1) Aufbau principle is a scheme used to reproduce the electron configurations of the ground states of atoms by successively filling subshells with electrons in a specific order, filling subshells in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f.
First exceptions to the Aufbau principle is for example chromium atom (Cr).
Chromium has atomic number 24, it means it has 24 protons and 24 electrons.
The Aufbau principle predicts the configuration [Ar] 3d⁴ 4s².
But the correct electron configuration of chromim atom is:
₂₄Cr 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹ or [Ar] 3d⁵ 4s¹.
In chromium, half full d-sub level (3d) is more stable than a partially filled d sub-level (3d⁴), that is why an electron from the 4s orbital goes to a 3d orbital.
2) Second example is gallium atom (Ga).
Gallium has atomic number 31, it has 31 protons and 31 electrons.
The Aufbau principle predicts the configuration:
₃₁Ga 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p¹.
The correct electron configuration for gallium atom is:
₃₁Ga 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p¹.
That is because 3d subshell has lower energy, when is filled with electrons, than 4s subshell.
Valence electrons are in 4s and 4p orbitals, because when gallium loses three electrons, it has electron configuration:
₃₁Ga³⁺ 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰.
What is true of a decomposition reaction? The reactants are usually a metal and a nonmetal. The reactants are generally two ionic compounds in an aqueous solution. The addition of energy in the form of heat or electricity is often required. Water is usually one of the reactants.
Answer
In a true decomposition reaction, the addition of energy in the form of heat or electricity is often required.
Explanation
A decomposition reaction is a chemical reaction that starts with single reactants to give new compounds as the products. These reaction requires a source of energy that could be light, heat or electricity to facilitate the breaking-down of the chemical bonds.
Answer:
The addition of energy in the form of heat or electricity is often required.
how many individual atoms make up one unit of aluminum chloride, ALCL3?
4 atoms make up aluminium chloride: 1 aluminum atom and 3 chlorine atoms
A substance which produces hydroxide ions when placed in water is a(n) _____.
A:dehydrate
B:base
C:solvent
99 points to whoever best answer.
The answer you're looking for is B:base
The base is disestablished in the water, and the molecules form into ions and produces OH- ions.
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Hope this helped:D
Question: A substance which produces hydroxide ions when placed in water is a _____.
Answer: base
Explanation: a substance that contains hydrogen causes to produce hydrogen ions
question answered by
(jacemorris04)
When molecules slow down, they expand.
A
True
B
False
False. <--- This is wrong I was thinking of atoms
Molecules do expand when they slowdown...
Hello.
The answer: A. True.
When mouecules slow down they can expend and this is how gas is made.
Have a nice day.
What salt is formed by the reaction of potassium hydroxide and hydrochloric acid?
Potassium hydroxide (KOH) is formed when Potassium forms ionic bonds with OH-ions while Potassium Oxide (K2O) is formed when potassium forms ionic bonds with the Oxide (O2-) ions. i.e. This reaction is a neutralization reaction and occurs when an acid (HCl) reacts with a base (KOH).
Answer: potassium chloride
Explanation:
Double displacement reaction is one which involves exchange of ions. Neutralization is a type of double displacement reaction in which an acid combines with a base to form salt and water, the reaction is called as neutralization reaction.
[tex]KOH+HCl\rightarrow KCl+H_2O[/tex]
Thus the salt formed is potassium chloride which has the chemical formula [tex]KCl[/tex].
Hey can you please help me with this I really need y’all
Which of the following is correctly abbreviated SI unit describing the mass of an object?
A) kg
B) mol
C) m
D) M
Which of the following is correctly abbreviated SI unit describing the mass of an object?
A) kg
A) kg is your answer
"Mass" is weight without gravity, and so the SI unit would also use the weight measurement. (You solve by dividing the force of gravity from the total weight to get mass.)
~
is P2I4 or Diphosphorus tetraiodide covalent or ionic?
Diphosphorus tetraiodide is a covalent compound.
It has low melting point as compared to ionic compounds
It is a rare compound where the oxidation state of Phosphorous is +2.
It is also termed as subhalide of phosphorous.
Answer: covalent bond.
Explanation:
A covalent bond is formed when an element shares its valence electron with another element. This bond is formed between two non metals.
An ionic bond is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element and the element which accepts the electrons is known as electronegative element. This bond is formed between a metal and an non-metal.
As [tex]P_2I_4[/tex] or Diphosphorus tetraiodide is made up of phosphorous and iodine which are both non metals , it is a covalent bond.
List the 3 ways carbon can enter the ocean?
Final answer:
Three ways carbon can enter the ocean are through running water, atmospheric dissolution, and decomposition of aquatic organisms.
Explanation:
Carbon can enter the ocean through three main ways:
Running water: Carbon is slowly dissolved in rocks by running water and eventually ends up in the ocean.Atmospheric dissolution: The top layer of ocean water dissolves some carbon dioxide out of the atmosphere.Decomposition of aquatic organisms: Carbon enters ocean water from the decomposition of aquatic organisms.How do properties, such as Density, help us to classify and identify matter?
Density can be defined in terms of the mass of a substance present in a certain volume.
i.e. Density = Mass/ volume
It helps classify and identify matter due to the following reasons:
1) Density is an intensive property. For a given substance the density will remain the same irrespective of the amount in which it is present.
For example: The density of Aluminum (Al) = 2.7 g/cm3. This value is a constant at a certain temperature and pressure. Therefore, the density will remain the same for 1 kilogram or 1 mg of Al
2) Different elements/compounds have different values of densities which is characteristic of that substance
A gas occupies volume of 30 milileters at 273 K if the temperature is increased to 364 k while the pressure remains constant what will be the volume of the gas
Answer:
40 mL
Step-by-step explanation:
The pressure is constant.
The only variables are volume and temperature, so we can use Charles’ Law.
V₁/T₁ = V₂/T₂ Multiply each side by T₂
V₂ = V₁ × T₂/T₁
V₁ = 30 mL; T₁ = 273 K
V₂ = ?; T₂ = 364 K
V₂ = 30 × 364/273
V₂ = 40 mL
Question: Draw a valid Lewis structure for the molecule CH3NO in which there are no nonzero formal charges on any of the atoms. This structure should not include any bonds between N and O.
what do you do with the oxygen?
The mentioned molecule with formula, CH₃NO where no bond is found between N and O can be depicted as formamide is shown in the attachment below.
The formal charges = Number of valence electrons for the atom (V) - the number of electrons in lone pairs (N) - 1/2 (number of electrons in bond pairs, B)
FC = V - N - B/2
Thus, there is a need to calculate valence electrons, electrons in lone pairs, and the number of electrons in bond pairs for each atom in the mentioned molecule.
V or valence electrons on C = 4e, on H = 1e, on N = 5e, and on O = 6e.
N or electrons in lone pairs on C = 0e, on H = 0e, on N = 2e, and on O = 4e.
B or number of electrons in bond pairs for C = 8e, for H = 2e, for N = 6e, and for O = 4e.
Thus, the formal charges for each will be,
C = 4 - 0 - (8/2) = 0
H = 1 - 0 - (2/2) = 0
N = 5 - 2 - (6/2) = 0
O = 6 - 4 - (4/2) = 0
Lewis dot structure for the given molecule is given in the attachment below:
Answer : The Lewis-dot structure of [tex]CH_3NO[/tex] is shown below.
Explanation :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is, [tex]CH_3NO[/tex]
As we know that carbon has '4' valence electrons, hydrogen has '1' valence electron, nitrogen has '5' valence electrons and oxygen has '6' valence electrons.
Therefore, the total number of valence electrons in [tex]CH_3NO[/tex] = 4 + 3(1) + 5 + 6 = 18
According to Lewis-dot structure, there are 12 number of bonding electrons and 6 number of non-bonding electrons.
Now we have to determine the formal charge for each atom.
Formula for formal charge :
[tex]\text{Formal charge}=\text{Valence electrons}-\text{Non-bonding electrons}-\frac{\text{Bonding electrons}}{2}[/tex]
[tex]\text{Formal charge on O}=6-4-\frac{4}{2}=0[/tex]
[tex]\text{Formal charge on C}=4-0-\frac{8}{2}=0[/tex]
[tex]\text{Formal charge on N}=5-2-\frac{6}{2}=0[/tex]
[tex]\text{Formal charge on }H_1=1-0-\frac{2}{2}=0[/tex]
[tex]\text{Formal charge on }H_2=1-0-\frac{2}{2}=0[/tex]
[tex]\text{Formal charge on }H_3=1-0-\frac{2}{2}=0[/tex]
Hence, the Lewis-dot structure of [tex]CH_3NO[/tex] is shown below.
Is a microvilli is a tiny finger like projection that kills bacteria in the lymphatic system? true or false
Villi are tiny finger like projections present in the inner epithelial lining of the intestine. Each finger like villi is further divided into microvilli, which is the extension of plasma membrane of each epithelial cell of the villi. These villi and microvilli present on the inner surface of the intestine provide a greater surface area and this enhances the digestion and absorption of the nutrients.
Therefore, the correct answer is false as a microvilli is the tiny finger like projection of the inner epithelial cells of the small intestine that has absorptive functions.
iron plus lead (||)sulfate react forming iron (||) sulfate plus lead
Final answer:
Fe(s) + PbSO4(s) = FeSO4(aq) + Pb(s)
Explanation:
The question involves a reaction where iron reacts with lead (II) sulfate, resulting in the formation of iron (II) sulfate and lead. This type of reaction is a single displacement reaction where a more reactive metal (iron) displaces a less reactive metal (lead) from its compound. To balance the reaction, we would write it as:
Fe(s) + PbSO4(s) = FeSO4(aq) + Pb(s)
Here, solid iron reacts with solid lead (II) sulfate to produce aqueous iron (II) sulfate and solid lead. This reaction is guided by the activity series, which predicts whether certain chemical reactions will occur based on the reactivity of the metals involved. In this case, since iron is more reactive than lead, it can displace lead from its sulfate compound.
between sour soup,melting of candle wax,rusting, and burning which is not a chemical reaction
Sour soup is not a chemical reaction
What are some common properties of covalent compounds
Most covalent compounds have relatively low melting points and boiling points.
Covalent compounds usually have lower enthalpies of fusion and vaporization than ionic compounds.
Covalent compounds tend to be more flammable than ionic compounds.
Covalent compounds are characterized by their lower melting and boiling points, poor conductivity, varied solubility in water depending on molecular polarity, and being typically gases or liquids at room temperature. These properties stem from the sharing of electrons between nonmetallic elements, forming covalent bonds.
Covalent compounds exhibit unique characteristics due to the sharing of electrons between nonmetallic elements. These shared electrons create bonds that are central to the distinct properties of covalent compounds. A deeper understanding of these properties highlights the differences between covalent and ionic compounds.
Key Properties of Covalent Compounds
Lower Melting and Boiling Points: Covalent compounds generally have much lower melting and boiling points compared to ionic compounds. This is because the intermolecular forces in covalent compounds are weaker than the ionic bonds in ionic compounds.Poor Conductivity: In any state, whether solid, liquid, or gas, covalent compounds are poor conductors of electricity because they are electrically neutral.Solubility: Most covalent compounds are insoluble in water, and their solubility largely depends on molecular polarity.Physical State: Many covalent compounds are liquids or gases at room temperature, indicating their weaker forces and lower energy stability compared to ionic compounds, which are often solid.In essence, covalent bonding results in compounds with distinct physical states and functionalities, emphasizing the diversity of chemical compounds and their varied applications.
Which of the following is not a correct chemical equation for a double displacement reaction? (2 points) 2RbNO3 + BeF2yields Be(NO3)2 + 2RbF CaCl + LiCO3yields CaCO3 + LiCl Na3PO4 + 3KOH yields 3NaOH + K3PO4 2MgI2 + Mn(SO3)2yields 2MgSO3 + MnI4
Answer: [tex]2MgI_2+Mn(SO_3)_2\rightarrow 2MgSO_3+MnI_4[/tex]
Explanation:
Double displacement reaction: it is a chemical reaction in which the reactants exchanges their ions to form new compounds as a products.
[tex]AB+CD\rightarrow AD+CB[/tex]
All the reaction are example of double displacement reaction beside reaction where magnesium iodide is reacting with manganese(II) sulfate to give magnesium sulfate and manganese(IV) iodide .
[tex]2MgI_2+Mn(SO_3)_2\rightarrow 2MgSO_3+MnI_4[/tex]
In this reaction , charge on manganese have changed from 2+ to 4+. Manganese in getting oxidized. Example of an oxidation reaction. Hence, this reaction is not an example of double displacement reaction.
explain why subscripts cannot change when balancing a chemical equation
not be changed to balance an equationSubscripts are part of the chemical formula for reactants or products and can
Changing a subscript changes the substance represented by the formula
Subscripts are the identity of the element (the number of atoms) whereas coefficients are the number of molecules of the element.
If you change the subscript, you change the number of atoms an element has. This changes the entire element since each element in the periodic table have different atomic numbers.
what types of charge does a
What are the atomic number and mass number of this atom
which two units commonly measure heat? pick two answers
a. watts
b. joules
c. calories
d. amperes
Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6Li (s) + N2 (g) → 2Li3N (s) In a particular experiment, 4.00-g samples of each reagent are reacted. The theoretical yield of lithium nitride is ________ g.
6.69 g.
ExplanationMake sure the chemical equation is balanced:
[tex]6\; \text{Li}\; (s) + \text{N}_2 \; (g) \to 2\; \text{Li}_3\text{N}\; (s)[/tex]
Assuming that one mole of N₂ is consumed. How many grams of each reactant will that take? Refer to a periodic table for data on atomic mass.
6 × 6.94 = 41.64 grams of Li;1 × (2 × 14.01) = 28.02 grams of N₂.4.00 grams of each reactant are available. How many moles of N₂ can they consume?
4.00 grams of Li will lead to up to 4.00 / 41.64 = 0.09606 moles of the reaction.4.00 grams of N₂ will lead to up to 4.00 / 28.02 = 0.1428 moles of the reaction.However, only 0.09606 moles of the reaction is possible, since Li would have ran out before all 4.00 grams of N₂ are used up.
Each mole of the reaction makes 2 moles of Li₃N. 0.09606 moles of the reaction will produce 0.09606 × 2 × (3 × 6.94 + 14.01) = 6.69 grams of Li₃N.
For a 0.50 molal solution of sucrose in water, calculate the freezing point and the boiling point of the solution.
Answer:
-0.93 °C; 100.26 °C
Step-by-step explanation:
(a) Freezing point depression
The formula for the freezing point depression ΔT_f is
ΔT_f = iKf·b
i is the van’t Hoff factor: the number of moles of particles you get from a solute.
For sucrose,
Sucrose (s) ⟶ sucrose (aq)
1 mole sucrose ⟶ 1 mol particles i = 1
ΔT_f = 1 × 1.86 × 0.50
ΔT_f = 0.93 °C
T_f = T_f° - ΔT_f
T_f = 0.00 – 0.93
T_f = -0.93 °C
(b) Boiling point elevation
The formula for the boiling point elevation ΔTb is
ΔTb = iKb·b
ΔTb = 1 × 0.512 × 0.50
ΔTb = 0.256 °C
Tb = Tb° + ΔTb
Tb = 100.00 + 0.256
Tb = 100.26 °C
Answer:
Explanation:
1. If the Kf = 1.86 ºC / m for water, what is the freezing point depression for the sucrose solution?
ΔT = iKf m
i=1 for sucrose
Kf = 1.86 ºC / m
m = 0.50
ΔTf = 1.86 x 0.50 = 0.93 ºC
2. If the Kb = 0.512 ºC / m for water, what is the boiling point elevation for the sucrose solution?
ΔT = i Kb m
i=1 for sucrose
Kf = 0.512 ºC / m
m = 0.50
ΔTf = 0.512 x 0.50 = 0.26 ºC
If an automobile travels at 30. m/s for 2 minutes, how far has the car traveled?
3600 miles! to get this answer you first need to know that
60+60= 120
then just times tht by 30 and you get 3600!
Final answer:
The car traveling at a constant speed of 30.0 m/s for 2 minutes covers a distance of 3600 meters.
Explanation:
To calculate the distance traveled by a car that moves at a constant speed, we can use the formula distance = speed × time. Given that the car travels at a constant speed of 30.0 m/s for 2 minutes, we first need to convert the time from minutes to seconds since the speed is given in meters per second.
There are 60 seconds in a minute, so 2 minutes equals 2 × 60 = 120 seconds.
Now, we can calculate the distance:
Distance = Speed × Time
Distance = 30.0 m/s × 120 s
Distance = 3600 meters
Therefore, the car has traveled a distance of 3600 meters.
Can someone PLEASE HELP me?
How can you tell if a bond is Covalent?
AgI + Na2S Ag2S +NaI=
The equation needs to be balanced and written as,
[tex]2AgI+1 Na_{2} S[/tex]→[tex]1Ag_{2} S+2NaI[/tex]
Both side of compound should contain equal masses.
A metal has higher reactivity than mag esoum where would the metal be on a periodic table
Answer is: below magnesium in group 2 or in group 1 (left from magnesium).
Reactivity series is an empirical progression of a series of metals, arranged by their reactivity from highest to lowest (alkaline metals have highest reactivity and Noble metals lowest reactivity).
This series are used to summarize information about the reactions of metals with acids or water, double displacement reactions (more reactive metals displace metals with lower reactivity) and the extraction of metals from their ores.
Sodium and potassium (group 1 - alkaline metal) are more reactive than magnesium.
Strontium and barium (group 2 in periodic table) are higher in this group from magnesium. Strontium is stronger reducing agent than magnesium, gives electrons easier.
which of these substance are likely to have a bitter taste antacod vi ger or anyacod toothpaste or orange jucoe and vinger or orange juice toothpaste
Answer : The correct option is, Antacid and toothpaste.
Explanation :
The property of an acid is that they are sour in taste and the property of base is that they are bitter in taste.
In the given question, vinegar, orange juice are the acids and antacids, toothpaste are the bases.
Therefore, the option Antacid and toothpaste are likely to have a bitter taste.
Write a balanced equation for double replacement of KOH+ZnCl2
Answer :
Double replacement reaction : It is a type of reaction in which a positive cation and a negative anion of the reactants react to give a new compound as a product.
[tex]AB+CD\rightarrow AD+CB[/tex]
In this, A and C are the cations and B and D are the anions.
When one mole of potassium hydroxide react with the one mole of zinc chloride to give one mole of zinc hydroxide and 2 moles of potassium chloride.
The balanced chemical reaction is,
[tex]KOH+ZnCl_2\rightarrow Zn(OH)_2+2KCl[/tex]
What is the volume(in liters at stp) of 2.50 mil of carbon monoxide
The volume of one mole of substance is 22.4 L
To find the volume of 2.50 moles of carbon monoxide at STP, you multiply the moles by the molar volume at STP (22.4 L/mol), which gives you 56.0 liters.
To calculate the volume of carbon monoxide (CO) at standard temperature and pressure (STP), we should use Avogadro's Law. At STP, one mole of any gas occupies 22.4 liters. Given the amount of carbon monoxide in moles, we can determine the volume it would occupy at STP.
To find the volume:
Volume at STP (V) = Number of moles (n) x Molar volume at STP (Vm)
We know that:
[tex]n = 2.50\ moles\\ V_m = 22.4\ L/mol\ (volume\ occupied\ by\ one\ mole\ of\ gas\ at\ STP)[/tex]
So:
[tex]V = 2.50\ moles \times 22.4\ L/mol\\ V = 56.0\ liters[/tex]
This is the volume of 2.50 moles of carbon monoxide gas at standard temperature and pressure.