conditions under which metals react with water​

Answers

Answer 1

Answer:

Reactions of Metals with Water

Metals with moderate to low reactivity react very slowly with water. However, they react moderately with steam when heated and give hydrogen gas and metal oxides. Metals low in the metal reactivity series do not react with water even at high temperature.

Explanation:

Order of reactivity                     Metal               Reactions with water or steam

↑                                           sodium (Na)         Vigorous reaction with cold water

↓                                        calcium (Ca)    Less vigorous reaction with cold water

least reactive           magnesium (Mg)    Slow reaction with cold water, vigorous                                                                                                   .                                                                 with hot water


Related Questions

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.

Answers

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

Answers

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.

Help plz!!!!!!!!!!!!!!!

Answers

Answer:

Albert Einstein proposed that a beam of light is not a wave propagating through space, but a collection of discrete wave packets—photons.

Explanation:

So the right answer is the first one.

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

Answers

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%

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

Answers

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.

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

Answers

Answer:

C

Explanation:

HELPPP!!!
Write a definition for fluid that incorporates time
into a model of solids and liquids.

Answers

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.

Which of the following best describes the structure of a nucleic acid?

a
Carbon ring(s)
b
Globular or fibrous
c
Single or double helix
d
Hydrocarbon(s)

Answers

it’s definitely C! brainlest please i need points so sorry if it’s wrong i guessed A

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.

Answers

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

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.

Answers

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.

Why do the leaves outside change colors?

Answers

Answer:

because the amount of pigments change as thee leaves prepare to fall from the trees

pencil has a density of 14.5 g/mL and a volume of 5 mL. Calculate the mass in grams.

Answers

Answer:

The answer is 72.5 g

Explanation:

The mass of a substance when given the density and volume can be found by using the formula

mass = Density × volume

From the question we have

mass = 14.5 × 5

We have the final answer as

72.5 g

Hope this helps you

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.

Answers

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]

The # of electrons in S2- -34 is

Answers

Answer:

The answer is 16

Explanation:

In the ionic compound KCL, which ion is the cation, and which is the anion? PLEASE HELP

Answers

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:

On the graph, indicate the distance that corresponds to the bond length of the N2 molecule by placing an X on the horizontal axis.

Answers

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.

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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?

Answers

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%

3. Which of the following molecules would want except to have a nonpolar covalent bond

Answers

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

which of the following is an acidic oxide?
A.CO
B.N2O
C.SO2
D.K2O​

Answers

Answer:

C

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

Answers

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;

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I Need Help Please ?

Answers

Answer:

Not sure dude goodluck

Explanation:

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

Answers

Turns litmus paper red, I did this experiment in 7th grade lol

Answer:

I would say turns litmus paper red.

Explanation:

I finished the quiz, and got it right! Hope this helps!

plz help. with both will mark brainest

Answers

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.

What is the standard enthalpy of the reaction:

2 NO(g) + O2(g) → 2 NO2(g)?

Answers

Answer:

-116.2 kJ

Explanation:

What do scientists call all of the compounds that contain carbon and are found in living things?

organic
inorganic
acidic
nonacidic

Answers

Organic is the answer

Answer:

Organic

Explanation:

Edge student

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.

Answers

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.

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

Answers

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

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

Answers

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:

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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.

Answers

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.

Please help will give brainliest _________________________________________________________________________________________________________________________________________

Answers

Answer:

What subject is this for?

Explanation:

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