The question is incomplete, the complete question is shown in the image attached to this answer
Answer:
1) K
2) F
3) Si
4) Br
Explanation:
If an element has a more negative value of electron affinity, then it has a greater ability to attract an electron.
In each of the following pairs of elements, one element has a more negative electron affinity for certain reasons.
Between K and Ca, the incoming electron in K goes into a 4s orbital which is lower in energy and more stable. For Ca, the electron goes into a 3d orbital which is more unstable.
Between Ne and F, Ne already has a filled outermost shell hence the incoming electron goes into the higher energy 3s level. In F, the electron goes into the 2p level and completes it. Hence F has a more negative electron affinity.
Let us recall that half filled and completely filled orbitals are exceptionally stable. Hence, the electron affinity of Si is more negative than that of P because in P, the electron goes into an exceptionally stable half filled orbital.
Recall that the more the value of Zeff, the more negative the electron affinity hence electron affinity increases across a period; hence, Br has a more negative value of electron affinity than Se.
A student dropped a piece of silver metal into a solution of HCl(aq). He observed the formation of gas bubbles and collected the gas into another test tube. The student performed a splint test and observed that the splint produced a popping sound when he placed the splint into the test tube of the gas. What can be said about the results of this students experiment?
a. The student performed the splint test incorrectly. He should of observed the splint flare up when the splint was placed in the test tube.
b. The student completed the experiment correctly and there were no errors in the experiment.
c. The experiment was performed incorrectly. Silver doesn't react with HCl. Therefore, the student picked up the wrong metal when conducting the experiment.
d. The student performed the splint test incorrectly. He should of observed the flame being extinguished when the splint was placed in the test tube.
Answer:
The student completed the experiment correctly and there were no errors in the experiment.
Explanation:
When a pea size amount of Ag is dropped into a solution of HCl, the following reaction occurs;
Ag(s) + 2HCl(aq) ----> AgCl(aq) + H2(g)
The gas H2 burns with a pop sound. The gas obtained does not react to litmus. The products of the reaction are expected.
Hence, the experiment was properly conducted and the student completed the experiment correctly and there were no errors in the experiment.
The metal tantalum becomes superconducting at temperatures below 4.483 K. Calculate the temperature at which tantalum becomes superconducting in degrees Celsius.
Answer:
The correct answer is "-268.667°C".
Explanation:
Given:
Temperature,
= 4.483 K (below)
Now,
The formula of temperature conversion will be:
⇒ [tex]T(^{\circ} C)=T(K)-273.15[/tex]
By putting the values, we get
⇒ [tex]=4.483-273.15[/tex]
⇒ [tex]=-268.667^{\circ} C[/tex]
Thus the above is the correct answer.
Identify a process that is NOT reversible. Identify a process that is NOT reversible. melting of snow baking of bread deposition of carbon dioxide freezing water melting of aluminum
Answer:
Identify a process that is NOT reversible.
Melting of snow
baking of bread
deposition of carbon dioxide
freezing water
melting of aluminum
Explanation:
A physical change is the one in which there is a change only in its physical state, color, the appearance of the substance. But the chemical composition of the substance remains unchanged.
It is a temporary change and can be reversed easily.
For example:
melting, freezing, deposition etc.
Baking is a permanent change and the chemical composition of the substance changes.
Hence, among the given options, baking of bread is not a reversible change.
Out of the following all are physical changes except baking of bread and physical changes are reversible so the process which is not reversible is baking of bread.
What are physical changes?Physical changes are defined as changes which affect only the form of a substance but not it's chemical composition. They are used to separate mixtures in to chemical components but cannot be used to separate compounds to simpler compounds.
Physical changes are always reversible using physical means and involve a change in the physical properties.Examples of physical changes include melting,boiling , change in texture, size,color,volume and density.Magnetism, crystallization, formation of alloys are all reversible and hence physical changes.
They involve only rearrangement of atoms and are often characterized to be changes which are reversible.
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What is the molecular formula of the structure below?
Picture is attached pls help I’ll mark as brainliest for the right answer
Answer:
C₆H₆
Explanation:
Each border of the figure represents 1 atom of carbon. We have 6 borders = 6 atoms of carbon.
Each atom of carbon form 4 bonds. All the carbons are doing a double bond and a single bond with other carbons. That means are bonded 3 times. The other bond (That is not represented in the figure. See the image) comes from hydrogens. As we have 6 carbons that are bonded each 1 with one hydrogen. There are six hydrogens and the molecular formula is:
C₆H₆This structure is: Benzene
if salt and sand is mixed with distilled water, what will be the residue? and, what will be the filtrate?
Answer:
Filtration is a technique used as a remedy to separate mixes
Explanation:
If you have a sodium, then you will explore that salt dissolves but the sand is still the same.
If the salt in the resin water solution scanners, the sand remains the residue and passes through the filter paper.
All you have to do now is pleasant the salty water so that the water can evaporate, leaving the salt behind.
Voltages listed in textbooks and handbooks are given as standard cell potentials (voltages). What is meant by a standard cell?
Answer:
Find the definition below.
Explanation:
A standard cell is a group of transistors that have a regular electromotive force flowing through them. They follow either the boolean function or the storage function. A technology library that is made up of a collection of standard cells can be used to facilitate the placement, routing, and synthesis of the Application-specific Integrated Circuit (ASIC).
Electronic Design Automation is an example of an apparatus that implements this functionality.
Suppose 20.8 g of sodium iodide is dissolved in 250. mL of a 0.70 M aqueous solution of silver nitrate. Calculate the final molarity of ALL IONS in the solution. You can assume the volume of the solution doesn't change when the sodium iodide is dissolved in it. Round your answer to 3 significant digits.
Answer:
[Ag+] = [NO3-] = 0.700M
0.555M = [Na+] = [I-]
Explanation:
To solve this question we need to find the moles of sodium iodide, NaI, using its molar mass -. With the moles and the volume we can find the molarity of Na+ and I-. The molarity of the ions of silver nitrate, AgNO3 doesn't change because we are assuming the volume doesn't change:
Molarity Ag⁺ = Molarity NO₃⁻ = 0.700M
Moles NaI -Molar mass: 149.89g/mol-
20.8g NaI * (1mol/149.89g) = 0.0139 moles NaI
Molarity:
0.0139 moles NaI / 0.250L = 0.555M = [Na+] = [I-]
Which one of the following is an example of a balanced chemical reaction?
a. 8HCl + 2KMnO4 → 3Cl2 + 2MnO2 + 4H2O + 2KCl.
b. 6HCl + 2KMnO4 → 2Cl2 + 2MnO2 + 4H2O + 2KCl.
c. 2HCl + 2KMnO4 → Cl2 + MnO2 + 2H2O + 2KCl.
d. HCl + KMnO4 → Cl2 + MnO2 + H2O + KCl.
e. HCl + KMnO4 → Cl2 + MnO2 + 2H2O + KCl.
Answer:
Option a.
Explanation:
To determine which is a balanced chemical reaction, see the stoichiometry.
Stoichiometry coefficients are the numbers that appear before the compounds. These numbers indicate moles of substance.
Notice that the number of elements must be the same in both sides of the equation.
In this case, option a is the balanced chemical reaction.
8HCl + 2KMnO₄ → 3Cl₂ + 2MnO₂ + 4H₂O + 2KCl
8 moles of HCl react to 2 moles of potassium permanganate in order to produce 2 moles of magnessium dioxide, 3 moles of chlorine, 2 moles of potassium chloride and 4 moles of water.
8 H, 8 Cl, 2 K, 2 Mn and 8 O
A compound, C7H13Cl, is reacted with sodium ethoxide and gives a single elimination product, C7H12. Treatment with ozone followed by zinc and water gives the compound below. Identify the original compound.
A. 2-chloro-1,1-dimethylcyclopentane.
B. 1-chloro-1,2-dimethylcyclopentane.
C. 4-chloro-1,2-dimethylcyclopentane.
D. 2-chloro-1,3-dimethylcyclopentane.
Answer:2-chloro-1,3-dimethylcyclopentane
Explanation
I have an unknown volume of gas at a pressure of 0.50 atm and a temperature of 325 K. If I raise the pressure to 1.2 atm, decrease the temperature to 320 K, and measure the final volume to be 48 liters, what was the initial volume of the gas?
SHOW YOUR WORK
Answer:
the answer is 2.1 atm
Explanation:
the way people normally do it is by simply deciding the 325k with the 1.2
The chemical formula for hydrogen chloride is HCl A chemist determined by measurements that moles of hydrogen chloride participate in a chemical reaction. Calculate the mass of hydrogen chloride that participates. Be sure your answer has the correct number of significant digits.
The question is incomplete, the complete question is;
. A chemist determined by measurements that 0.015 moles of hydrogen chloride participate in a chemical reaction. Calculate the mass of hydrogen chloride that participates Round your answer to 2 significant digits. x S. ?
Answer:
0.54 g
Explanation:
Recall that;
Number of moles = mass/molar mass
Molar mass of HCl =36.5 g/mol
Mass= number of moles × molar mass
Mass= 0.015 moles × 36 g/mol
Mass= 0.54 g
How many carbon atoms are there in 15 lbs of sugar, C12H22O11?
Answer:
A molecule of sucrose (C12H22O11) has 12 carbon atoms, 22 hydrogen atoms and 11 oxygen atoms.
Explanation:
if this does not help let me know :)
There are 1.4376 × 10²⁶ carbon atoms in 15 lbs of sugar (C12H22O11).
From the given information,
Using the standard conversion method;
1 lbs = 453.592 gram
∴
15 lbs = (453.592 gram × 15 lbs/1 lbs)
= 6803.88 grams
Now, we will need to determine the molar mass of the sugar compound C12H22O11.
Molar mass of C12H22O11 = (12 × 12) +(1 × 22) + (16 × 11)
Molar mass of C12H22O11 = 144 + 22 + 176
Molar mass of C12H22O11 = 342 g/mol
Using the relation:
[tex]\mathbf{Number \ of \ moles = \dfrac{mass}{molar \ mass}}[/tex]
Number of moles = [tex]\dfrac{6803.88 }{ 342}[/tex]
Number of moles of C12H22O11 = 19.894 moles
Since we've known the number of moles present in C12H22O11, the next thing to do is determine the number of molecules of sugar by using Avogadro's constant:
i.e.
number of moles of sugar = [tex]19.894 moles \times \dfrac{6.023 \times 10^{23}}{mol}[/tex]
= 1.198 × 10²⁵ molecules of C12H22O11
Now to determine the number of carbon atoms in 15 lbs, we have:
= number of carbon atoms × amount of molecules
= 12 × 1.198 × 10²⁵ carbon atoms
= 1.4376 × 10²⁶ carbon atoms
Therefore, we can conclude that there are 1.4376 × 10²⁶ carbon atoms present in 15 lbs of sugar, C12H22O11
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A chemist fills a reaction vessel with 9.47 atm nitrogen monoxide (NO) gas, 2.61 atm chlorine (C12) gas, and 8.64 atm nitrosyl chloride (NOCI) gas at a temperature of 25.0°C. Under these conditions, calculate the reaction free energy AG for the following chemical reaction:
2NO(g) + Cl2(g) = 2NOCI (g)
Use the thermodynamic information in the ALEKS Data tab. Round your answer to the nearest kilojoule.
Answer: The Gibbs free energy change of the reaction is 2.832 kJ.
Explanation:
The relationship between Gibbs free energy change and reaction quotient of the reaction is:
[tex]\Delta G^o=-RT\ln Q_p[/tex]
where,
[tex]\Delta G^o[/tex] = Gibbs free energy change
R = Gas constant = 8.314 J/mol.K
T = temperature = [tex]25^oC=298K[/tex]
[tex]Q_p[/tex] = reaction quotient = [tex]\frac{p_{NOCl}^2}{(p_{NO}^2)\times (p_{Cl_2})}[/tex]
We are given:
[tex]p_{NOCl}=8.64atm\\p_{NO}=9.47atm\\p_{Cl_2}=2.61atm[/tex]
Putting values in above equation, we get:
[tex]\Delta G^o=-(8.314)\times 298K\times \ln (\frac{(8.64)^2}{(9.47)^2\times (2.61)})\\\\\Delta G^o=-8.314\times 298\times (-1.143)[/tex]
[tex]\Delta G^o=2831.86J=2.832kJ[/tex] (Conversion factor: 1 kJ = 1000 J)
Hence, the Gibbs free energy change of the reaction is 2.832 kJ.
The element least likely to obey the octet rule in forming chemical bonds is Group of answer choices oxygen. carbon. nitrogen. neon. fluorine.
Answer:
neon
Explanation:
The octet rule states that atoms of elements are stable when they possess 8 electrons on their outermost shell.
Hence, atoms of elements participate in chemical reactions in order to attain this octet structure (eight electrons in the outermost shell).
Neon is a noble gas and already has eight electrons in its outermost shell. Hence, neon is least likely to obey the octet rule.
When taking a measurement with a pH meter, keep the instrument in the _______storage solution or water until it is needed. Rinse the pH meter with
_______deionized water or acetone and gently pat dry. Place the meter in the sample solution, and record the measurement when the pH _______stabilizes or reaches the maximum value
Answer:
storage solution , deionized water, stabilizes
Explanation:
A pH meter is a scientific device or instrument that is used to measure the pH of a given aqueous solution thereby determining the nature of the solution whether it is acidic or basic or neutral.
While using the pH meter or taking the measurement using the pH meter --
it should be kept in a storage solution for effective working.Before using the device, it is rinsed with a deionized water and pat dry.Record the measurements when the pH meter stabilizes.In an exothermic chemical reaction:____.
A. The mass of the products is greater than the mass of the reactants.
B. The mass of the products is less then the mass of the reactants.
C. Heat is released as the reaction proceeds.
D. Heat is absorbed as the reaction proceeds.
Answer:
C
Explanation:
Think of 'exo' as exit and 'thermic' as relating to thermal energy/ heat. Thus, an exothermic release thermal energy as the reaction proceeds.
In an exothermic reaction, the total energy of the products is lesser than that of the reactants and ΔH (change in energy) is less than zero.
When heat is absorbed as the reaction proceeds, the chemical reaction is an endothermic reaction.
Indicate how the concentration of each species in the chemical equation will change to reestablish equilibrium after reactant or product is added.
2CO(g) + O2(g) ⇌ 2CO2
Answer:
Indicate how the concentration of each species in the chemical equation will change to reestablish equilibrium after reactant or product is added.
[tex]2CO(g) + O2(g) <=> 2CO2[/tex]
Explanation:
When the reactants concentration increases, then the equilibrium will shift towards products and when the concentration of products increases, then equilibrium will shift towards reactants.
So, increases in concentration of carbon monoxide (CO) shifts the equilibrium to favor the formation of carbondioxide.
Similarly increase in concentration of oxygen also favor the formation of product carbon dioxide.
Increase in concentration of CO2 favors the formation of CO and O2.
Decrease in product concentration also favors the formation of product.
Decrease in reactant concentration favors the formation of reactants only.
What is unit? Write down the units of mass, temperature and power
Explanation:
a single thing, person, or group forming part of a whole There are 36 units in my apartment building. the least whole number : one. a fixed quantity (as of length, time, or value) used as a standard of measurement An inch is a unit of length.mass=kilogram (kg)
temperature=kelvin
power=watt
hope it helps
stay safe healthy and happy..Each of the following reactions were in equilibrium when the pressure of their containers was doubled. Chose which way the reaction shifted after the pressure change:
2NH3 (g)㈠No(g) +3H2(g) [Select ]
2Na3 PO4 (aq) + 3CaCl2 (aq) ㈠ Ca3 (PO4 )2 (s) + 6NaCl(aq) [Select ]
2C0(g)+O2 (g)->2CO2 (g) [Select ]
2H1(g) ㈠ H2(g) + 12(g) Neither
Answer:
Each of the following reactions was in equilibrium when the pressure of their containers was doubled. Chose which way the reaction shifted after the pressure change:
2NH3 (g)->N2(g) +3H2(g)
2Na3 PO4 (aq) + 3CaCl2 (aq) -> Ca3 (PO4 )2 (s) + 6NaCl(aq)
2CO(g)+O2 (g)->2CO2 (g)
2HI(g) -> H2(g) + I2(g)
Explanation:
Effect of pressure on equilibrium:
When pressure is increased on an equilibrium system,then equilibrium will shift in such a direction towards less number of moles of substrates.
For the first system,
2NH3 (g)->N2(g) +3H2(g)
increase in pressure,shifts the equilibrium towards the left side that is the formation of ammonia is favored.
For the second reaction:
2Na3 PO4 (aq) + 3CaCl2 (aq) -> Ca3 (PO4 )2 (s) + 6NaCl(aq)
The quilibrium will shift towards right.
Becuase right side less number of moles of substrates are there.
2CO(g)+O2 (g)->2CO2 (g)
For this system,the equilibrium will shift towards right side that is formation of CO2 gas is favored.
For the last system,
2HI(g) -> H2(g) + I2(g)
there is no effect of pressure.
Becuase the number of moles of substrates are same on both sides.
When we react a weak acid with a strong base of equal amounts and concentration, the component of the reaction that will have the greatest effect on the pH of the solution is: Select the correct answer below:_________
a. the reactant acid
b. the reactant base
c. the conjugate acid of the strong base
d. the conjugate base of the weak acid
Answer:
d. the conjugate base of the weak acid
Explanation:
The strong base (BOH) is completely dissociated in water:
BOH → B⁺ + OH⁻
The resulting conjugate acid (OH⁻) is a weak acid, so it remains in solution as OH⁻ ions.
By other hand, the weak acid (HA) is only slightly dissociated in water:
HA ⇄ H⁺ + A⁻
The resulting conjugate base (A⁻) is a weak base. Thus, it reacts with H⁺ ions from water to form HA, increasing the concentration of OH⁻ ions in the solution.
Therefore, the resulting solution will have a pH > 7 (basic).
from the following equation in which decomposition of CaCO3 takes place, give your justification. CaCO3 gives Ca +CO2
Answer:
CaCO₃(s) => CaO(s) + CO₂(g) ... GpIIA Decomp
Explanation:
Metallic Carbonates decompose into a metallic oxide and carbon dioxide.
Examples:
Na₂CO₃(s) => Na₂O(s) + CO₂(g) ... GpIA Decomp
MgCO₃(s) => MgO(s) + CO₂(g) ... GpIIA Decomp
Suppose of sodium iodide is dissolved in of a aqueous solution of potassium carbonate. Calculate the final molarity of sodium cation in the solution. You can assume the volume of the solution doesn't change when the sodium iodide is dissolved in it. Round your answer to significant digits.
Answer:
0.2762M Na+ in the solution
Explanation:
2.07g of sodium iodide Is Dissolved In 50.ML Of A 0.30M...
To solve this question we need to find the moles of sodium iodide, NaI, that are the same than the moles of sodium cation, Na+. The volume in liters of the solution is 0.050L. The molarity is:
Moles NaI = Moles Na+ -Molar mass NaI: 149.89g/mol-
2.07g NaI * (1mol / 149.89g) = 0.01381 moles NaI = Moles Na+
Molarity:
0.01381 moles Na+ / 0.0500L =
0.2762M Na+ in the solution
Many reactions involve a change in hybridization of one or more atoms in the starting material. In this reaction, determine the hybridization of the indicated atoms in the organic starting material, and determine if they have changed hybridization during the reaction.
Answer:
Please find the complete question and its solution file in the attachment.
Explanation:
The blank is the accepted form of gathering and reporting information within the science community.
Answer:
Scientific method.
Explanation:
Scientific method is the way taken to acquire scientific knowledge. It includes experiments, statistical analysis of existing data, and all kinds of observations of the world around us, while theoretical research is based on deriving certain theories about the world from basic principles, in a mathematical or logical way. The scientific method applies to both types of research, and emphasizes that scientific research is objective, that it can be verified by other scientists, and that knowledge is not acquired without context, but in a way that leads to a greater understanding of previous research and the world. we live in. To contribute to this, researchers are expected to clearly record both their findings and the methods they use to arrive at the results.
4019K Express your answer as a nuclear equation.
Answer:
[tex]_{19} ^{40} K[/tex] → [tex]_{20} ^{40} Ca[/tex] + [tex]_{-1} ^{0} e[/tex] + ¯v
Explanation:
[tex]_{19} ^{40} K[/tex] is an unstable potassium isotope which has the capacity to undergo beta decay. During the decay process, it transforms to calcium atom with a release of beta particle and an antineutrino.
The required nuclear equation is:
[tex]_{19} ^{40} K[/tex] → [tex]_{20} ^{40} Ca[/tex] + [tex]_{-1} ^{0} e[/tex] + ¯v
The calcium formed due to this process is a stable atom.
How many g of Al are required to produce 2.8 mol of Al2O3
Answer:
290 g Al₂O₃
General Formulas and Concepts:
Atomic Structure
Reading a Periodic TableMolesStoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
[Given] 2.8 mol Al₂O₃
[Solve] g Al₂O₃
Step 2: Identify Conversions
[PT] Molar Mass of Al: 26.98 g/mol
[PT] Molar Mass of O: 16.00 g/mol
Molar Mass of Al₂O₃: 2(26.98) + 3(16.00) = 101.96 g/mol
Step 3: Convert
[DA] Set up: [tex]\displaystyle 2.8 \ mol \ Al_2O_3(\frac{101.96 \ g \ Al_2O_3}{1 \ mol \ Al_2O_3})[/tex][DA] Multiply [Cancel out units]: [tex]\displaystyle 285.488 \ g \ Al_2O_3[/tex]Step 4: Check
Follow sig fig rules and round. We are given 2 sig figs.
285.488 g Al₂O₃ ≈ 290 g Al₂O₃
Topic: AP Chemistry
Unit: Atomic Structure
Which equation expresses the solubility product of Zn3(PO4)2?
a. Ksp = [Zn2+][PO43]
b. Ksp = [Zn2+]3 [PO43]2
c. Ksp = 6[Zn2+][PO43]2
d. Ksp = 108[Zn2+][PO43]2
⇒b. Ksp = [Zn2+]3 [PO43]2
Hope It Helps You ✌️
Plz!!!!Plz!!!!!help help
Answer:
false
Explanation:
category 1 is the worst
An unidentified gas is determined to be 24.0% carbon and 76% fluorine by mass. What is the empirical formula of this gas
Answer:
CF₂
Explanation:
Let's assume we have 100 g of the gas. If that were the case we'd have
24 g of C76 g of FNow we convert both masses into moles, using their respective molar mass:
24 g C ÷ 12 g/mol = 2 mol C76 g F ÷ 19 g/mol = 4 mol FWe can express those results as C₂F₄.
To determine the empirical formula we reduce those coefficients to the lowest possible integers, leaving us with CF₂.
All of the orbitals in the 3d subshell have a principal quantum number value of 3, an angular momentum quantum number of:_____.
Answer:
According to the four quantum numbers; magnetic quantum number is the same as angular momentum quantum number. so the answer is 5
Explanation:
for d subshell angular momentum "d" is assigned a value of : m= 2(range from negative to positive i.e, -2 to 2) so we have [ -2, -1 ,0, 1 , 2] which concludes to 5.