This molecule will have dipole-dipole forces.
Answer: B
How would I convert 246.44 L of gasoline into kilograms? The density of gasoline is 0.800 kg/L
The density is defined like:
Density = mass / volume
We know the volume of gasoline and the density. Using that formula we can find the mass that is our unknown.
mass of gasoline = ?
density of gasoline = 0.800 kg/L
volume of gasoline = 246.44 L
Density = mass/volume
mass = volume * density
mass = 246.44 L * 0.800 kg/L
mass = 197.2 kg
Answer: we have 197.2 kg in 246.44 L of gasoline.
Rachel burns a 53 gram cracker under a soda can filled with 77.8 grams of water. She took the temperature of the water before she began -- it was 9.3 degrees Celsius. After the cracker was done burning, the temperature of the water was 73.8 degrees Celsius. How many calories of heat were released by the cracker? Round your answer to one digit after the decimal point.
In this question, we have a situation in which we have to use the Calorimetry formula, which is how much heat was released or absorbed (in Joules), after we had a change in temperature of a compound. The formula for this Calorimetry question is:
Q = mcΔT
Where:
Q = is energy as Heat
m = mass in grams, 77.8 grams
c = is the specific heat capacity, 4.184 J/g°C this is for water
ΔT = the change in temperature, calculated as Final Temperature - Initial T
73.8 - 9.3 = 64.5°C
It is important to know that the heat released by the cracker is the same heat absorbed by water but with an opposite mathematical sign, so we have to find out the heat absorbed by water:
Q = 77.8 * 4.184 * 64.5
Q = 20995.7 J is the heat absorbed by water
Therefore the heat released by the cracker is - 20,995.7 J
Determine the volume (mL) required to prepare each of the following. 190 mL of a 0.300 M HNO3 solution from a 3.75 M HNO3 solution.Express your answer with the appropriate units.
To solve this problem we have to use the rule of dilutions:
[tex]V1\cdot C1=V2\cdot C2[/tex]Where V1 is the initial volume, C1 is the initial concentration, V2 is the final volume and C2 is the final concentration.
In this case, we need to find V1. Solve the equation for V1 and then replace C1 for 3.75M, V2 for 190mL and C2 for 0.300M:
[tex]\begin{gathered} V1=\frac{V2\cdot C2}{C1} \\ V1=\frac{190mL\cdot0.300M}{3.75M} \\ V1=15.2mL \end{gathered}[/tex]It means that the volume required is 15.2mL.
REACTION; C5H12 + 8O2 5CO2 + 6H2OWhen 15.5 grams of C5H12 are consumed in this reaction what volume of CO2 can be produced in liters?
Step 1 - Finding the stoichiometry of the reaction
The given reaction is:
[tex]C_5H_{12}+8O_2\to5CO_2+6H_2O[/tex]To find the stoichiometry of the reaction in moles, we just have to "read" the bigger numbers that come before the formulas of the substances:
1 mole of C5H12 reacts with 8 moles of O2 thus producing 5 moles of CO2 and 6 moles of H2O
Since the exercise is specifically asking us about the relation between C5H12 and CO2, we can simplify this statement to:
1 mole of C5H12 produces 5 moles of CO2
Step 2 - Converting this relation to a relation in grams
To convert moles to grams, we just need to multiply the number of moles by the molar mass of the substance.
Since the exercise is giving us the mass of C5H12, it would be interesting to convert its number of moles to mass (its molar mass is 72 g/mol):
[tex]C_5H_{12}\to1\times72=72g[/tex]We can now rewrite the statement in step 1 as:
72g of C5H12 produce 5 moles of CO2
Step 3 - Finding how many moles of CO2 will be formed
To find the moles of CO2 that will be formed, we can set the following proportion:
[tex]\begin{gathered} 72g\text{ of C5H12 produce ---- 5 moles of CO2} \\ 15.5g\text{ of C5H12 would produce --x } \\ \\ x=\frac{15.5\times5}{72}=1.07\text{ moles of CO2} \end{gathered}[/tex]Step 4 - Converting moles to volume
The molar volume of a gas in STP conditions (standard pressure and volume) is 22.4 L/mol, which means that each mole of gas occupies 1 L. Since we have formed 1.07 moles of CO2, we have:
[tex]V=1.07\times22.4=23.96L[/tex]The volume of CO2 that would be formed is thus 23.96L.
6. How is a magnet turned into a temporary magnet?
A. It has to contain hydrocarbons
B. It has to be pure iron
C. It has to have opposite magnetic poles
D. It has to have an alloy of iron
A magnet turned into a temporary magnet is It has to have opposite magnetic poles. Option C.
Temporary magnets are made of soft metals that become magnetized only when exposed to a permanent magnetic field or electric current. When they come into contact with a magnetic field, they become magnetized. Temporary magnets are made of soft metals that retain their magnetism only when in proximity to a permanent magnetic field or electric current.
They are magnetized in the presence of a magnetic field. Clips, iron nails, and other similar items are examples of temporary magnets. The force that a magnet exerts on a particular substance, including other magnets, is called magnetic force. Forces act over distance and include attraction and repulsion. The north and south poles of two magnets attract each other but the two north poles or the two south poles repel each other.
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Calculation: If a compound is 14.40% hydrogen by mass and 85.60% carbon by mass, what is the empirical formula?CH3CHCH2CH4
In order to find an empirical formula of a compound with a given percent composition of the elements that compose this molecule, we need so start by assuming an initial mass of 100 grams (it can be any value, but we usually choose 100 grams because it is easier to work on)
Now, if this compound has 100 grams, we can find the mass of each element and with that information, we can find the number of moles of each one
Write the basic equilibrium equation for NH₃
The question requires us to write the chemical reaction equation that represents the basic equilibrium for ammonia (NH3).
A general basic equilibrium equation can be written as:
[tex]B_{(aq)}+H_2O_{(l)}\to HB^{+_{}}_{(aq)}+OH^-_{(aq)}[/tex]where the substance B "accpets" a H+ ion and the reaction produces OH- ions as product.
Considering the information above, we can write the following basic equation for NH3:
[tex]NH_3_{(aq)}+H_2O_{(l)}\to NH_4^{+_{}}_{(aq)}+OH^-_{(aq)}[/tex]where ammonia receives an H+ ion, forming NH4+ ion and OH- ions.
****100 POINTS**** *WILL MARK BRAINLIEST* !!PLEASE HELP ASAP!! A manufacturer of building materials is designing a new product to be used as structural support for houses being built in the southwestern U.S. desert. Describe two macroscopic properties that should be considered by the manufacturer when designing the product.
Perhaps you like the appearance of rocks and boulders but prefer a material that stays cool in the desert heat. In this case, concrete or travertine should be your top picks. These materials have a high thermal mass and absorb the coolness of the earth below rather than the hot sun overhead
Sometimes you like how rocks and boulders look, but you'd rather have something that keeps cool in the hot desert. In this circumstance, limestone or concrete ought to be your top choices.
What is desert ?Deserts are incredibly arid places where well-adapted flora and animals can be found. Deserts may be divided into four basic categories are hot and dry, semi-arid, coastal, and cold.
The majority of specialists concur that a desert is any region of land with annual precipitation totals of less than 25 cm (10 inches). In a desert, evaporation frequently much outweighs yearly precipitation. Water is scarce for plants and other living things in all deserts.
Thus, Due to their large thermal mass, these materials absorb the cooling of the earth below rather than the heat from the sun above. Something that keeps cool in the hot desert.
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What is the electron figuration of selenium
The electron configuration of selenium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁴.
Selenium is an element of atomic number 34. Electronic configuration helps us in understanding the distribution of electrons in their atomic and sub-atomic sub-shells easily. For writing an element in electronic configuration, a standard notation is to be followed for placing the electrons accordingly in the sub-shells.
The element Selenium with atomic number 34 has 34 electrons in it. Therefore, the nearest noble gas found to Selenium is Argon. Argon has a complete shell of electrons with its configuration as 1s² 2s² 2p⁶ 3s² 3p⁶. With reference to the electronic configuration of Argon, the electronic configuration of Selenium could be found easily.
It could be found from the electrons filling according to the energy of shells that Selenium occupies till the 4th shell until the p sub-shell.
Therefore, the electronic configuration of Selenium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁴.
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How many grams of olive oil will fit into a container that holds 5 L?
ANSWER
The mass of olive oil to 1 significant figure is 4000g
STEP-BY-STEP EXPLANATION
Given information
The volume of the container = 5.0L
The specific gravity of olive oil = 0.703 g/mL
Let x represents the mass of the olive oil
To calculate the mass of olive oil, we will be using the formula below
[tex]\text{Density = }\frac{\text{ mass}}{\text{ volume}}[/tex]Firstly, we need to find the density of olive oil using the below formula
[tex]\begin{gathered} \text{Specific gravity = }\frac{density\text{ of olive oil}}{\text{density of water}} \\ \text{Density of water = 0.999 g/ml} \\ 0.703\text{ = }\frac{\text{ density of olive oil}}{\text{ 0}.999} \\ \text{cross multiply} \\ \text{Density of olive oil = 0.703 }\cdot\text{ 0.999} \\ \text{ density of olive oil = 0.702297 g/ml} \end{gathered}[/tex]Therefore, the density of olive oil is 0.702297 g/ml
To have unit consistency, we need to convert the volume from Liters to milliliters
Recall that, 1 Liter is equivalent to 1000mL
Let x represents the volume to be converted to mL
[tex]\begin{gathered} 1\text{ }\rightarrow\text{ 1000} \\ 5\text{ }\rightarrow\text{ x} \\ \text{cross multiply} \\ 1\cdot\text{ x = 1000 }\cdot\text{ 5} \\ x\text{ = 500mL} \end{gathered}[/tex]Since the volume is 5000mL, we can now find our mass
[tex]\begin{gathered} \text{Density = }\frac{mass}{\text{volume}} \\ 0.702297\text{ = }\frac{mass}{5000} \\ \text{cross multiply} \\ \text{mass = 0.702297 x 5000} \\ \text{mass = 3}511.485\text{ gram} \\ The\text{ mass of olive oil to 1 significant figure is 4000 grams} \end{gathered}[/tex]Write the formula for the following compounds.
The cation, anion, and formula for the given compounds are as follows:
sodium iodide: Na⁺; I⁻; Nalzinc sulfide: Zn²⁺; S²⁻; ZnSmagnesium nitride: Mg²⁺; N³⁻; Mg₃N₂barium phosphide: Ba²⁺; P³⁻; Ba₃P₂calcium chloride: Ca²⁺; Cl⁻; CaCl₂aluminum fluoride: Al³⁺; F⁻; AlF₃lithium oxide: Li⁺; O²⁻; Li₂OWhat is the formula of a compound?The formula of a compound is the formula that represents the compounds using the symbols of the elements and showing the ratio in which the elements combine to form the compound.
The ratio in which they combine is written as subscripts in the formula.
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To correctly balance the half reaction, what would you need to add?
1) Balance the chemical equation.
[tex]Se\rightarrow Se^{2-}[/tex]In order to balance the equation, we can add two electrons to the reactants.
So, the balance equation is
[tex]2e^-+Se\rightarrow Se^{2-}[/tex]___ H2SO4 + __KOH → __K2SO4 +__H2 Obalance the equation
Explanation:
We have to balance this equation:
___ H₂SO₄ + __ KOH ----> __ K₂SO₄ + __ H₂O
The first step is to determine the number of atoms of each element that we have on both sides of the equation.
___ H₂SO₄ + __ KOH ----> __ K₂SO₄ + __ H₂O
K: 1 K: 2
S: 1 S: 1
H: 3 H: 2
O: 5 O: 5
We have 1 atom of K on the left side of the equation and there are 2 atoms of K on the rigth side of the equation. To balance the number of K atoms we can change the coefficient for KOH and write a 2 there.
___ H₂SO₄ + 2 KOH ----> __ K₂SO₄ + __ H₂O
K: 2 K: 2
S: 1 S: 1
H: 4 H: 2
O: 6 O: 5
We balanced the K. The S atoms are already balanced. Let's focus on H. We have 4 atoms of H on the left and 2 atoms of H on the right side of the equation. We can change the coefficient for H₂O and write a 2 there to get 4 atoms of H on the right side.
___ H₂SO₄ + 2 KOH ----> __ K₂SO₄ + 2 H₂O
K: 2 K: 2
S: 1 S: 1
H: 4 H: 4
O: 6 O: 6
We balanced the H and we also changed the number of O atoms on the right side and also balanced them. The balanced equation is:
H₂SO₄ + 2 KOH ----> K₂SO₄ + 2 H₂O
Answer: H₂SO₄ + 2 KOH ----> K₂SO₄ + 2 H₂O
Be sure to answer all parts.The equilibrium constant (Kc) for the formation of nitrosyl chloride, an orange-yellow compound, from nitric oxide and molecular chlorine 2NO(g) + Cl2(g) ⇌ 2NOCl(g) is 2 × 105 at a certain temperature. In an experiment, 6.00 × 10−2 mole of NO, 6.70 × 10−3 mole of Cl2, and 4.00 moles of NOCl are mixed in a 1.30−L flask. What is Qc for the experiment? × 10(Enter your answer in scientific notation.) In which direction will the system proceed to reach equilibrium? The reaction will proceed to the left. The reaction will proceed to the right. The reaction is at equilibrium.
STEP-BY-STEP EXPLANATION*
Given information*
[tex]\begin{gathered} \text{The number of moles of NO = 6.00 }\times10^{-2}\text{ moles} \\ \text{The number of moles of Cl2 = 6.7 }\times10^{-3}\text{ moles} \\ \text{The number of moles of NOCl = 4.00 moles} \\ K_c\text{ = 2 }\times10^5 \end{gathered}[/tex]The first step is to write the balanced equation of the chemical reaction*
[tex]2NO_{(g)}+Cl_{(2)(g)}\rightleftarrows2NOCl_{(g)}[/tex]The next step is to write the chemical equilibrium expression for the above reaction*
Hi. Can I get help with question number 49, please?
The definition of definite shape and volume is a definition of the solid state of matter. The molecules of the compound are so tightly bound that they maintain their shape regardless of the container in which they are contained.
Within the options we see a liquid (l), two gases(g), and a solid described with the suffix s, this is the I2(s), therefore this will be the correct option.
Answer: a. I2(s)
H2O(I)+40.7 KJ > H2O(g)endothermic or exothermic
ANSWER
Endothermic reaction
EXPLANATION
Given that;
[tex]\text{ H}_2O_{(l)}\text{ + 40.7KJ }\rightarrow\text{ H}_2O_{(g)}[/tex]In the reaction above, there is a transition from liquid water to steam. This phase change is called boiling.
During the process, heat is absorbed from the surroundings.
Therefore, the reaction is an endothermic reaction.
How do you find the slopeAnd the equation as well
Answer:
Explanation :
Can you please help me fast
Answer:
C
Explanation:
the answe is naturally occurring
(give me brainliest )
I don’t understand how to solve this and I don’t get ionic equation
Explanation:
Spectator ions refers to elements/molecules that do not form part of the reaction. Basically, these elements/molecules are in the same state in the reactant and product side. From the given reaction, Ca and SO4 change their state from aqueous to solid and Na and Cl do not change their state. Therefore, Na and Cl are spectator ions and Ca and SO4 are not spectator ions.
Answer:
The correct option is C.
What's the volume of 0.2 mol of hydrogen at STP.
Answer
4.48 L
Explanation
At STP, the volume of 1 mol of any gas occupies 22.4 L
Therefore, the volume 0.2 mol of hydrogen at STP = (0.2 mol/1 mol) x 22.4 L = 4.48 L
. A Nucleopore membrane is characterised with permporometry using cyclohexane as condensable vapour. At a relative pressure of 0.78 a high oxygen flux can be observed which does not increase further upon decreasing the relative vapour pressure. The t-layer of cyclohexane in the pore is 0.5 nm. The experiment is performed at 34°C. The saturation pressure of cyclohexane at 34°C is 192.5 mbar. a) Calculate the vapour pressure of cyclohexane at a relative pressure of 0.78. b) What can you say about the pore size distribution in this membrane? c) What is/are the pore radius/radii in this membrane
A Nucleopore membrane is characterised with permporometry using cyclohexane as condensable vapour. At a relative pressure of 0.78 a high oxygen flux can be observed which does not increase further upon decreasing the relative vapour pressure. The t-layer of cyclohexane in the pore is 0.5 nm. The experiment is performed at 34°C. The saturation pressure of cyclohexane at 34°C is 192.5 mbar
Vapour pressure is a measure of the tendency of a material to change into the gaseous or vapour state and also increases the temprature
1. The vapour pressure of cyclohexane at a relative pressure of 0.78 is 0.104 atm
2. Pore size distribution in this membrane is 0.5 nm
3. The pore radius/radii in this membrane is 9.0
Here given data is
relative pressure = 0.78
Pore = 0.5 nm.
Temprature = 34°C
saturation pressure = 192.5 mbar
We have to find vapour pressure = ?
Vapor pressure = ln(P₁/P₂) = (ΔHvapor/R) - (1/T₁)
Vapor pressure = ln(1 /192.5 mbar) = ( 0.78 /8.314) - (1/ 34°C)
Vapor pressure = -5.26 = 0.093-0.06
Vapor pressure = 0.104 atm
Where pore radius/radii in this membrane is calculated by formula
(P/P₀) = -2rT
(0.78/ 0.104 ) = -2×34°C
7.5 = -68
= 9.0
Therefore radius pore in this membrane is 9.0
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21. If you have 350 milliliters (mL) of a 500-milligramper liter (mg/L) solution of alum (aluminum sulfate),how much water would you have to add to bring theconcentration down to 100 mg/L? Assume that youare adding water that does not contain any alum (C2=0).1. 70 mL2. 1,400 mL3. 143 mL4. 1,750 mL
1750mL
Explanations:In order to get the required volume, we will use the dilution formula expressed as:
[tex]C_1V_1=C_2V_2[/tex]where:
C₁ and C₂ are the initial and final concentration respectively
V₁ and V₂ are the initial and final volume respectively
Given the following parameters:
C₁ = 500mg/L
C₂ = 100mg/L
V₁= 350mL
Required
V₂
Substitute the given parameters into the formula to have:
[tex]\begin{gathered} V__2=\frac{C_1V_1}{C_2} \\ V_2=\frac{500\times350}{100} \\ V_2=\frac{175,000}{100} \\ V_2=1750mL \end{gathered}[/tex]Hence the amount of water needed is 1750mL
Whatisthenumberof moles of glucose(C₆H₁₂O₆)in 0.500L of a 0.40 Msolution?
Answer:
[tex]0.2\text{ mole}[/tex]Explanation:
Here, we want to get the number of moles of glucose in 0.5L of 0.4 M solution
Firstly, we need to recall that concentration or molarity is of the unit mol/dm^3
Mathematically, 1L is 1 dm^3 , thus, we have it that 0.4M is the same as 0.4 mol/dm^3
Now, to get the number of moles from molarity, we have to multiply the molarity by the volume
We have that as:
[tex]\begin{gathered} \text{Number of moles = molarity }\times\text{ volume} \\ \text{Number of moles = 0.4 }\times0.5\text{ = 0.2 mole} \end{gathered}[/tex]Rigor mortis occurs because ________.
A) the cells are dead
B) sodium ions leak out of the muscle
C) no ATP is available to release attached actin and myosin molecules
D) proteins are beginning to break down, thus preventing a flow of calcium ions
Answer:
C) no ATP is available to release attached actin and myosin molecules
Explanation:
Rigor mortis occurs because no ATP is available to release attached actin and myosin molecules. Therefore, the correct option is option C.
What is Rigor mortis?The fourth stage of death is known as rigour mortis, or postmortem rigidity. One of the telltale indications of death is the stiffening of the corpse's limbs as a result of postmortem chemical changes inside the muscles. Rigor mortis can develop in humans as quickly as eight hours after death. Rigor mortis does not constitute a lifelong condition, despite popular belief and mythology, and it starts to subside within hours of commencement.
It typically only lasts 8 hours at "room temperature." Following death, an organism's aerobic respiration stops, reducing the supply of oxygen needed to produce adenosine triphosphate (ATP). When a muscle relaxes, ATP is necessary to cause the actin-myosin cross-bridges to separate. Rigor mortis occurs because no ATP is available to release attached actin and myosin molecules.
Therefore, the correct option is option C.
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Convert 57.0 degrees C todegrees F.[?] °FT in degrees F
In order to convert a temperature in celsius to a temperature in Fahrenheit, we need to use the following conversion formula:
(°C*9/5) + 32
Now we use the 57°C value in the formula:
(57 * 9/5) + 32
(513/5) + 32
102.6 + 32
134.6
The temperature of 57° in Fahrenheit will be 134.6°
The first ionization energy of magnesium is 738 kJ/mol. A good estimate for the second ionization energy of magnesium is:
The second ionization energy is always greater than the first one. So, the answer is between 1450and 6900 kJ/mol.
Each ionization energy means the energy that it takes to separate the outer electron from the atom. In this case, the best estimation of the second ionization energy is 6900 kJ/mol because it would take more than double the first ionization energy.
Therefore, the answer is d.
1. What is the molarity of a solution of HNO3 that contains 25.2 g of HNO3 in 1.0 L of solution?
Explanation:
First, let's discover the quantity in moles of 25.2 g of HNO3. For this, we use the following formula: n = m/MM
MM of HNO3 = 63 g/mol
m = 25.2
n = 25.2/63
n = 0.4 moles
Now using the following formula: M = n/V
We can find the molarity of the solution:
n = 0.4 moles
V = 1L
M = 0.4/1
M = 0.4 mol/L
Answer: 0.4 mol/L
0/1 pt 1021 0If 5.47 mol of krypton gas occupies 186.5 L, what volume would 14.1 mol of krypton occupy at the sametemperature and pressure?Use the correct number of significant figures in your answer.Question 5Submit Question Jump to Answer
Answer:
The new volume is 480.75L.
Explanation:
The given information from the exercise is:
- Initial amount of moles (n1): 5.47 moles
- Initial volume (V1): 186.5L
- Final amount of moles (n2): 14.1 moles
1st) We have to replace the values of V1 and n1 in the Idea Gases formula:
[tex]\begin{gathered} P*V_1=n_1*R*T \\ P*186.5L=5.47moles*0.082\frac{atm*L}{mol*K}*T \\ \frac{186.5L}{5.47moles*0.082\frac{atm*L}{mol*K}}=\frac{T}{P} \\ 415.8\frac{K}{atm}=\frac{T}{P} \end{gathered}[/tex]Now we have a value for the relation T/P that remains constant.
2nd) Finally, we have to replace the value of the relation T/P and the amoun of moles n2:
[tex]\begin{gathered} P*V=n_2*R*T \\ P*V=14.1moles*0.082\frac{atm*L}{mol*K}*T \\ V=14.1moles*0.082\frac{atm*L}{mol*K}*\frac{T}{P} \\ V=14.1moles*0.082\frac{atmL}{molK}*415.8\frac{K}{atm} \\ V=480.75L \end{gathered}[/tex]So, the new volume is 480.75L (rounded to 481L).
Place these in order from smallest to largest.
Ca, Fe, Ni, or Br
Order from smallest to largest are :
Br < Ni < Fe < Ca
The atomic radius is the distance between centre of nucleus of atom to the outermost shell. The trend of atomic radius in the periodic table is it increases from top to bottom as no. of shells increases. Atomic radius from left to right in the periodic table is decreases because the number of electrons increases but number of shells remain same . The valence electron are in the same outermost shell. This leads to the increase in attractive forces and this reduces the atomic radius.
Thus, Order from smallest to largest are :
Br < Ni < Fe < Ca
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The first and second ionization energies of K are 419 kJ/mol and 3052 kJ/mol, and those of Ca are
590 kJ/mol and 1145 kJ/mol, respectively. Compare their values and comment on the differences.
Explanation:
Already it can be noted that both the first and second ionization energy of Ca is greater than that of K. In order to fully understand why this is, we must first look at both elements and their electron configuration.
Ionization energy is basically the energy required to remove the outermost electron in an atom
There are 3 factors that affect the ionization energy:
the size of positive nuclear chargedistance of the outermost electron from the nucleusscreening/shielding effect from inner shellsFrom the attachment of the atomic radii trend in the periodic table, we know that atomic radius decreases moving across a period i.e meaning that the outermost shell is closer to the nucleus. And we know that atomic radius increases down a group.
And in the case of K and Ca, we note that Ca has a smaller atomic radii than K, this is because an extra proton and electron is added to the atom that differs it from the previous member, K. Moving from K to Ca, we see that the electron was added to the same shell and there is another proton in the nucleus therefore the attraction of the outermost shell to the nucleus as with the size of the positive nuclear charge increased whilst the shielding effect remained the same for K and Ca, this makes it more difficult now to remove the outer most electron of Ca hence the increased ionization energy as compared to K.