide is ionic.
Ions with the opposite charge are carefully packed together to form crystalline solids. Ionic compounds typically result from reactions between metals and non-metals. The electrostatic interaction between the positive and negative ions holds ionic solids together.
Baryta, commonly known as barium hydroxide, has the chemical formula Ba(OH)₂. It is an odorless, clear-white powder. It has a toxic disposition. It is ionic in nature, with two hydroxide ions per molecule of barium hydroxide (Ba(OH)₂ in an aqueous solution an example.
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Complete the reactions of Sn(II) and Sn(IV), and be sure that the reactions are balanced. Do not include the phases (liquid, aqueous, etc.). If no reaction occurs, leave the products side of the equation
completed reaction: SnBr2+PbBr4⟶
completed reaction: SnBr4+PbBr2⟶
Select the statements that are true about the reactions.
A. PbBr4 is more stable than PbBr2.
B. The inert‑pair effect renders Sn(II) as the more stable oxidation state of tin.
C. Sn(IV) is the most stable oxidation state of tin.
D. The inert‑pair effect renders Pb(II) as the more stable oxidation state of lead.
Answer:
The Inert Pair effect renders Pb(II) as the more stable oxidation state of lead
Explanation:
SnBr4 + PbBr2 ---> SnBr2 + PbBr4
SnBr2 + PbBr4 ---->
The Inert pair effect is mostly observed between group 15-17 in the periodic table. It leads to stability of the lower oxidation state of an element.
The reason for the Inert pair effect is that the s electrons become Inert due to poor shielding of the d and f-electrons. The Inert pair effect is a tendency of the s electrons not to participate in bonding (remain an Inert pair).
Owing to the Inert pair effect, Pb II is more stable than Pb IV
How many moles of precipitate will be formed when 100.0 mL of 0.200 M NaBr is reacted with excess Pb(NO₃)₂ in the following chemical reaction?
2 NaBr (aq) + Pb(NO₃)₂ (aq) → PbBr₂ (s) + 2 NaNO₃ (aq)
Answer : The number of moles of precipitate, [tex]PbBr_2[/tex] formed will be 0.01 moles.
Explanation : Given,
Concentration of NaBr = 0.200 M
Volume of solution = 100.0 mL = 0.1 L (1 L = 1000 mL)
First we have to calculate the moles of NaBr.
[tex]\text{Moles of NaBr}=\text{Concentration of NaBr}\times \text{Volume of solution in L}[/tex]
[tex]\text{Moles of NaBr}=0.200M\times 0.1L=0.02mol[/tex]
Now we have to calculate the moles of precipitate, [tex]PbBr_2[/tex] formed.
The balanced chemical reaction is:
[tex]2NaBr(aq)+Pb(NO_3)_2(aq)\rightarrow PbBr_2(s)+2NaNO_3(aq)[/tex]
From the balanced chemical reaction we conclude that:
As, 2 moles of NaBr react to give 1 mole of [tex]PbBr_2[/tex]
So, 0.02 moles of NaBr react to give [tex]\frac{0.02}{2}=0.01[/tex] mole of [tex]PbBr_2[/tex]
Therefore, the number of moles of precipitate, [tex]PbBr_2[/tex] formed will be 0.01 moles.
The number of mole of the precipitate (i.e PbBr₂) formed when 100 mL of 0.2 M NaBr react with excess Pb(NO₃)₂ is 0.01 mole
We'll begin by calculating the number of mole of NaBr in 100 mL of 0.2 M NaBr solution. This can be obtained as follow:Volume = 100 mL = 100 / 1000 = 0.1 L
Molarity of NaBr = 0.2 M
Mole of NaBr =?Mole = Molarity x Volume
Mole of NaBr = 0.2 × 0.1
Mole of NaBr = 0.02 mole Finally, we shall determine the number of mole of the precipitate (i.e PbBr₂) produced from the reaction. This can be obtained as follow:2NaBr(aq) + Pb(NO₃)₂(aq) → PbBr₂(s) + 2NaNO₃ (aq)
From the balanced equation above,
2 moles of NaBr reacted to produce 1 mole of PbBr₂.
Therefore,
0.02 mole of NaBr will react to produce = [tex]\frac{0.02}{2} \\\\[/tex] = 0.01 mole of PbBr₂.
Thus, the number of mole of the precipitate (i.e PbBr₂) produced from the reaction is 0.01 mole
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Select the term that matches each definition:
a) A decrease in the solubility of an ionic compound as a result of the addition of a common ion.
b) The mass of a salt in grams that will dissolve in 100 mL of water.
c) A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved.
d) The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation.
e) The maximum number of moles of a salt that will dissolve in 1 L of solution.
*** Answer options for all questions: ***
- Solubility
- Molar Solubility
- Solubility product constant
- Common ion effect
- Saturated Solution
Answer: a) A decrease in the solubility of an ionic compound as a result of the addition of a common ion : Common ion effect
b) The mass of a salt in grams that will dissolve in 100 mL of water: Solubility
c) A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved: Saturated solution
d) The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation : Solubility product constant
e) The maximum number of moles of a salt that will dissolve in 1 L of solution : Molar solubility
Explanation:
Solubility is expressed usually as the mass of solute per 100 grams or 100 ml of solvent.
Molar solubility of a solid is expressed as the concentration of the dissolved solid in a saturated solution.
Solubility product constant is defined as the equilibrium constant in which a solid ionic compound is dissolved to produce its ions in solution. It is represented as [tex]K_{sp}[/tex]
The common-ion effect is the decrease in solubility of a sparingly soluble salt by the addition to the solution of a soluble compound with an ion in common with the precipitate.
Saturated solution is defined as the solution in which no more solute particles can be dissolved in the solvent.
What is the density of a block of gold that occupies 1000 ml and has a mass of 3.5 kg? Show your work
Answer:
Density of block of gold is 3.5 g/cm³.
Explanation:
Given data:
Volume of block = 1000 mL
Mass of block = 3.5 kg (3.5×1000 = 3500 g)
Density of block = ?
Solution:
Density of substance is calculated by dividing the mass of substance over its volume.
Formula:
d = m/v
d = 3500 g/ 1000 mL
d = 3.5 g/mL
or
d = 3.5 g/cm³ (1ml = 1cm³)
What is a chelating agent?
Answer:
Chelation is a type of bonding of ions and molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate ligand and a single central atom. These ligands are called chelants, chelators, chelating agents, or sequestering agents.
Answer:
Chemical compound that react with metal ions. They can form several covalent bonds to a metal without changing its own structure.
Explanation:
There's a list of chelating agents you can find in your book probably. An application of chelating agents is to transport metal ions across the membranes.
you should also know:
Chelating agents are any compound that reacts with a metal ion to produce a metal ion.
Ligand ion molecule or functional group that binds to another chemical to make a larger complex.
They are used to detoxify poisonous metal agents by binding and converting them so the body can excrete them without further harm.
The energy associated with the motion and position of an object is called a.kinetic energy
b.potential energy
c.gravitational potential energy d.mechanical energy
Answer: The answer is D.
Explanation:
The form of energy associated with the motion, position, or shape of an object is called mechanical energy. An object's mechanical energy is a combination of its potential energy and its kinetic energy. The basketball has both potential energy and kinetic energy.
Hope this helps!
Which statement best demonstrates how data from a global positioning system (GPS) can be used to lessen the effects of a
wildfire? (1 point)
GPS data can be used by people to quickly evacuate an area because of a wildfire
GPS data can be used by scientists to predict weather patterns that can lead to a wildfire
GPS data can be used by firefighters to identify the boundaries of a wildfire
GPS data can be used by first responders to calculate the safest route to a wildfire
Answer: here is your answer
Explanation: You are visiting your Grandmother and notice that she is eating a balanced diet, taking vitamins, getting the proper amount of sleep and is not overweight. Despite her healthy lifestyle, she appears run down and tired. You realize that it's due to her lack of physical activity. Write a convincing letter to your grandma explaining the benefits of participating in regular physical activity.
A teaspoon of salt, NaCl has a mass of about
5.0 g. How many formula units are in a
teaspoon of salt?
Answer: The answer is 5.15x10^22
Explanation:
The formula unit present in a teaspoon of salt [tex]NaCl[/tex] having a mass of about 5.0 g is [tex]5.15 \times10^{22}[/tex] formula units.
Molar mass, also known as molecular weight, is the mass of one mole of a substance. It is calculated by summing up the atomic masses of all the atoms in a molecule. The unit of molar mass is grams per mole (g/mol).
Now, to determine the number of formula units in a teaspoon of salt (NaCl), we need to use Avogadro's number and the molar mass of NaCl.
Avogadro's number [tex](N_a)[/tex] is approximately. [tex]6.022 \times10^{23}[/tex] formula units per mole.
The molar mass of [tex]NaCl[/tex] is the sum of the atomic masses of sodium (Na) and chlorine ([tex]Cl[/tex]), which are approximately 22.99 g/mol and 35.45 g/mol, respectively.
To calculate the number of formula units in 5.0 g of [tex]NaCl[/tex], we can follow these steps:
Now, calculate the number of moles of [tex]NaCl[/tex] using its molar mass:
Moles = Mass / Molar mass
Moles = [tex]5.0 g[/tex] / [tex](22.99 g/mol + 35.45 g/mol)[/tex]
Calculate the number of formula units using Avogadro's number:
Formula units = [tex]Moles \times Avogadro's number[/tex]
Let's perform the calculation:
Molar mass of [tex]NaCl[/tex]= [tex]22.99 g/mol + 35.45 g/mol = 58.44 g/mol[/tex]
Moles of [tex]NaCl[/tex] = [tex]5.0 g[/tex] / [tex]58.44 g/mol[/tex] ≈ [tex]0.0856 mol[/tex]
Formula units = [tex]0.0856 mol \times (6.022 \times 10^{23})[/tex] formula units/mol ≈ [tex]5.15 \times10^{22}[/tex]formula units.
Therefore, there are approximately [tex]5.15 \times10^{22}[/tex] formula units in a teaspoon of salt ([tex]NaCl[/tex]) having mass [tex]5.0 g[/tex].
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Please help me!!!:)))
Answer:
blocks 1 and 2 the rhdh huff hgfhh5
A substance that is dissolved in a solution is called a(n) __________________.
solute
compound
ion
Answer:
solute
Explanation:
The smallest form of matter that still retains the properties of an element
Answer:
atom
Explanation:
the atom is the smallest form.
How many elements are in calcium dihydrogren phosphate
What is the pH of a bleach solution that has a [OH−]=1.3×10−4 M?
Answer:
pH = 10.113
Explanation:
Here, we can find pOH first:
pOH = [tex]-log([OH^-])[/tex] = 3.886.
Then, we can find pH which is 14 - pOH. We then get the answer above.
Then, we can find pH which is 14 - pOH. We then get the answer above.
The pH of acid is between 0-7 on pH scale while for base pH range is from 7-14. Thus the pH of 1.3×10⁻⁴ M bleach solution is 10.62.
What is pH?pH is a measurement of amount of hydronium ion H₃O⁺ in a given sample. More the value of hydronium ion concentration, more will be the solution acidic.
On subtracting pH from 14, we get pOH which measures the concentration of hydroxide ion in a given solution. pH depend on the temperature. At room temperature pH scale is between 0 to 14. pH of neutral solution is 7
The concentration of bleach solution is 1.3×10⁻⁴ M
Concentration of OH⁻=1.3×10⁻⁴ M
Mathematically,
pOH=-log[OH⁻]
Substituting the values
pH=-log[1.3×10⁻⁴]
= 3.886.
pH+ POH=14
pH=14-3.886.=10.62
Therefore, the pH of 1.3×10⁻⁴ M bleach solution is 10.62.
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What processes are related to metamorphism
Answer:
Metamorphism is the change of minerals or geologic texture (distinct arrangement of minerals) in pre-existing rocks (protoliths), without the protolith melting into liquid magma (a solid-state change). The change occurs primarily due to heat, pressure, and the introduction of chemically active fluids.
Explanation:
i hope this helps :)
Given the volume of a gas at 200mL at 1.05atm pressure, calculate the volume of the same gas at 1.01atm. The temperature is held constant.
Answer:
The new pressure will be
1000 L
, rounded to one significant figure.
Explanation:
Boyle's law states that when a gas is held at a constant temperature and mass in a closed container, the volume and pressure vary inversely. The equation to use is
P
1
V
1
=
P
2
V
2
.
Given
V
1
=
200
mL
×
1
L
1000
mL
=
0.2 L
P
1
=
700 mmHg
V
2
=
100
mL
×
1
L
1000
mL
=
0.1 L
Unknown
P
2
Equation
P
1
V
1
=
P
2
V
2
Solution
Rearrange the equation to isolate
P
2
and solve.
P
2
=
P
1
V
1
V
2
P
2
=
(
700
mmHg
×
0.2
L
)
0.1
L
=
1400 L
, which must be rounded to
1000 L
because all of the measurements have only one significant figure
Explanation:
Choose all the answers that apply.
Fluorine (F) has seven electrons in its outermost shell. Fluorine _____.
-is a metal
-fills its shell by giving up seven electrons
-fills its shell by gaining one electron
-becomes a positively charged ion
-becomes a negatively charged ion
-is a nonmetal
Answer:
Fluorine is a non-metal, fills its shell by gaining one electron and becomes a negatively charged ion.
Explanation:
Fluorine have seven electrons in its outermost shell. This means that fluorine is located in Group 17(Halogens) in the Periodic Table. Note that halogens are non-metal elements. So fluorine is a non-metal.
Fluorine fills its shell by gaining one electron because it only needs one electron to achieve stable octet electron arrangement. ( it's easier to gain one electron than to lose all seven electrons in the outermost shell)
As fluorine atom gain one electron to achieve stable octet electron arrangement, its number of electrons becomes greater than its number of protons. So it becomes a negatively charged ion.
What types of materials are better at absorbing energy from radiation?
Answer:
Explanation:
Materials are clothes and heavy rope
Is a diamond a homogeneous or heterogeneous mixture?
Answer:
It's a heterogeneous mixture.
Explanation:
Diamond is made of just one element: carbon. Each carbon atom in diamond is connected to four other carbon atoms, in a crystal that extends on and on. There are other forms of pure carbon where the atoms are bonded differently, notably charcoal and graphite.
Answer:
It's a heterogeneous mixture.
Explanation:
Diamond is made of just one element: carbon.
How would you calculate an object's mechanical energy?
a. Add its kinetic and potential energies. b. Multiply its kinetic and potential energies.
c. Subtract its kinetic energy from its kinetic energy.
d. Subtract its potential energy from its kinetic energy.
Answer:
You would add its kinetic and potential energies.
Explanation:
Hope this helps!! :)
Answer:
A) Add its kinetic and potential energies
Explanation:
I got it right on Edge 2022
Which is NOT an example of plants demonstrating the characteristics of life?
A. Plants are forces to make adaptations depending on its environment
B. A plant has stimuli that cause it to grow towards the sun
C. There are stages of growth that plants go through depending on favorable conditions
D. The leaves on a plant move in reaction to the wind
Answer:
D
Explanation:
trust me bro ive done this
Option D does not represent an example of plants demonstrating the characteristics of life.
The following information should be considered:
Plants to be treated as the forces for making the adaptions and based on the environment. The plant contains stimuli that result to grow towards the sun. There should be the growth stages based on the favorable conditions.Therefore we can conclude that Option D does not represent an example of plants demonstrating the characteristics of life.
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Calculate the theoretical density (in g/cm3) of copper (Cu), given that it has the FCC structure. The atomic weight of Cu is 63.55 g/mol, and its atomic radius R is 0.1278 nm.
Answer:
8.937g/cm³
Explanation:
To answer this question we need to know that, in 1 unit FCC cell you have:
Edge length = √8 * R
Volume = 8√8 * R³
And there are 4 atoms per unit cell
Mass of 4 atoms in g:
4 atom * (1mol / 6.022x10²³atom) * (63.55g / mol) = 4.221x10⁻²²g
Volume in cm³:
0.1278nm * (1x10⁻⁷cm / 1nm) = 1.278x10⁻⁸cm
Volume = 8√8 * (1.278x10⁻⁸cm)³
Volume = 4.723x10⁻²³cm³
And density is:
4.221x10⁻²²g / 4.723x10⁻²³cm³ =
8.937g/cm³Please help with number 7 thank you! 30 points
Answer:
X indicates proteins Y indicates lipids
Explanation:
X shows membrane bound proteins. Y shows lipids in the plasma membrane.
Answer:
I think that x indicates proteins and y indicates lipids
Explanation:
Proteins often are channels that help things get in and out of the cell, and x looks like one.
Membranes are made of phospholipids, which are types of lipids. Y is a lipid.
A student throws a 0.46kg bowling ball at a velocity of 25m/s what is the kinetic energy of the bowling ball in Joules
Answer:
The answer is 143.57 JExplanation:
The kinetic energy of an object can be found by using the formula
[tex]KE = \frac{1}{2} m {v}^{2} \\ [/tex]
where
m is the mass
v is the velocity
From the question we have
[tex]KE = \frac{1}{2} \times 0.46 \times {25}^{2} \\ = 0.23 \times 625[/tex]
We have the final answer as
143.75 JHope this helps you
1. Consider the following: HCl (aq) + NaOH (aq) → NaCl (aq) + H2O (liq) ∆H = -57.62 kJ/mol
If a 25.0 mL of 0.144 M HCl (aq) at 25oC is added to 20.0 mL of 0.132 M NaOH (aq) at 25oC, calculate the final temperature of the contents. Assume the volumes are additive and that the resulting salt water solution has a density of 1.04 g/mL with a specific heat capacity of 3.93 J/goC. Note that you will also need to determine the limiting reactant.
Answer:
25.82°C
Explanation:
Based on the reaction, 1 mole of HCl and 1 mole of NaOH reacts, that means the reaction is 1:1. The moles of each compound are:
Moles HCl:
0.025L * (0.144mol/L) = 0.0036 moles HCl
Moles NaOH:
0.020L * (0.132mol/L) = 0.00264 moles NaOH
Thus, moles of reaction are 0.00264 moles
The heat released in a calorimeter is obtained using the equation:
Q = m*c*ΔT
Where Q is heat released in the reaction:
0.00264 moles * (-57.62kJ/mol) = 0.1521kJ = 152.1J of reaction
m is mass of the solution:
25.0mL + 20.0mL = 45mL * (1.04g/mL) = 46.8g
c is specific heat of the solution:
3.93J/gºC
And ΔT is change in temperature.
Solving for ΔT:
Q /mc = ΔT
151.2J / 46.8g*3.93J°C = 0.82°C = ΔT = Final temperature - Initial temperature.
Final temperature = 0.82°C + 25°C =
25.82°C
4. This is low wet land.
A. swamp
B. island
C. desert
D. peninsula
5. Japan is one of these.
A. island
B. peninsula
C. swamp
D. desert
Answer:
swap
Explanation: because it is a low wet land
Answer:
4. swamp
5. Island
Plz mark brainliest:)
When solid Fe metal is put into an aqueous solution of SnSO4, solid Sn metal and a solution of FeSO4 result. Write the net ionic equation for the reaction.
Answer:Fe(s) + Sn^2+(aq) ----> Fe^2+(aq) + Sn(s)
Explanation:
The net ionic equation involved is;
Fe(s) + Sn^2+(aq) ----> Fe^2+(aq) + Sn(s)
We must recall that iron is above tin in the electrochemical series. The implication of this is that, iron has a more negative reduction potential compared to tin.
A metal can displace metals below it in the electrochemical series from their aqeous solution. Hence, iron displaces tin from it's solution.
The table below shows first ionization energies of some of the elements in the periodic table.Based on the information in the table, what can you conclude about the ability of noble gases to undergo ionization?
a
Noble gases give up first electrons easily compared to elements in other groups.
b
Noble gases cannot be forced to give up electrons.
c
The willingness of a noble gas to give up electrons decreases from top to bottom within the group.
d
It is more difficult to remove electrons from a noble gas than it is to remove electrons from elements in other groups.
Answer:
It is more difficult to remove electrons from a noble gas than it is to remove electrons from elements in other groups.
Explanation:
Let me restate here that in the noble gases, the outermost shell is filled. Owing to this full shell, noble gases has the outermost eight electrons required for any specie to attain stability.
It is very difficult to remove an electron from a closed shell. This is why the first ionization energy of noble gases is usually far higher than that of elements from other groups.