Calculate the number of moles in 15 liters of oxygen at STP.
O 0.67 mol
O 67 mol
O 360 mol
O 1.5 mol

Answers

Answer 1

Answer:

.67 mole

Explanation:

Using ideal gas law

PV = n RT

P = pressure = 1 atm at STP

T = 273.15 K   at STP

V = 15 L

R = .082057  L-atm / K-mol

Subbing in those values:

1 (15) = n  (.082057) (273.15 )      results in n = .669 moles


Related Questions

Question 6 (Essay Worth 5 points)
(03.04 MC)
What is the name of Pb(NO3)2? Explain how you determined the bond type and the steps you used to determine the naming convention for the compound.

Answers

The correct name for the compound is written as lead II trioxonitrate V.

What is the bonding?

We know that a compound is formed when atoms are bonded together. The bond that holds atoms together could be ionic, metallic or covalent. We know that in  Pb(NO3)2, there is both ionic and covalent bonding.

This is because, the kind of bond between the lead II ion and the nitrate ion is an ionic bond while the bond between the nitrogen and the oxygen atoms in the nitrate ion is  covalent bond.

Hence, the correct name for the compound is written as lead II trioxonitrate V.

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What is the charge on the potassium ion?

Select one:

a.
1 +


b.
1 -


c.
2 -


d.
2 +

Answers

Answer:

a.) 1+

Explanation:

Potassium (K) is located in the first column of the periodic table.

These elements have 1 valence electron. As such, in order to obtain a full octet (8 valence electrons), these elements are likely to lose 1 electron. When this occurs, the element gains an overall charge of 1+ because the positively-charged protons now outnumber the negatively-charged electrons by 1.

URGENT

A 10 M concentrated stock solution of NaCl is used to prepare 3 liters of diluted 1 M solution. Which of the following is true for the process used to achieve the required dilution?

The volume of stock solution used is less than 0.2 liters.
The volume of stock solution used is less than 3 liters.
The volume of the solvent used is less than 0.2 liters.
The volume of the solvent used is more than 3 liters.

Answers

Taking into account the definition of dilution, the answer is "The volume of stock solution used is less than 3 Liters."

Dilution

When it is desired to prepare a less concentrated solution from a more concentrated one, it is called dilution.

Dilution is the process of reducing the concentration of solute in solution, which is accomplished by simply adding more solvent to the solution at the same amount of solute.

In a dilution the amount of solute does not change, but as more solvent is added, the concentration of the solute decreases, as the volume (and weight) of the solution increases.

A dilution is mathematically expressed as:

Ci×Vi = Cf×Vf

where

Ci: initial concentrationVi: initial volumeCf: final concentrationVf: final volume

Volume of stock solution used

In this case, you know:

Ci= 10 MVi= ?Cf= 1 MVf= 3 L

Replacing in the definition of dilution:

10 M× Vi= 1 M× 3 L

Solving:

Vi= (1 M× 3 L)÷ 10 M

Vi= 0.3 L

In summary, to prepare 3 Liters of 1 M solution, you need 0.3 L of the 10 M concentration stock solution and dilute to 3 L. Therefore, the answer is "The volume of stock solution used is less than 3 Liters."

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How many molecules in 5.68 g of ozone (O3)

Answers

Answer:

[tex]\boxed{\sf no.\ of \ molecules = 7.13 \times 10^{22} \ molecules}[/tex]

Explanation:

Given data::

Mass in g = m = 5.68 g

Molar mass = M = (16)3 = 48 g/mol

Avogadro's number = [tex]N_A[/tex] = 6.023 × 10²³

Required:

No. of molecules = ?

Formula:

[tex]\displaystyle no.\ of \ molecules = \frac{m}{M} \times N_A[/tex]

Solution:

Put the givens in the above formula

[tex]\displaystyle no. \ of \ molecules =\frac{5.68}{48} \times 6.023 \times 10^{23}\\\\no. \ of\ molecules = 0.12 \times 6.023 \times 10^{23}\\\\no. \ of \ molecules = 0.713\times 10^{23}\\\\no.\ of \ molecules = 7.13 \times 10^{22} \ molecules\\\\\rule[225]{225}{2}[/tex]

How many moles of solute particles are present in 1 mL (exact) of aqueous 0.0040 M Ba(OH)2?

Answers

The number of mole of solute particles are present in 1 mL (exact) of aqueous 0.0040 M Ba(OH)₂ is 0.000004 mole

What is molarity?

Molarity is defined as the mole of solute per unit litre of solution. Mathematically, it can be expressed as:

Molarity = mole / Volume

With the above formula, we can determine the number of mole present in the solution. Detail below:

How to determine the mole of the solute in the solutionVolume of solution = 1 mL = 1 / 1000 = 0.001 LMolarity of solution = 0.004 MMole of solute =?

Molarity = mole / Volume

Cross multiply

Mole = Molarity × volume

Mole of solute = 0.004 × 0.001

Mole of solute = 0.000004 mole

Thus, the mole of the solute in the solution is 0.000004 mole

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Classify the following aqueous solutions as: strong acid, weak acid, neutral, weak base, or strong base.

vinegar pH 3.2


battery acid pH 0.5


shampoo pH 7.0


ammonia pH 11.1

Answers

Vinegar pH 3.2: Weak acid

Battery acid pH 0.5: Strong acid

Shampoo pH 7.0: Neutral

Ammonia pH 11.1 Strong base

what type of forces which exist in liquid hydrogen fluoride ?

Answers

Answer:

H-F is a polar covalent molecule in which dipole-dipole interactions exists

Perform the following mathematical operation and report the answer to the appropriate number of significant figures. 5.4-4.21

Answers

Answer:

1.2   ( two significant digits)

Explanation:

5.4 - 4.21        answer should only have the the number of significant digits as the number in the equation with the least number of significant digits... in this case   5.4   is only two significant digits....so the answer should only have two significant digits

5.4 - 4.21 = 1.19     round to two digits = 1.2    

Which of the following sets of elements could replace the generic "X" symbol with their own to produce a valid dot notation for the element(s)?



Select one:

a.
carbon, silicon, and germanium


b.
oxygen, sulfur, and selenium


c.
boron, aluminum, and gallium


d.
nitrogen, phosphorus and arsenic

Answers

Symbol  "X" represents Nitrogen, phosphorus, and arsenic.as they have five valence electrons in their valance shell.

What is a Lewis notation?

A Lewis form is a completely simplified illustration of the valence shell electrons in a molecule. it's miles used to expose how the electrons are organized round man or woman atoms in a molecule. Electrons are proven as dots or for bonding electrons as a line between the 2 atoms.

Lewis systems, also known as electron-dot structures or electron-dot diagrams, are diagrams that show the bonding between atoms of a molecule, and the lone pairs of electrons that can exist within the molecule.A Lewis form is based totally at the idea of the octet rule, wherein atoms percentage electrons in order that every atom has 8 electrons in its outer shell. for example, an oxygen atom has six electrons in its outer shell.

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Why do you use the same amount of water for each shape of ice?

Answers

Answer:

the water level remains the same when the ice melts

Answer:

Because then the shape that it would look would supposed to look like, would be different.

Explanation:

Please help thank you so much

Answers

The two compounds that are the correct enol tautomers of 2-butnone are the structures shown in Option B.

What is Keto Enol Tautomerism?

Isomerism is a situation in which two compounds have the same molecular formula but do not have the same structural formula. This occurs because the atoms in the molecule are arranged differently in space. One of the types of isomerism that we have is the Keto Enol Tautomerism. The Keto Enol Tautomerism occurs between the Keto and the enol forms of a compound via the movement of electrons. It is common in ketone compounds.

In this case, we can see that the compound 2-butanone can give rise to two enol compounds that have the same molecular formula as the 2-butanone.

The two compounds that are the correct enol tautomers of 2-butnone are the structures shown in Option B.

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A tire has a pressure of 1.8 atm at 20 degrees Celsius. At the end of a long trip, the tire pressure increased to 2.0 atm. What was the temperature of the air inside the tire (in degrees Celsius)?

Answers

Answer:

52.57 Celsius

Explanation:

https://brainly.com/question/9731161

Gay-Lussac's law

P1/T1 = P2/T2

pressure 1 / temperature1 = pressure2 / temperature2

temperature has to be in kelvin

20 degrees Celsius is 293.15

1.8 / 293.15 = 2.0 / temperature2

1.8 / 293.15 = 2.0 / x

293.15 * 2.0 = 586.3

586.3 divided by 1.8 =

325.722222222 kelvin which is

52.57222222200005 Celsius

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In a perfect world, reactions can never go above 100% yield. However in reality you will sometimes get above 100% yield. Why?
Group of answer choices

A. Excess water and Impurities

B. Impurities Only

C. Excess Water Only

D. You can never have above 100% yield under any circumstance.

Answers

Answer:

You can never have above 100% yield under any circumstance

To solve such this we must know the concept of chemical reaction. Therefore, the correct option is option D that is  you can never have above 100% yield under any circumstance.

What is chemical reaction?

Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.

You can never have above 100% yield under any circumstance for any chemical reactions. Option D is the correct options among all the given options.

Therefore, the correct option is option D that is  you can never have above 100% yield under any circumstance.

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An ion of a single pure element always has an oxication number of
A. magnitude equal to its atomic number
OB. 1
OC.0
OD. None of these

Answers

Answer:

C. zero 0

Explanation:

single elements will always possess an oxication number of zero

At a certain temperature the reaction
CO2(g) + H2(g) ↔ CO(g) + H2O(g) has Kc = 2.50.
If 2.00 mol of carbon dioxide and 1.5 mol of hydrogen are placed in a 5.00 L vessel and equilibrium is established, what will be the concentration of carbon monoxide?

Answers

The concentration of carbon monoxide at equilibrium is 0.209 M.

Concentration of each gas

CO2 = 2 mol/5 L = 0.4

H2 = 1.5 mol/5L = 0.3

ICE table

Create ICE table as shown below

        CO2(g)    +     H2(g) ↔       CO(g)    +     H2O(g)

I          0.4               0.3                0                  0

C        - x                 - x                 x                   x

E        0.4 - x           0.3 - x           x                   x

Kc = [CO][H₂O] / [CO₂][H₂]

2.5 = (x²)/(0.4 - x)(0.3 - x)

x² = 2.5(0.4 - x)(0.3 - x)

x² = 2.5(0.12 - 0.7x + x²)

x²  = 0.3 - 1.75x + 2.5x²

0 = 1.5x² - 1.75x + 0.3

solve the quadratic equation using formula method;

x = 0.209

Thus, the concentration of carbon monoxide at equilibrium is 0.209 M.

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Consider the following reaction at 298K.
Pb2+ (aq) + Cu (s) Pb (s) + Cu2+ (aq)

Which of the following statements are correct?

Choose all that apply.
The reaction is product-favored.
delta G^o < 0
n = 4 mol electrons
K < 1
Eo cell < 0

Answers

The true statements are;

K < 0Eocel  < 0

What is a redox reaction?

We define a redox reaction as one in which a specie is oxidized and another is reduced.

Now;

Eo cell = cell potential = -0.13 V - (+0.34 V) = -0.47 V

n =number of moles of electrons = 2 mole of electrons

K = equilibrium constant

ΔG = change in free energy

Eo cell = 0.0592/n log K

-0.47 =  0.0592/2 log K

log K =  -0.47  * 2/0.0592

K = 1.3 * 10^-16

ΔG = -nFEo cell

ΔG = -(2 * 96500 * -0.47)

ΔG = 90.7kJ

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If I(to study),I(to pass)the exams​

Answers

If I study, I will pass the exams.

Which of the following elements has the highest electronegativity?
Group of answer choices

A. Boron

B. Nitrogen

C. Oxygen

D. Carbon

Answers

Answer:

The answer is Oxygen

The oxygen has the most electronegativity.

Based on periodic trends and the data in the table above, which of the following is the most probable value for the ionic radius of K+?

Answers

Based on periodic trends, the most probable value for the ionic radius of K⁺ is 133 pm.

What are periodic trends?

Periodic trends are the observation which are seen in the chemical and physical elements found in the periodic table.

Periodic trends is based on the periodicity of elements.

Periodicity is the variation seen in the chemical and physical properties of the elements in the period table in a regular pattern, both down the groups and across the periods.

The periodic trends observed in metallic ions is that ionic radius of metallic ions increase down a group but decreases across a period.

Based on this periodic trend, the most likely size of the potassium ion, K⁺ is 133 pm.

In conclusion, the ionic radius of metallic ions increase down a group and decrease across a period.

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Question 2 of 10
What button on a scientific calculator is used to enter a number in scientific
notation?

Answers

Answer:

It's the button with the x, and a blank box above it.

Explanation:

Check the attachments, you'll see what it looks like. It will probably look different on your calculator, but the icon should be the same or similar.

If the pressure of 1.5 moles of a gas is 2 atm and the temperature is 27°C, what is the volume of the gas?
Group of answer choices

A. 9.25 L

B. 5.0 L

C. 37.0 L

D. 18.5 L

Answers

Answer:

D

Explanation:

Ideal gas law    PV = n RT     R = .082057      T   must be in Kelvin  

                                               n = moles

V = n RT / P

  = 1.5 (.082057) ( 27+ 273.15) / 2 = 18.5 liters

Which of the following happens when a reaction reaches dynamic equilibrium in a closed system? (4 points)

Group of answer choices

The concentrations of the reactants and products increase.

The concentrations of the reactants and products decrease.

The rate of the forward reaction equals the rate of the reverse reaction.

The rate of the forward reaction is slower than the rate of the reverse reaction.

Answers

The rate of the forward reaction equals the rate of the reverse reaction.

What is dynamic equilibrium?

When it comes to chemical reactions, a dynamic equilibrium is a condition in which a reversible reaction produces products and reactants at an equal rate.

Dynamic equilibrium can only be achieved in a closed system. That is, a system in which there are no external influences in form of energy, material, or pressure.

For example, consider the following reversible reaction:

[tex]A + B < --- > C + D[/tex]

If the reaction is in dynamic equilibrium, there will not be a net production of reactants and products. In other words, the rate of production of A and B will be the same as the rate of production of C and D.

This is as opposed to static equilibrium in which the production of both reactants and products stops completely after reaching equilibrium.

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In many regions of the world, humans rely on underground water supplies called aquifers for fresh water. The amount of water an aquifer can store depends in part on the porosity of the rock or sediment in which the water is stored. Porosity is a measure of the amount of liquid that can be stored in a material and is related to the amount of empty space that exists between individual rock or sediment particles. A group of civil engineers wants to determine whether the porosity of surface soil affects aquifer recharge rates-the ability of aquifers to refill with water. The engineers conduct the following study to determine the porosity of the surface soil at various locations. The results of the study will then be compared with the recharge rates of the aquifer each location supplies with water. 1. Collect one 200-milliliter (mL) sample of soil from each of three locations. 2. Place each soil sample in a beaker. 3. Add 200 mL of water to each sample and allow the water to saturate the soil. 4. Measure the amount of standing water in each beaker (amount of water the soil did not absorb). 5. Determine the amount of water in the soil sample by subtracting the amount of standing water from 200 mL. 6. Divide the amount of water in the soil sample by 200 mL and multiply by 100 to determine the percent porosity of the soil. Which change to the experimental design would improve the reliability of the engineers' measurements?

Answers

The change to the experimental design that would improve the reliability of the engineers' measurements is C. testing single samples from more than three locations

What is an experimental design?

It should be noted that experimental design is the process of carrying out research in an objective as well as a controlled fashion in order for precision to be maximized and specific conclusions can be drawn from the hypothesis statement.

Based on the information, the locations selected are only three. Also, an area must have more types of soil with variable porosity. Hence, the collection of more soil samples may provide more accurate results than collecting soil samples from only three regions.

Therefore, change to the experimental design that would improve the reliability of the engineers' measurements is the testing single samples from more than three locations.

In conclusion, the correct option is C.

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Complete question:

Which change to the experimental design would improve the reliability of the engineers' measurements?

A. using a liquid other than water to determine porosity

B. using flasks instead of beakers

C. testing single samples from more than three locations

D. testing more samples from each location

Need the answer pretttty pleaseeeeee

Answers

Answer:

B.) their electrons are assigned to the s and p orbitals only

Explanation:

Once you get to the fourth row on the periodic table, the transition metals are introduced. The transition metals are located in the d-block and their electrons fill up d orbitals. When an element in the p-block (the right side of the table) is in one of these rows, the d-block has to fill up first.

A solution of dextrose contains 25.0 g solute in 250.0 g water. How should the percentage by mass of dextrose in this solution be calculated?

Answers

Answer:

9.10% dextrose

Explanation:

To find the mass percent, you need to use the following equation:

                               mass (g) of solute
Mass Percent  =  ---------------------------------  x  100%
                              mass (g) of solution

You can plug the given values into the equation and solve to find the mass percent of dextrose. But first, you need to calculate the mass of the solution.

Mass (solute): 25.0 g

Mass (solution): 250.0 g + 25.0 g = 275 g

                                25.0 grams
Mass Percent  =  ------------------------  x  100%
                                 275 grams

Mass Percent  =  0.0909 x 100%

Mass Percent  =  9.10%

A solution of dextrose contains 25.0 g solute in 250.0 g water. 9.10% is the percentage by mass of dextrose in this solution.

                         

A component's concentration in a combination or compound can be expressed as a mass percent, also known as a weight percent. It shows how much of the total mass of the solution or mixture is made up of the solute's (component's) mass. In chemistry, mass percent is frequently employed and stated as a percentage.

Mass Percent  =     mass (g) of solute/       mass (g) of solution x  100%

Mass (solute): 25.0 g

Mass (solution): 250.0 g + 25.0 g = 275 g

Mass Percent  =25.0 grams /    275 grams x  100%

Mass Percent  =  0.0909 x 100%

Mass Percent  =  9.10%

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Why does direct titration of aspirin with NaOH have a side reaction and how to prevent it?

Answers

Direct titration of aspirin with NaOH have a side reaction simply because aspirin is a weak acid

What is direct titration?

Direct titration can simply be defined as a type of titration in which a titrant of known concentration and volume is added to a substance in order to analyze it.

As the name implies, it is called direct titration simply because the one approaches the endpoint of the experiment directly.

Furthermore, the significance of direct titration is that it is used to find the quantity of a substance within a solution with chemical reactions.

So therefore, direct titration of aspirin with NaOH have a side reaction simply because aspirin is a weak acid

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What is an expression of Boyle's law (k = constant)?
A. V/T=K
B. V = kn
C. PV = k
D. Ptotal= P₁ + P₂ + P3 + &

Answers

Answer:

C.) PV = k

Explanation:

Boyle's Law is a variation of the Ideal Gas Law when all variables, except for pressure and volume, are held constant.

Pressure is represented by "P" and volume is represented by "V". In the Ideal Gas Law, pressure and volume are inversely proportional (if one goes up, the other goes down). That being said, the equation which best represents Boyle's Law is PV = k.

2C2H2(g)+5O2(g)=4CO2(g)+2H2O(g)

How many liters of C2H2 are required to product 12.0 moles CO2, assuming the reaction is at STP?

Answers

The volume of ethyne, C₂H₂ required to produce 12 moles of CO₂ assuming the reaction is at STP is 134.4 L

Balanced equation

2C₂H₂(g) + 5O₂(g) --> 4CO₂(g) + 2H₂O(g)

From the balanced equation above,

4 moles of CO₂ were produced by 2 moles of C₂H₂

How to determine the mole of C₂H₂ needed to produce 12 moles of CO₂

From the balanced equation above,

4 moles of CO₂ were produced by 2 moles of C₂H₂

Therefore,

12 moles of CO₂ will be produce by = (12 × 2) / 4 = 6 moles of C₂H₂

How to determine the volume (in L) of C₂H₂ needed at STP

At standard temperature and pressure (STP),

1 mole of C₂H₂ = 22.4 L

Therefore,

6 moles of C₂H₂ = 6 × 22.4

6 moles of C₂H₂ = 134.4 L

Thus, we can conclude that the volume of C₂H₂ needed for the reaction at STP is 134.4 L

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How many grams of NaOH are needed to make a 250.0 mL or a 4.2 M NaOH solution?
Group of answer choices

A. 1.05 grams NaOH

B. 42,000 grams NaOH

C. 42 grams NaOH

D. 1050 grams NaOH

Answers

Answer:

C.) 42 grams NaOH

Explanation:

To find the mass of NaOH, you need to (1) find the moles (using the molarity equation) and then (2) convert moles to grams (using the molar mass).

(Step 1)

250.0 mL / 1,000 = 0.2500 L

Molarity = moles / volume (L)

4.2 M = moles / 0.2500 L

1.05 = moles

(Step 2)

Molar Mass (NaOH): 22.990 g/mol + 15.998 g/mol + 1.008 g/mol

Molar Mass (NaOH): 39.996 g/mol

1.05 moles NaOH           39.996 g
-----------------------------  x  ------------------  =  42 grams NaOH
                                           1 mole

The graph shows the amount of a gaseous product formed over time during two trials of a reaction. A different concentration of a reactant was used during each trial while other factors were kept constant.


A graph is shown with two graph lines sloping upwards. The title on the x axis is Time and the title on the y axis is Amount of Product. The graph line with a steeper slope is labeled Trial 2 and the other is labeled Trial 1.


Which of the following statements explains which trial has a higher concentration of the reactant?


Trial 1, because the final amount of product formed is higher.

Trial 1, because this reaction lasted for a longer duration than Trial 2.

Trial 2, because this reaction was initially fast and slowed down later.

Trial 2, because the amount of product formed per unit time is higher.

Answers

Trial 1 has a lower concentration of the reactant because the  because the average rate of the reaction is lower.

What is a reaction?

The term reaction has to do with the combination of reactants in order to yield products. Now we know that the reaction profile is used to show the interaction that exists between the reactants and the products.

The y-axis of the graph is for the amount while the x axis of the graph is the reaction time. The rate of reaction is the time taken for a given amount of products to appear or for a given amount of reactants to disappear.

Thus, from the graph, we can see that trial 1 has a lower concentration of the reactant because the  because the average rate of the reaction is lower.

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Answer: D, Trial 2, because the amount of product formed per unit time is higher.

Explanation:

If the concentration is higher, more reactions can occur, causing more product.

Other Questions
Which factor contributed more to the fact that jimmy carter was a one-term president: the economy or foreign policy? how do you think historians should evaluate carter's legacy? A speaker who attempts to weaken an opponent's argument by attacking the person's integrity is guilty of the ____________ fallacy. Choose the correct demonstrative word or phrase._____ camisa es tuya.EseEstaAquelEsto It is confusing that genes and proteins are given the same name, such as epas1. lets sort them out with the basics. a gene is a section of what type of molecule? There are 12 marbles in a box. 8 are purple, and 4 are green. What is the probability of picking a purple marble and then a green marble, without replacing the first marble? Which list discussed in dave crenshaws training video helps sort gathering points? What is the structure of the following statement? The new stadium was much larger than the old one, but the older one actually had more seats.A. Problem and solutionB. Compare and contrastC. DescriptionD. Sequence What command can be used to display user account ids and group ids for your currently logged in user account? Which of the following is a solution of x + 5x = -2?05 /3325+172-5 332-5 172 The break up of the supercontinent ____________________ and changes in climate due to increased weathering and carbon dioxide drawdown are likely causes of snowball earth. If a solution has a pH of 2, what is the hydroxide ion concentration?Group of answer choicesA. 1x10-12 MB. 12C. 1x10-2 MD. 2 What is the main reason that rhetorical devices contribute to a speechs lasting impact?A. They help mask the speaker's hidden agenda with fancy wording.B. They make the speech memorable.C. They provide images so people can remember what pictures the speaker painted with words.D. They entertain the reader with puns and make people laugh. 5y23y2, when y=2. X+2y=5 and 4x-12y=-20 solve using elimination and substitution How did the time traveller know that entire years were passing in the time machine What would occur if a lipid-insoluble ca2 channel antagonist was applied to cardiac contractile cells? what is 3x+4=8 please answer quick The taft-hartley act ofa legal agreement that clarifies the terms and conditions under which labor and management will operate over a period of time is a(n)? A(n) ________ constraint addresses the sequence in which project activities must occur even after considering resource constraints. The cheetah area at a zoo is designed in a triangular fashion, surrounded on all three sides by sidewalks. The property has 67 feet of frontage on one sidewalk, and 48 feet of frontage on another; these two sidewalks intersect at a 72 angle. What is the square footage of the cheetahs' habitat? Round to the nearest hundredth.