If3.91 potassium metal is
allowed to react with oxygen,
O2, the reaction yields 7.11g of k2o.
How much oxygen was reacted?

Answers

Answer 1
K20 because 3.91=
O2=
7.11g=

Related Questions

How would you classify a creepy
crawly with no vertebrae and more
than 6 jointed legs?
Rileach
s. snake
T. spider
v.cockroach

Answers

Answer:

T

Explanation:

A Spider is a creepy crawly with no vertebrae and more than 6 jointed legs.

The Spider belongs to the class Arachnida . The Spider can be referred to as a non-vertebrates hence , they don't have a vertebrae(backbone).

The Spider and Cockroach are both non-vertebrates but with different pairs of legs. A cockroach is belongs to the class Insecta in which those under this class have only six jointed legs.

The Spider has eight jointed legs which is more than six and is a characteristic of Arachnids.

A snake on the other hand is a vertebrate which exempts it from being the answer.

Read more on https://brainly.com/question/18770888

I Need Help Please ?

Answers

Answer:

Not sure dude goodluck

Explanation:

Please help will give brainliest _________________________________________________________________________________________________________________________________________

Answers

Answer:

What subject is this for?

Explanation:

Calculate the concentration of buffer components present in 210.00 mL of a buffer solution that contains 0.300 M NH4Cl and 0.300 M NH3 immediately after the addition of 1.00 mL of 6.00 M HNO3.

Answers

Answer:

[NH3] = 0.270M

[NH4Cl] = 0.327M

Explanation:

The HNO3 will react with the weak base, NH3, as follows:

HNO₃ + NH₃ → NH₄⁺ + NO₃⁻

Initial moles of each specie of the buffer:

NH3 = NH4⁺ 0.210L * (0.300mol/L) = 0.063moles

The moles added of HNO3 = Additional moles of NH4Cl and the moles substracted of NH3:

0.001L * (6mol / L) = 0.006 moles.

After the addition:

Moles NH3 = 0.063mol - 0.006mol = 0.057moles

Moles NH4Cl = 0.063mol + 0.006mol = 0.0069moles

And their concentrations are:

[NH3] = 0.057moles / 0.211L = 0.270M

[NH4Cl] = 0.069moles / 0.211L = 0.327M

How many milliliters of 0.500 M HBr would be required to react with 40.0 mL of 0.300 M Ca(OH)2?

Answers

Answer:

48dm³

Explanation:

Given reaction:

                  Ca(OH)₂ + 2HBr →  CaBr₂ + 2H₂O

Parameters:

Concentration of HBr = 0.5M

 Volume of Ca(OH)₂ = 40mL

 Concentration of  Ca(OH)₂ = 0.3M

Solution:

To solve this problem, we are going to use the mole concept. We solve from the known specie to the unknown.

 We first find the number of moles of the known specie which is the Ca(OH)₂ ;

                number of moles  = concentration x volume

                number of moles  = 0.3 x 40 x 10⁻³ = 0.012moles

From the reaction equation;

           1 mole of Ca(OH)₂  requires 2 moles HBr

          0.012 moles of Ca(OH)₂ will require 0.012 x 2  = 0.024moles of HBr

Now,

 To find the volume of HBr;

          Volume  = [tex]\frac{number of moles }{concentration}[/tex]

          Volume  = [tex]\frac{0.024}{0.5}[/tex]   = 0.048dm³

In mL;

       Volume 0.048 x 1000 = 48dm³

The table below gives the numbers of protons, electrons, and neutrons in four atoms.
Number of neutrons
Number of protons
19
Number of electrons
9
Atom
1
12
3
collo
18
10
9
9
9
10
4
19
Based on the table, which atom has a charge of -12
O 1
O 2
03
4

Answers

Answer:

THE ANSWER IS D UR WELCOME.

Explanation:

Select the word that is incorrect in the paragraph and replace it with a word which makes the statement correct:
Group 2 elements have two valence electrons in their outer shell and are considered metals. In order to form an ion, a Group 2 element will
gain two electrons and form a cation.

Answers

A group 2 element will lose two electrons and form an anion.

Ions can be made by single element or covalently bonded group of elements. The covalently bonded group of elements is called polyatomic ions or polyatomic atoms. In order to form an ion, a Group 2 element will loose two electrons and form a cation.

What is Ions?

Any species that contain charge whether it is positive charge or negative charge is called ions. The example of polyatomic ions are sulfate, phosphate, nitrate etc.

Cation is the species that loose electron and attain positive charge while anion is a species which gain electron and attains negative charge so when anion and cation combine in fixed ration the the overall charge of the molecule is zero that is molecule is neutral, the charge over cation and anion is also called oxidation state.  In order to form an ion, a Group 2 element will loose two electrons and form a cation.

Therefore, in order to form an ion, a Group 2 element will

loose two electrons and form a cation.

To learn more about ions, here:

https://brainly.com/question/13692734

#SPJ2

) What would be the effect on the molarity of the NaOH solution if some of the water evaporated from the Florence flask after the NaOH solution was standardized with the KHP

Answers

Answer:

The effect is the increasing of the molar concentration.

Explanation:

When you standarize a solution of NaOH with KHP you are establish its molar concentration (That is the amount of moles of NaOH per liter of solution).

If you evaporated some water of the solution, you are increasing its concentration because volume is decreasing doing the amount of moles per liter increasing.

What specific portion of the gill is used to increase surface area though which gas (oxygen and carbon dioxide) exchange take place?

Answers

Answer:

gill lamellae

Explanation:

Gills  in fishes are structures that permit fish to carry out gaseous exchange in water.  Fishes exchange gases  such as oxygen and carbon dioxide using gills.

Fish gills carry out their activity mainly through its major component called the  gill lamellae. These are comb-like filaments which help increase the surface area of the gills in order to facilitate gaseous exchange

A sample of sodium bicarbonate is placed in an evacuated container at allowed to reach equilibrium. What will be the total pressure?

Answers

Complete Question

Sodium carbonate, Na2CO3(s), can be prepared by heating sodium bicarbonate, NaHCO3(s).

2NaHCO3(s) ------> Na2CO3(s) + CO2(g) + H2O(g) Kp = 0.23 at 100oC

If a sample of NaHCO3 is placed in an evacuated flask and allowed to achieve equilibrium at 100oC, what will the total gas pressure be?

Answer:

The value is  [tex]P_T  = 0.959 \  atm [/tex]

Explanation:

From the question we are told that

   The equation is  

[tex]2NaHCO_3_{(s)} \rightarrow  Na_2CO_3_{(s)} + CO2_{(g)} + H2O_{(g)}[/tex]

Generally the equilibrium partial pressure is mathematically represented as

    [tex]K_p =  P_{CO_2} + P_{H_2O}[/tex]

Here  

   [tex] P_{CO_2} \ and  \  P_{H_2O}[/tex] are partial  pressures of  [tex] CO_2 \ and  \ H_2O [/tex] gases

Note: when writing the formula for equilibrium partial pressure we consider only the gas in the reaction

Let assume that    

    [tex]P_{CO_2} =  a[/tex]

Generally  [tex]P_{CO_2} = P_{H_2O}[/tex] since they are both products of the reaction

  So  

       [tex]K_p =  a^2 [/tex]

From the question we are told that [tex]K_p =  0.23 [/tex]

So  

     [tex] 0.23=  a^2 [/tex]

=>  [tex] a = \sqrt{0.23} [/tex]

=>  [tex] a = \sqrt{0.23} [/tex]

=>  [tex] a = 0.4796  \ atm [/tex]

So

     [tex]P_{CO_2} =  0.4796  \ atm[/tex]

and

      [tex]P_{H_2O} =  0.4796  \ atm [/tex]

So the total pressure is

      [tex]P_T  =  0.4796  +  0.4796[/tex]

=>   [tex]P_T  = 0.959 \  atm [/tex]

Which statements best describe half lives of radioactive isotopes

Answers

You should also add the statements

Answer:

The half-life varies depending on the isotope.

Half-lives range from fractions of a second to billions of years.

The half-life of a particular isotope is constant.

Explanation:

Make sure you add the options

What is the pH of a solution made by mixing 0.050 mol of NaCN with enough water to make a liter of solution

Answers

Answer:

pH = 11

Explanation:

The equilibrium of a weak base as NaCN in water is:

NaCN(aq) + H₂O(l) ⇄ OH⁻(aq) + Na⁺(aq) + HCN(aq)

And kb, the equilibrium constant, is:

Kb = [OH⁻] [HCN] / [NaCN]

Where Kb of NaCN is 2.04x10⁻⁵

In the beginning, the [NaCN] is 0.050mol / L = 0.050M.

Both [OH⁻] and [HCN] are produced from this equilibrium, and its concentration is X, that is:

2.04x10⁻⁵ = [X] [X] / [0.050M]

1.02x10⁻⁶ = X²

X = 1x10⁻³ = [OH⁻]

As pOH = - log [OH⁻]

pOH = 3.00

And pH = 14 - pOH

pH = 11

assuming the temperature is held constant, how could you increase the pressure inside a container by a factor of 3

Answers

The pressure can be increased by a factor of 3 by decreasing the volume by a factor of 3.

Ideal Gas Equation:

Given that the temperature of the system is held constant. So it implies that it is an isothermal process.

Now we know that the ideal gas equation is given by:

PV = nRT

where, P is the pressure

V is the volume

n is the number of moles

R is the gas constant, and

T is the temperature

Assuming n is constant, R is universal as constant, so if T is also constant, then:

PV = constant

So if P becomes 3P. that is the pressure increased by a factor of 3, then V must become V/3, so that: (3P)(V/3) = PV = constant.

Learn more about ideal gas:

https://brainly.com/question/11676583?referrer=searchResults

How many valence electrons must a lithium atom lose to obtain a complete valence shell?
A. one
B. two
C. three
D. four

Answers

Answer:

C. three

Explanation:

Calculate the number of grams of CuSO4 found in 3.29 mL of a 4.00 M CuSO4 solution. ______ grams CuSO4

Answers

Answer:

0.0132 g CuSO₄

General Formulas and Concepts:

[tex]\text{Molarity}=\frac{\text{moles of solute}}{\text{liters of solution}}[/tex]

Explanation:

Step 1: Define variables

3.29 mL

4.00 M CuSO₄

x g CuSO₄

Step 2: Define conversions

1000 mL = 1 L

Step 3: Solve

Convert mL to L:                         [tex]\text{3.29 mL}(\frac{\text{1 L}}{\text{1000 mL}} )[/tex] = 0.00329 LSubstitute:                                   [tex]\text{4.00 M} \ CuSO_4=\frac{\text{x g} \ CuSO_4}{\text{0.00329 L}}[/tex]Multiply both sides by L:            [tex]\text{0.01316} \ CuSO_4=\text{x g} \ CuSO_4[/tex]Rewrite:                                       [tex]x = 0.01316 \ g \ CuSO_4[/tex]

Step 4: Simplify

We are given 3 sig figs.

0.01316 g CuSO₄ ≈ 0.0132 g CuSO₄

In carbon dioxide (CO2), there are two oxygen atoms for each carbon atom. Each oxygen atom forms a double bond with carbon, so the molecule is formed by two double bonds.

Two double bonds means that the total number of electrons being shared in the molecule is

Answers

Answer:

The Answer is eight.

Explanation:

Sorry if it's too late and it doesn't help! But I hope you have a magnificent day! :3

Answer:

8

Explanation:

I had this question on my quiz and got it right.

A balloon contains 1.1 L of gas at a pressure of 0.80 atm. How will the volume
change if the pressure is increased to 2.0 atm?

Answers

Answer:

Final volume  = 0.44 L

Explanation:

Given data:

Initial volume of balloon = 1.1 L

Initial pressure = 0.80 atm

Final volume = ?

Final pressure = 2.0 atm

Solution:

The given problem will be solved through the Boly's law,

"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"

Mathematical expression:

P₁V₁ = P₂V₂

P₁ = Initial pressure

V₁ = initial volume

P₂ = final pressure

V₂ = final volume  

Now we will put the values in formula,

P₁V₁ = P₂V₂

0.80 atm × 1.1 L = 2.0 atm × V₂

V₂ = 0.88 atm. L/ 2.0 atm

V₂ = 0.44 L

Entropy is a measure of
1.
accuracy
2.
precision
3.
the disorder of a system
4.
the attraction of a nucleus for an electron

Answers

Answer:

The answer is actually 3. The disorder of a system.


1. What 2 subatomic particles have charges? List the particle name and its charge.

Answers

Answer: Proton - positive charge (+)

Neutron - neutral charge (0)

Electron - negative charge (-)

Explanation:

In Fig 1-2, how should the length indicated by the arrow along the ruler be recorded?

Answers

Answer:

C. 0.35cm

Explanation:

The length indicated by the arrow along the ruler should recorded be recorded as "0.35cm".

This is correct because when counting the measurement on the ruler, the first line on the ruler is 0.1cm, the second line is 0.2cm, and so on. The spaces between each line is 0.05cm. So, the arrow is pointing on the space between 0.3cm and 0.4cm.

Therefore, 0.3cm + 0.05cm = 0.35cm.(answer).

what element has a higher ionization energy carbon or silicon

Answers

Carbon has the highest ionization energy
Carbon has the highest ionization energy in the group. The ionization energy for silicon is lower because the outermost electrons for silicon (3p) are further away from the nucleus than those of the 2p level for carbon.

which two options are examples of chemical changes?
A. A shinny metal bar glows red and expands when heated.

B. white piece of paper turns black and gives off a smell when burned

C. When two clear colorless liquids are mixed together, a white solid forms

D. A white powder mixed with a clear, colorless liquid makes a solution that is also clear, colorless liquid

Answers

Answer:

B

Explanation:

It's the only thing that actually changes into something different and when u burn it it makes chemicals

My made-up polyatomic ion goldate acts a lot like chlorate (it has the same charge and the same number of oxygens). What would the name be for the acid, HG004(aq)?
a. Hydrogen diogoldate
b. Goldous acid
c. Goldic acid
d. Pergoldic acid
e. None of these

Answers

Answer:

d. Pergoldic acid

Explanation:

chlorate = ClO₃⁻

Goldate GoO₃⁻

On this basis we can infer that HClO₄ and HGoO₄ will be similar .

HClO₄ is called perchloric acid , hence HGoO₄ will be called pergoldic acid.

a. Describe the molecule chlorine dioxide, CIO in terms of three possible resonance structures.
b. Do any of these resonance structures satisfy the octet rule for every atom in the molecule? Why or why not?

Answers

Answer:

See explanation

Explanation:

The compound ClO2 has 19 valence electrons.  ClO2 is a bent molecule with tetrahedral electron pair geometry but has two  lone pairs of electrons. This is indicated by the presence of four electron pairs on the outermost shell of the central atom.

The molecule has an odd number of valence electrons, hence, it is generally regarded as a paramagnetic radical. None of the proposed Lewis structures for the molecule is satisfactory because none of them obeys the octet rule.

From the images attached, one can easily see that the electron dots around the oxygen and chlorine atoms does not satisfy the octet rule in all the resonance structures shown.

The Earth can gain or lose matter. True False​

Answers

Answer:

True

Explanation:

According to some calculations, the Earth is losing 50,000 metric tons of mass every single year, even though an extra 40,000 metric tons of space dust converge onto the Earth's gravity well, it's still losing weight.

Answer:

true

Explanation:

Hydrogen sulfide decomposes according to the following reaction, for which Kc=9.30E-8 at 700 degrees Celsius. 2 H2S(g) --> 2 H2(g) + S2(g) If 0.29 moles of H2S is placed in a 3.0-L container, What is the equilibrium concentration of H2(g) at 700 degrees Celsius?

Answers

Answer: The equilibrium concentration of [tex]H_2(g)[/tex] at 700 degrees Celsius is 0.0012 M

Explanation:

Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as [tex]K_c [/tex]

Moles of  [tex]H_2S[/tex] = 0.29 mole

Volume of solution = 3.0 L

Initial concentration of [tex]H_2S[/tex] = [tex]\frac{0.29mol}{3.0L}=0.097M[/tex]

The given balanced equilibrium reaction is,

                    [tex]2H_2S(g)\rightleftharpoons 2H_2(g)+S_2(g)[/tex]

         Initial conc.         0.097 M           0M          0M

At eqm. conc.    (0.097-2x) M            (2x) M   (x) M

The expression for [tex]K_c[/tex] is written as:

[tex]K_c=\frac{[H_2]^2\times [S_2]}{[H_2S]^2}[/tex]

[tex]K_c=\frac{(2x)^2\times x}{(0.097-2x)^2}[/tex]

[tex]9.30\times 10^{-8}=\frac{(2x)^2\times x}{(0.097-2x)^2}[/tex]

[tex]x=0.00060[/tex]

Equilibrium concentration of [tex][H_2][/tex]= 2x= [tex]2\times 0.00060=0.0012M[/tex]

A block of lead weighs 11.3 grams. How many atoms of lead are in this sample?
• Use 6.022 x 1023 mol
for Avogadro's number.​

Answers

Answer:

To get the number of atoms in this sample, we first need the number of moles of lead in 11.3 grams

Number of moles of Lead:

Molar mass of lead = 207 grams / mol

Number of moles  = given mass / molar mass

Number of moles = 11.3 / 207

Number of moles = 0.05 moles

Number of atoms of lead in 11.3 gram sample:

Number of atoms = Number of moles * avogadro's number

Number of atoms = 0.05 * 6.022 * 10²³

Number of atoms = 5 * 10⁻² * 10²³ * 6.022

Number of atoms = 30.11 * 10²¹

11.3 g block of lead contains 3.29×10²² atoms

From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.022×10²³ atoms. Thus,

1 mole of lead = 6.022×10²³ atoms

Recall:

1 mole of lead = 207 g

Thus,

207 g of lead = 6.022×10²³ atoms

With the above information in mind, we can obtain the number of atoms in 11.3 g block of lead as illustrated below:

207 g of lead = 6.022×10²³ atoms

Therefore,

11.3 g of lead = (11.3 × 6.022×10²³) / 207

11.3 g of lead = 3.29×10²² atoms

Thus, 11.3 g block of lead contains 3.29×10²² atoms

Learn more: https://brainly.com/question/9758372

2. Which gas is NOT an efficient greenhouse gas?

A. Helium

B. Methane

C. Carbon dioxide

D. Water vapor

Answers

Answer:

helium

Explanation:

remaining three are efficient gas

Among the options given below, helium is not an efficient greenhouse gas. Thus, the correct option for this question is A.

What do you mean by Greenhouse gases?

Greenhouse gases are those gases that significantly allow solar radiation in order to enter but prevent the escape of heat radiations of longer wavelengths. The names of common greenhouse gases are carbon dioxide, methane, nitrous oxide, CFCs, etc.

According to the context of this question, the presence of these gases in the atmosphere is responsible for the phenomenon of keeping the earth warm. This is known as Greenhouse effect. These gases stimulate the phenomenon of global warming.

Therefore, among the options given below, helium is not an efficient greenhouse gas. Thus, the correct option for this question is A.

To learn more about Greenhouse gases, refer to the link:

https://brainly.com/question/20349818

#SPJ2

Which set of procedures would be best to follow when separating a mixture of sand, salt, and water?

Answers

Answer:

Pour the mixture through a filter to separate the sand, then evaporate the liquid to separate the salt.

Explanation:

There are various methods used to separate single substances from a mixture. The method adopted depends upon the type of mixture and the ingredients used in it. According to the given question, the mixture comprises of sand, salt and water. Here, the first process will be the process of filtration. Through filtration, the salt-water solution and sand can be separated. Salt-water solution can be separated by the process of evaporation in which sat and water will be separated individually.

The numbers represent the change in energy for a chemical reaction. They are calculated by subtracting the energy of products from the energy of reactants. Which number would result from an endothermic reaction?

Answers

Answer:

800

Explanation:

took the test and got it right

The numbers represent the change in energy for a chemical reaction. They are calculated by subtracting the energy of products from the energy of reactants. 800 would result from an endothermic reaction.Therefore, the correct option is D.

What are the various types of reactions?

             

There are different types of reactions, such as the endothermic reaction, where the energy is used for the product's formation, and the exothermic reaction.

The energy is released in an exothermic reaction, resulting in a negative result, whereas the energy is used in an endothermic reaction, resulting in a positive result.

Any chemical reaction that absorbs heat from its surroundings is an endothermic reaction. The absorbed energy serves as the activation energy for the reaction to take place.

Thus, 800 would result from an endothermic reaction, the correct option is D.

Learn more about the types of reactions here.

brainly.com/question/23184814

#SPJ2

Your question is incomplete, most probably your question was

The numbers represent the change in energy for a chemical reaction. They are calculated by subtracting the energy of products from the energy of reactants. Which number would result from an endothermic reaction?

–212

0

-1

800

Other Questions
I need to simplify this but if how can someone please help ASAP PLEASE HELPThe duty of ___ is to give their votes for President.A) CongressB) citizensC) SenatorsD) RepresentativesE) electors Taken as a whole, the reasoning and evidence in the passage primarily defend a claim regarding? what best describes the relationship between the lines with equations y + 3x = 10 and 2y = -6x + 4? Question 3. Separation of powers means that governmental power isdivided among different groups, such as the executive, judicial, and *O military branchesroyal brancheslegislative branches.O religious branch Alonzo earns 8% commission on vacuum cleaner sales. This past month, Alonzo sold 70 units at $150.00 each. How much did Alonzo make in commissions for the past month? Explain how you found your answer. nosotros___ en el mar. (baarse) Assume that if Ivanhoe Water accepts Cliftons offer, the company can use the freed-up manufacturing facilities to manufacture a new line of growing lights. The company estimates it can sell 80,410 of the new lights each year at a price of $13. Variable costs of the lights are expected to be $10 per unit. The timer unit supervisory and clerical staff would be transferred to this new product line. Calculate the total relevant cost to make the timer units and the net cost if they accept Clifton's offer. 15 points to Answer this!! Really need help this Important!! Imagine you work in the medical records department of a large clinic. When you check the voicemail one morning, there is a message from Mrs. Jones, a patients wife. She is unhappy because the office has refused to release her husbands medical records to her. Releasing the records to Mrs. Jones would be a violation of the patients privacy.You must respond to Mrs. Jones. Decide what medium you will use to most effectively communicate your message (phone, email, text message, etc.) and compose the response you will provide to her. The timeline shows key dates in the womens suffrage movement in Washington.In what year did women in Washington permanently win the right to vote?1883188718881910 On another training ride, Jana bikes 15 miles in 50 minutes. Explain how youcould find the number of miles she bikes in 1 hour Which groups comprise the largest percentage of Mexicos population? Because its popularity, the play's concept also became a television series, which lasted five years.Which argument does this sentence support?OA. The show would not have happened without the movie..The storyline of The Odd Couple is an enduring classic.OC. The Odd Couple show lacked Neil Simon's wit.ODThe play was more successful than the television show.PLEASE HELP . Trade flourished in the Assyrian Empire because A. people craved Asian spices. B. they invented the wheel. C. they wanted to expand their empire. D. there was a vast network of safe roads. which point is the image of P describe what the industrial revolution was about? Sitting down at her favorite restaurant, Aliyah is looking at the menu trying to figure out what she would like to have. She notes an asterisk next to one of the dishes and finding the note at the bottom of the menu, it says, Although we will cook to order, be aware that consuming this dish raw or undercooked may increase your risk of contracting salmonella. Which menu item is MOST likely being referenced here?A. Eggs BenedictB. Blackened SalmonC. Chocolate CakeD. Spinach Lasagna imagine you are father, write a letter to your son expressing your feelings and emotions after his heavenly departure Find the value of x. (A) 16 (B) 41 (C) 5 (D) 25 (E) 66