Answer:
Be2^+
Explanation:
Ionic diameter increases down the group. This implies that Be2^+ will have the smallest diameter.
This extremely small diameter makes Be2^+ to differ considerably from other ions of group 2 elements.
For instance, the compounds of beryllium are mostly covalent in nature.
Carbonic acid, H2CO3, has two acidic hydrogens. A solution containing an unknown concentration of carbonic acid is titrated with potassium hydroxide. It requires 22.9 mL of 1.430 M KOH solution to titrate both acidic protons in 54.2 mL of the carbonic acid solution.
Required:
a. Write a balanced net ionic equation for the neutralization reaction. Include physical states.
b. Calculate the molarity of the carbonic acid solution.
Answer:
a. H₂CO₃(aq) + KOH(aq) ⇄ K₂CO₃(aq) + H₂O(l)
b. 0.603 M
Explanation:
Step 1: Write the neutralization reaction
H₂CO₃(aq) + KOH(aq) ⇄ K₂CO₃(aq) + H₂O(l)
Step 2: Calculate the reacting moles of KOH
22.9 mL of 1.430 M KOH react.
0.0229 L × (1.430 mol/L) = 0.0327 mol
Step 3: Calculate the reacting moles of H₂CO₃
The molar ratio of H₂CO₃ to KOH is 1:1. The reacting moles of H₂CO₃ are 1/1 × 0.0327 mol = 0.0327 mol.
Step 4: Calculate the molarity of H₂CO₃
0.0327 moles of H₂CO₃ are in a volume of 54.2 mL. The molarity of H₂CO₃ is:
M = 0.0327 mol/0.0542 L = 0.603 M
It has been hypothesized that a chemical known as BW prevents colds. To test this hypothesis, 20,000 volunteers were divided into four groups. Each volunteer took a white pill every morning for one year. The contents of the pill taken by the members of each group are shown in the chart below. What is the independent variable in this experiment? *
1. % Developing Colds
2. Number of Volunteers
3. Grams of sugar
4. Grams of BW
Grams of BW
i think thats irtu9rgirg
Independent variable in an investigation is the variable is does not depends on any other variable and on which we can have the control. Hence, the grams of BW is the independent variable here.
What is independent variables?In an experiment the parameters which changes by control or depending on other changes are called variables. There are two kinds variables namely dependant and independent variables.
The dependant variables are those variable which depends upon other variables and whose changes are studying with respect to certain parameters.
Independent variables does not depends on other variable and can be controlled by the researcher. Here, we are studying the % of developing cold with respect to the amounts of BW. The changing variable is BW amount on which the percentage of cold depends.
Therefore, the independent variable is grams of BW and dependant variable is % development of cold.
To find more on independent variables, refer here:
https://brainly.com/question/29430246
#SPJ5
The mercury level in a capillary tube placed in a dish of mercury is actually below the surface of the mercury in the dish. Please choose the answer that best explains the phenomenon.a. Mercury flows freely and is incapable of clinging to the walls of the capillary tube. b. Mercury has an incredibly high density for a liquid, making it too heavy to climb the capillary tube, c. The cohesive forces of mercury are much stronger than its adhesive forces. The adhesive forces may be repulsive, causing the mercury level in the tube to be lower than the mercury in the dish. d. Mercury is a polar molecule. It creates incredibly high cohesive forces, which prevent the mercury from climbing the capillary tube.
Answer:
The cohesive forces of mercury are much stronger than its adhesive forces.
Explanation:
Cohesive forces are forces that exist between the particles that compose a substance while adhesive forces refer to forces that exist between the particles of a substance and those of another substance.
The cohesive forces in mercury far outweigh the adhesive forces between the mercury drops and glass. Hence when mercury is put into a capillary tube, its meniscus is convex because cohesive forces tend to draw the liquid mercury into a drop.
Hence, the surface tension in mercury makes the mercury in the capillary tube to fall below the height of the mercury in the dish.
Which of the following did you include?
The atoms in each ion are bonded together covalently to form a single unit.
The charge is distributed over the entire ion.
The formula of ammonium fluoride is NH4F.
The formula of potassium sulfate is K2SO
Answer:
The formula of ammonium fluoride is NH4F.
Explanation:
1 The atoms in each ion are bonded together covalently to form a single unit.
Wrong!
⇒ The atoms in an ion compound are linked together by an ionic bond.
2 The charge is distributed over the entire ion.
Wrong!
Ions have taken in or given up electrons. This happens in the atomic shell.
3 The formula of ammonium fluoride is NH4F.
Right!
4 The formula of potassium sulfate is K2SO
Wrong!
The formula for potassium sulfate is K2SO4.
plz help. with both will mark brainest
Answer:
The first one is balanced, but the second one is unbalanced.
Explanation:
Second one is unbalanced because there is an additional H and Cl on the right side. To fix it you would add a two in front of the HCl on the left side.
In this reaction: Mg (s) + I₂ (s) → MgI₂ (s)
If 3.34 moles of Mg react with 3.56 moles of I₂, and 1.76 moles of MgI₂ form, what is the percent yield?
Answer:
52.7%
Explanation:
The balanced equation for the reaction is given below:
Mg (s) + I₂ (s) → MgI₂ (s)
From the balanced equation above,
1 mole of Mg reacted with 1 mole of I₂ to produce 1 mole of MgI₂.
Next, we shall determine the limiting reactant. This can be obtained as follow:
From the balanced equation above,
1 mole of Mg reacted with 1 mole of I₂.
Therefore, 3.34 moles of Mg will also react with 3.34 moles of I₂.
From the illustration made above, we can see that only 3.34 moles out of 3.56 moles of I₂ reacted completely with 3.34 moles of Mg.
Therefore, Mg is the limiting reactant and I₂ is the excess reactant.
Next, we shall determine the theoretical yield of MgI₂.
In this case, the limiting reactant will be use because it will produce the maximum yield of MgI₂ as all of it is consumed in the reaction.
The limiting reactant is Mg and the theoretical yield of MgI₂ can be obtained as follow:
From the balanced equation above,
1 mole of Mg reacted to produce 1 mole of MgI₂.
Therefore, 3.34 moles of Mg will also react to produce 3.34 moles of MgI₂.
Thus, the theoretical yield of MgI₂ is 3.34 moles.
Finally, we shall determine the percentage yield of MgI₂ as follow:
Actual yield of MgI₂ = 1.76 moles
Theoretical yield of MgI₂ = 3.34 moles.
Percentage yield of MgI₂ =.?
Percentage yield = Actual yield /Theoretical yield × 100
Percentage yield = 1.76/3.34 × 100
Percentage yield of MgI₂ = 52.7%
HELP
Write the chemical name for each compound listed below.
1. NaCl
2. Al2O3
3. K25
4. CuBr2
5. Feo
HELPPP!!!
Write a definition for fluid that incorporates time
into a model of solids and liquids.
Answer:
Definition: Fluid that can act as a liquid or as a solid depending on the pressure applied on it.
Explanation:
A fluid that incorporates time in a solid and liquid model is a non-Newtonian fluid. This type of fluid can behave as a solid or as a liquid depending on the pressure that is applied on it. This is different from normal fluids that remain the same regardless of the pressure they are subjected to. In the case of non-Newtonian fluids, when submitted to pressure, they are presented as solids, but without pressure, they are presented as liquids. This feature can be seen even within the same system.
The # of electrons in S2- -34 is
Answer:
The answer is 16
Explanation:
Jeremy left his bike outside overnight. When he woke up in the morning, there were water drops on the seat. When he went to ride his bike after lunch, he saw the water drops had disappeared. Which statement best describes what happened to the water? (2 points) a The energy from the sun caused the water drops to condense. b The energy from the sun caused the water on the seat to boil. c The energy from the sun cooled the water, causing it to evaporate. d The energy from the sun heated the water, causing it to evaporate.
Answer:
d The energy from the sun heated the water, causing it to evaporate.
Explanation:
The correct description of what happened is that the energy from the sun heated the water and causes it to evaporate completely.
Evaporation is a phase change process in which liquid is converted to gases. This occurs when a liquid gains considerable amount of energy. The molecules then breaks free from the bond holding compound place.
Option A is wrong because the energy from the sun does not cause condensation i.e. change from gas to liquid. The water on the seat does not boil, it simply evaporates. So, option B is wrong. When heat energy is added, it does not cause cooling of water. So option C is wrong.pencil has a density of 14.5 g/mL and a volume of 5 mL. Calculate the mass in grams.
Answer:
The answer is 72.5 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question we have
mass = 14.5 × 5
We have the final answer as
72.5 gHope this helps you
which of the following is an acidic oxide?
A.CO
B.N2O
C.SO2
D.K2O
Answer:
C
Explanation:
On the graph, indicate the distance that corresponds to the bond length of the N2 molecule by placing an X on the horizontal axis.
Answer:
Check the image in the file attached below.
Explanation:
The objective of this question is to use the diagram provided to indicate the distance that corresponds to the bond length of the N2 molecule by placing X on the horizontal axis.
The bond length shows the distance of the bonds between the nuclei of the bonded atoms between the N2 molecule and O2 molecule. From the diagram, we can see that the bond length of O2 shows a greater tendency over the N2 molecule and it also have higher potential energy than the N2 molecule.
The distance corresponding to the bond length of N₂ is indicated in the attached graph.
Bond length represents/shows the bond distance between the atoms that are chemically bonded in the molecule ( N₂ ) . The bond distance ( average distance ) is measured from the nucleus of one binding atom toward another.
The bond length determines how easy or difficulty atoms bonded in a molecule can be separated. i.e. the longer the bond length the easier it is to separate chemically bonded atoms in a molecule.
Hence we can conclude that the distance corresponding to the bond length of N₂ is indicated in the attached graph.
Learn more : https://brainly.com/question/15436137
While ethanol CH3CH2OH is produced naturally by fermentation, e.g. in beer- and wine-making, industrially it is synthesized by reacting ethylene CH2CH2 with water vapor at elevated temperatures. A chemical engineer studying this reaction fills a 100L tank with 33.mol of ethylene gas and 16.mol of water vapor. When the mixture has come to equilibrium he determines that it contains 26.8mol of ethylene gas and 9.8mol of water vapor. The engineer then adds another 8.0mol of water, and allows the mixture to come to equilibrium again. Calculate the moles of ethanol after equilibrium is reached the second time. Round your answer to 2 significant digits.
Answer:
The value is [tex]k = 7.111 \ moles [/tex]
Explanation:
Generally the reaction between ethylene and water vapor is
[tex]CH_2CH_2_{(g)} \ \ \ +\ \ \ \ H_2O\ \ \ \rightarrow\ \ \ \ C_2H_5OH_{(g)}[/tex]
From the question the initial number of moles of ethylene is 33.mol
the initial number of moles of water vapor is 16.mol
So
At initial
[tex]CH_2CH_2_{(g)} \ \ \ +\ \ \ \ H_2O\ \ \ \rightarrow\ \ \ \ C_2H_5OH_{(g)}[/tex]
33.mol 16.mol 0 mols
Now at first equilibrium the number of moles of ethylene is 26.8mol
the number of moles of water vapor is 9.8mol
So the number of moles of ethanol is 33-26.8 = 6.2 mol
So at equilibrium
[tex]CH_2CH_2_{(g)} \ \ \ +\ \ \ \ H_2O\ \ \ \rightarrow\ \ \ \ C_2H_5OH_{(g)}[/tex]
26.8mol 9.8mol 6.2 mol
Generally the equilibrium constant is mathematically represented as
[tex]K = \frac{[C_2H_5OH]}{[CH_2CH_2] [H_2O]}[/tex]
Here [tex][C_2H_5OH][/tex] is the concentration of ethanol which is mathematically represented as
[tex][C_2H_5OH] = \frac{6.2 \ mol}{100L}[/tex]
=> [tex][C_2H_5OH] = 0.062 mol/L [/tex]
Also
[tex] [CH_2CH_2] = \frac{26.8 \ mol}{100L}[/tex]
[tex] [CH_2CH_2] = 0.268 mol/L[/tex]
Also
[tex][H_2O] = \frac{ 9.8 \ mol}{100L}[/tex]
[tex] [H_2O] = 0.098 mol/L[/tex]
So
[tex]K = \frac{0.062}{0.268* 0.098 }[/tex]
[tex]K = 2.3606 [/tex]
From the question we are told that 8 moles was added to ethylene
So volume of ethylene becomes 26.8 + 8 = 34.8 moles
So after the addition
[tex]CH_2CH_2_{(g)} \ \ \ +\ \ \ \ H_2O\ \ \ \rightarrow\ \ \ \ C_2H_5OH_{(g)}[/tex]
34.8mol 9.8mol 6.2 mol
At the second equilibrium
[tex]CH_2CH_2_{(g)} \ \ \ +\ \ \ \ H_2O\ \ \ \rightarrow\ \ \ \ C_2H_5OH_{(g)}[/tex]
(34.8- z)mol (9.8-z)mol ( 6.2+z) mol
Generally the equilibrium constant is mathematically represented as
[tex]K = \frac{[C_2H_5OH]}{[CH_2CH_2] [H_2O]}[/tex]
Here
[tex][C_2H_5OH][/tex] is now equal to
[tex][C_2H_5OH] = \frac{6.2+z}{100}[/tex]
[tex][CH_2CH_2]= \frac{ 34.8- z }{100}[/tex]
[tex][CH_2CH_2]= \frac{ 9.8-z }{100}[/tex]
So m
[tex]2.3606 = \frac{ \frac{6.2+z}{100}}{[ \frac{34.8- z }{100}] [\frac{ 9.8-z }{100}]}[/tex]
[tex]2.3606 = \frac{ \frac{6.2+z}{100}}{\frac{ z^2 -44.6 z + 341.04}{10000} }[/tex]
=> [tex]2.3606 = \frac{ 620 - 100z}{z^2 -44.6 z + 341.04}[/tex]
=> [tex]2.3606z^2 - 105.283 z + 805.05 =620 - 100z[/tex]
=> [tex]2.3606z^2 - 205.283 z + 185.059 = 0[/tex]
Multiply through by minus
=> [tex]2.3606z^2 -108.498z + 3336.7 = 0[/tex]
Solving this using quadratic equation
So [tex]z = 0.911[/tex]
Hence the number of moles of ethanol present at the second equilibrium is
[tex]k = 0.911 +6.2 [/tex]
[tex]k = 7.111 \ moles [/tex]
In the presence of strong acids, which of the oxygen atoms on the carboxyl group is preferentially protonated and why?
a. Protonation occurs at the carbonyl oxygen because the resulting conjugate acid i stabilized by resonance.
b. Protonation occurs at the carbonyl oxygen because the resulting conjugate base is stabilized by the inductive effect.
c. Protonation occurs at the hydroxyl oxygen because the resulting conjugate acid is stabilized by resonance.
d. Protonation occurs at the hydroxyl oxygen because the resulting conjugate base is stabilized by the inductive effect.
Answer:
Protonation occurs at the carbonyl oxygen because the resulting conjugate acid is stabilized by resonance.
Explanation:
The carboxyl group is an organic and a functional group that consists of a carbon atom that's singly bonded to a hydroxyl group and double-bonded to an oxygen atom.
In the presence of strong acids, protonation occurs at the carbonyl oxygen because the resulting conjugate acid is stabilized by resonance.
In the ionic compound KCL, which ion is the cation, and which is the anion? PLEASE HELP
Answer:
Potassium chloride, KCl , is an ionic compound formed by the electrostatic force of attraction that holds the potassium cations and the chlorine anions together
Explanation:
3. Which of the following molecules would want except to have a nonpolar covalent bond
Answer:
polar bonds are caused by different kind of atoms, because almost every atoms have different powers to attract electrons.
the answer will be the two same atoms, F2
Please help will give brainliest _________________________________________________________________________________________________________________________________________
Answer:
What subject is this for?
Explanation:
On the graph, which shows the potential energy curve of two N atoms, carefully sketch a curve that corresponds to the potential energy of two O atoms versus the distance between their nuclei.
Answer:
Explanation:
We are to carefully sketch a curve that relates to the potential energy of two O atoms versus the distance between their nuclei.
From the diagram, O2 have higher potential energy than the N2 molecule. Because on the periodic table, the atomic size increases from left to right on across the period, thus O2 posses a larger atomic size than N2 atom.
Therefore, the bond length formation between the two O atoms will be larger compared to that of the two N atoms.
Now
Selec
BI
Toda
OOOOOO
How and why do ionic bonds form? Check all of the boxes that apply
lonic bonds form between metal atoms and other metal atoms.
Ionic bonds form between metal atoms and nonmetal atoms
The more electronegative atoms transfer one or more electrons to the less electronegative atom
The less electronegative atoms transfers one or more electrons to the more electronegative atom,
The metal atom forms a cation and the nonmetal atom forms an anion
The attraction between ions with the same charge forms an ionic bond,
The attraction between ions with an opposite charge forms an ionic bond.
BLO
I lo
DONE
Elo
Yous
Answer:
✔️Ionic bonds form between metal atoms and nonmetal atoms.
✔️The less electronegative atoms transfers one or more electrons to the more electronegative atom
✔️The metal atom forms a cation and the nonmetal atom forms an anion.
✔️The attraction between ions with an opposite charge forms an ionic bond.
Explanation:
Ionic bond refers to the bond formation which occurs when there is complete and permanent transfer of electrons from one metal atom to another non-metal atom. The metals, which are electropositive (less electronegative) loose their electrons while the non-metals, which are less electropositive (more electronegative) gain the electrons.
When the metal atom looses electrons, they form cations(become positively charged) while non-metal atom forms anions (become negatively charged). When the opposite charges attract each other, they form ionic bond.
Answer:
✔️ Ionic bonds form between metal atoms and nonmetal atoms.
✔️ The less electronegative atoms transfers one or more electrons to the more electronegative atom.
✔️ The metal atom forms a cation and the nonmetal atom forms an anion.
✔️ The attraction between ions with an opposite charge forms an ionic bond.
Object A has a mass of 12g and a volume of 8cm3. object B has a mass of 20g and a volume of 8cm3 . which object has a greater density and by how much
Answer:
Object B has a density of 2.5 g/cm³ which is greater than object A by 1 g/cm³
Explanation:
Since we know that the formula for density is d=m/v, we can divide each mass by its corresponding volume to find the densities
12/8=1.5
20/8=2.5
So we know that object B has a greater density than object A by 1 g/cm³ (gram per cubic centimeter). Also the standard unit for density is kilograms per cubic meter but I used gram per cubic centimeter since they were the given units. 1cm=100m, 1000g=1km
Which property do solutions with high pH values have?
gives off hydrogen gas when reacted with metal
turns litmus paper red
tastes sour
feels slippery
Answer:
I would say turns litmus paper red.
Explanation:
I finished the quiz, and got it right! Hope this helps!
a. For a two-component alloy, derive the equations that convert the weight percent to atomic percent (for a two-element alloy).
b. Calculate the atomic fraction of Cu in an alloy that consists of 92.5 wt.% Ag and 7.5wt% Cu
Answer:
a. wt% A / Atomic Mass A / (wt% A / Atomic Mass A + wt% B / Atomic Mass B).
b. 11.74%
Explanation:
a. Weight percent is the mass of an element in 100g of the alloy. Atomic percent could be taken as the ratio between moles of an element and the total moles of the alloy.
Assuming a basis of 100g, the moles of A and B (The two elements in the alloy), are:
Moles A:
wt% A / Atomic Mass A
Moles B:
wt% B / Atomic Mass B
And atomic percent of A is:
wt% A / Atomic Mass A / (wt% A / Atomic Mass A + wt% B / Atomic Mass B)b. Atomic fraction of Cu in the alloy is (Molar mass Cu: 63.55g/mol; Molar mass Ag: 107.87g/mol):
7.25wt% / 63.55g/mol / (7.25wt% / 63.55g/mol + 92.5wt% / 107.87g/mol)
Atomic fraction Cu = 0.1174 = 11.74%
The use of water in a heat exchanger is taking advantage of water's A. high specific heat. B. significant expansion during boiling. C. solid state when frozen. D. polar molecular nature
Answer:
A. high specific heat.
Explanation:
Specific heat defines the heat or thermal capacity of a substance.
Water has a high specific heat which adds an advantage to a heat exchanger. Due to the high heat or thermal capacity of the water heat exchanger can transfer a huge amount of heat between two or more fluids.
Hence, the correct answer is "A. high specific heat."
Answer:
A. high specific heat.
Explanation:
which material should you use so that the area is cool in terms of temperture O asphalt O red bricks O concrete O soil O
Answer:
red bricks
Explanation:
right on edg 2020
Red bricks should you use so that the area is cool in terms of temperture. Therefore, option B is correct.
What are red bricks used for?Red bricks can be used in the construction of structures such as buildings, foundations, arches, pavement, and bridges. These can also be used for aesthetic purposes such as landscaping, face work, and a variety of other architectural purposes.
Traditional red bricks are saw to be more robust, and structures constructed with them are stronger than hollow block structures.Red brick can be warm, with rust or terracotta undertones. They could also be cool and more burgundy.
Thus, Red bricks should you use so that the area is cool in terms of temperture, option B is correct.
To learn more about the red bricks, follow the link;
https://brainly.com/question/14893671
#SPJ6
A gas has a volume of 300 mL and a pressure of 2 atm. What volume will the gas occupy when the pressure is
increased to 7 atm (total)?
Answer:
The answer is 85.71 mLExplanation:
The new volume can be found by using the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
where
P1 is the initial pressure
P2 is the final pressure
V1 is the initial volume
V2 is the final volume
Since we are finding the new volume
[tex]V_2 = \frac{P_1V_1}{P_2} \\[/tex]
We have
[tex]V_2 = \frac{300 \times 2}{7} = \frac{600}{7} \\ = 85.714285...[/tex]
We have the final answer as
85.71 mLHope this helps you
Which of the following BEST describes the main function of carbohydrates?
a
Speeding up chemical reactions
b
Fuel
c
Instructions for making proteins
d
Energy storage
What do scientists call all of the compounds that contain carbon and are found in living things?
organic
inorganic
acidic
nonacidic
Answer:
Organic
Explanation:
Edge student
Why do the leaves outside change colors?
Answer:
because the amount of pigments change as thee leaves prepare to fall from the trees
Calculate the pH of a 0.02 M solution of ascorbic acid ( K a1 = 7.9 × 10 –5; K a2 is 1.6 × 10 –12).
a.
2.9
b.
8.2
c.
11.8
d.
11.1
e.
5.8
Answer:
C
Explanation:
