Where do you put the value for how many of each atom you need?
Multiple choice
A. Below and before the symbol.
B. Above and after the symbol.
C. Below and after the symbol.
D. Above and before the symbol.

Answers

Answer 1

Answer:A

Explanation

:


Related Questions

3 useful applications of alkaline earth metals

Answers

Answer:

1 used in paint , toothpaste

2 used in fireworks and magnets

3 used to manufacture alloys

Elements with ________ atomic mass are best possible candidates for a fusion reaction. very low moderate to heavy moderate very heavy

Answers

very low

Explanation:

Nuclear fusion is a nuclear reaction wherein small nuclei are combined to form heavier nuclei. This process constantly occurs in the sun, which is mainly composed of hydrogen and helium atoms.

A Air at a temperature of 134°C and atmospheric pressure flows with a velocity of 7 m/s over


a smooth 5 m long and 1 m wide cast iron plate. Under steady-state conditions, the air-side


surface temperature of the plates is at 120°C. Under the described conditions, determine the


overall heat transfer rate through the plate.


B-If the flat plate in (A) is replaced with a cylinder with the same surface area (heat transfer


area) and the cylinder's length is the same as the width of the plate (1.0 m), what would be the


heat transfer rate for cross air flow over the outside surface of the cylinder?


C. If the flat plate in (A) is replaced with a sphere with the same surface area (heat transfer area),


what would be the heat transfer rate for cross air flow over the outside surface of the sphere?


D- Based on your results, discuss which surface configuration is more effective for heat

Answers

The answer would be d

Below the time line, list the layers from oldest to youngest

Answers

Answer:

F,E,D,C, B, A, G, H, I

Explanation:

I think. It goes bottom to top. the fault probably cause g to happen and maybe h but mattering on what caused what I am not positive

PLEASE HELP ME!! sue tomorrow:(

Answers

Answer:

If you are looking for the answer, for the question.

Earthquakes trigger tsunamis when the seismic activity causes the land along fault lines to move up or down

If you only wanted to increase the particle motion of a gas without increasing any of its other properties, which would the most correct situation?


a. Keep the gas at a constant pressure and keep the temperature constant, but increase the volume of the gas

b. Keep the gas in a fixed container at constant pressure and increase the temperature

c. Keep the gas in a fixed container at constant pressure and decrease the temperature

d. Keep the gas at a constant volume and keep the temperature constant, but decrease the pressure of the gas

Answers

Answer:

c

Explanation:

What is the pressure of a 1.0 L flask containing 0.12 g of He at 25°C? (R= 0.0821 L atm/mol K)

Answers

Answer:

The pressure of the flask is 0.73 atm.

Explanation:

To solve this question, we should use the ideal gas law: PV=nRT, where P represents the pressure (in atm in this case), V represents the volume (in L), n represents the number of moles of gas, R is the ideal gas constant, and T represents the temperature (in K).

Before we can plug our values into the equation, we must convert so that our units cancel out. First, we should convert our temperature from degrees Celsius to degrees K.

25°C + 273.15 = 298.15K

Next, we should convert the 0.12 g He to moles using the molar mass of He.

0.12 g He * (1 mole He/4.003 g He) = 0.029978 mol He

Now, we can plug in the values into the equation and solve for the pressure.

PV = nRT

P = (nRT)/V

P = (0.029978 mol He * 0.0821 L*atm/mol*K * 298.15 K)/(1.0 L)

P = 0.73 atm

Therefore, the correct answer is 0.73 atm.

Hope this helps!

8. Which property is used to determine the degree of polarity between two bonded atoms? A) density B) electronegativity C) pressure D) temperature​

Answers

Answer:

I think B) electronegativity is the correct answer.

Electronegativity is the property which is  used to determine the degree of polarity between two bonded atoms. Therefore, the correct option is option B.

What is polarity?

Polarity is the dispersion of electrical charge over the atoms linked by a chemical bond. Bonds between identical atoms, such as H2, are electrically homogeneous in the sense that both hydrogen atoms are electrically neutral, but bonds between different atoms are electrically inequivalent.

Electronegativity is the property which is  used to determine the degree of polarity between two bonded atoms. The relative electronegativities of the elements determine the polarity of a bond. Electronegativity is the ability of an element's atom to attract electrons to itself when it is part of a compound.

Therefore, the correct option is option B.

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How/ why does weather "happen," on Earth?

Answers

aused by the weight of the huge numbers of air molecules that make up the atmosphere. ... When air pressure is low, air flows together and then upward where it converges, rising, cooling, and forming clouds.

Answer:

Explanation:

The weather events happening in an area are controlled by changes in air pressure. Air pressure is caused by the weight of the huge numbers of air molecules that make up the atmosphere. ... When air pressure is low, air flows together and then upward where it converges, rising, cooling, and forming clouds.

What is the molarity of aqueous lithium bromide if 25.0 mL of LiBr reacts with 10.0 mL of 0.250 M Pb(NO 3) 2

Answers

The molarity of aqueous lithium bromide, LiBr solution is 0.2 M

We'll begin by calculating the number of mole of Pb(NO₃)₂ in the solution.

Volume = 10 mL = 10 / 1000 = 0.01 L Molarity of Pb(NO₃)₂ = 0.250 MMole of Pb(NO₃)₂ =?

Mole = Molarity x Volume

Mole of Pb(NO₃)₂ = 0.25 × 0.01

Mole of Pb(NO₃)₂ = 0.0025 mole

Next, we shall determine the mole of LiBr required to react with 0.0025 mole of Pb(NO₃)₂

Pb(NO₃)₂ + 2LiBr —> PbBr₂ + 2LiNO₃

From the balanced equation above,

1 mole of Pb(NO₃)₂ reacted with 2 mole of LiBr.

Therefore,

0.0025 mole of Pb(NO₃)₂ will react with = 2 × 0.0025 = 0.005 mole of LiBr

Finally, we shall determine the molarity of the LiBr solution

Mole = 0.005 mole Volume = 25 mL = 25 / 1000 = 0.025 L Molarity of LiBr =?

Molarity = mole / Volume

Molarity of LiBr = 0.005 / 0.025

Molarity of LiBr = 0.2 M

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In one to two sentences, describe an experiment that would show that intramolecular forces (attractions between atoms within molecules) are stronger than intermolecular forces (attractions between molecules).

Answers

Answer:

intra moleculer force is the force which you can't see

I want a pharmacist technician to help me with a question please

Answers

I can help with your question

How many liters of 0.200 M sodium hydroxide do you need to titrate 0.300 L of a 0.100 M diprotic acid to the equivalence point?

Answers

The volume of the sodium hydroxide solution needed for the reaction is 0.3 L

We'll begin by writing the balanced equation for the reaction.

H₂X + 2NaOH → 2H₂O + Na₂X

From the balanced equation above, the following data were obtained:

The mole ratio of the acid, H₂X (nA) = 1The mole ratio of base, NaOH (nB) = 2

From the question given above, the following data were obtained:

Molarity of base, NaOH (Mb) = 0.2 M. Volume of acid, H₂X (Va) = 0.3 L. Molarity of acid, H₂X (Ma) = 0.1 M. Volume of base, NaOH (Vb) =?

MaVa / MbVb = nA / nB

(0.1 × 0.3) / (0.2 × Vb) = 1/2

0.03 / (0.2 × Vb) = 1/2

Cross multiply

0.03 × 2 = 0.2 × Vb

0.06 = 0.2 × Vb

Divide both side by 0.2

Vb = 0.06 / 0.2

Vb = 0.3 L

Therefore, the volume of NaOH needed for the reaction is 0.3 L

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Anyone mind answering this

Answers

Its option A: double replacement

What are the gas laws? (Include Boyle's law, charles's law, gay lussac's law, an avogadro's law) Could someone please summarize these for me ples? Brainliest answer also yes

Answers

Answer:

Boyle's Law: When the pressure of a gas increases, the volume of the gas will decrease as long as the temperature and amount of gas are constant.

So basically pressure is inversely proportional to Volume, when one increases, the other decreases, vice versa.

Equation: [tex]P_{1} V_{1} = P_{2} V_{2}[/tex]

Charles Law: When the temperature of a gas increases, the volume of a gas will also increase if the pressure and amount of gas are constant.

So basically Temperature and volume are directly proportional.

Equation: [tex]\frac{V_{1}}{T_{1}} = \frac{V_{2} }{T_{2} }[/tex]

Gay Lussac's Law: When the temperature of a gas increases, the pressure of a gas also increases when volume and the amount of gas remain constant.

Basically, Temperature and Pressure are directly proportional.

Equation: [tex]\frac{P_{1}}{T_{1}} = \frac{P_{2} }{T_{2} }[/tex]

Avogadro's Law: The most intuitive gas law. When you increase the amount of gas, the volume will also increase.

Meaning the moles (amount of gas) is directly proportional to volume.

Equation: [tex]\frac{V_{1} }{n_{1} } = \frac{V_{2} }{n_{2} }[/tex] (n stands for moles)

There is a combined gas law and ideal gas law but those are just the gas laws mentioned above but combined together. These should be everything.

Answer:

Boyle Law is when pressure and volume have a reverse relationship when temperature is the same.Charles law is basically when volume and temperature have a relationship when the pressure is the same.Lussac Law is I think just when I pressure and temperature is directly tied together when the volume stays the same.I dont think there is any "avogadro law", there is only pressure volume and temperature.

Please give brainliest thanks :D

NO BOTS PLEASE HELP

How many moles are present in 885.46 grams of sodium bicarbonate NaHCO 3 ) ? Molar mass of sodium bicarbonate ( NaHCO 3 )=84.01 g/mol A. 6.3471 x 10^ 24 moles; 0.9877 * 10 ^ - 2 * m * o * l * e * s C. 10.540 moles D 84.007 moles

Answers

Answer:

C. 10.540 moles

Explanation:

divide grams by molar mass to get moles

What volume of 0.100 M AgNO3 is
needed to react completely with
45.0 mL of 0.230 M Na2S?
2AgNO3 + Na2S → Ag2S + 2NaNO3
[?] mL AgNO3

Answers

Answer:

448mL AgNO3

Explanation:

M x V

n = 0.230 x .045 = 0.01

2AgNO3 + Na2S --> Ag2S+2NaNO3

1 mol Ag2S --> 2 moles AgNO3

.01 mol Ag2S --> ? moles AgNO3

.01x2/1=.02 moles AgNO3

Moles to L conversion is multiplying by 22.4L so we do .02 x 22.4=0.448L

Then we convert to mL so we multiply by 1000 (1000 x 0.448)

448mL AgNO3

There you go friend, good luck with chemistry :)

What is the volume of HCl (r= 1.17 g / cm ^ 3, omega = 36 \%) required to precipitate silver in the form of AgCl from 2, 000 g of an alloy containing 22% by weight of Ag, if used 1.5 times the amount of precipitating reagent?​

Answers

The volume of precipitating reagent, HCl required to precipitate silver in the form of AgCl from 2,000 g of an alloy containing 22% by weight of Ag is 0.530 L

In order to determine the volume of precipitating reagent, HCl required to precipitate silver in the form of AgCl from 2,000 g of an alloy containing 22% by weight of Ag, the following steps are followed:

Step 1.

The concentration of the HCl solution is calculated using the formula:

Molarity = percentage * specific gravity * 1000 cm³ / molar mass * 1 L

Percentage purity of HCl = 36% = 0.36

specific gravity, r = 1.17 g/cm³

molar mass of HCl = 36.5 g/mol

Concentration of HCl = 0.36 * 1.17 * 1000 / 36.5 * 1

Concentration of HCl = 11.53 mol/L

Therefore, 1 L of HCl solution contains 11.53 moles of HCl

Step 2:

The equation of the dissociation of HCl solution is given below:

HCl (aq) ------> H⁺ (aq) + Cl⁻ (aq)

1 mole of HCl produces 1 mole of Chloride ions, Cl⁻

Equation of reaction between Silver in the alloy and HCl is given as follows:

Ag (s) + H⁺Cl⁺ (aq) -----> AgCl (s)

A white precipitate of AgCl is formed but hydrogen gas is not formed as Silver is a less reactive metal.

1 mole of HCl produces 1 mole of Cl⁻ which reacts with 1 mole of Ag to produce 1 mole of AgCl precipitate.

Step 3: Determine the mass and number of moles of silver in the alloy

Percentage of silver in the alloy = 22% = 0.22

Mass of silver in 2000 g alloy = 0.22 * 2000 g

Mass of silver in 2000 g alloy = 440 g

Number of moles of silver in 440 g of silver is determined using the formula below:

number of moles = mass / molar mass

molar mass of silver = 108 g/mol

number of moles of silver = 440 /108

number of moles of silver in the alloy = 4.074 moles

Step 4: Calculate the volume of HCl required

Since 1 mole of Cl⁻ ions react with 1 mole of Ag; 4.074 moles of Cl⁻ ions will be required to react with 4.074 moles of Ag.

1 L of HCl solution contains 11.53 moles of Cl⁻

Volume of HCl solution that contains 4.074 moles of Cl⁻ = 4.074 * 1L/11.53

Volume of HCl that contains 4.074 moles of Cl⁻ = 0.353 L

Since 1.5 times the amount of precipitating reagent HCl is required, volume of HCl required = 1.5 * 0.353 L

Volume of precipitating reagent HCl required = 0.530 L

Therefore, the volume of precipitating reagent, HCl required to precipitate silver in the form of AgCl from 2,000 g of an alloy containing 22% by weight of Ag is 0.530 L

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The frequency light of 3.52*10-7

Answers

Answer:

The speed of light, c, equals the wavelength, λ (pronounced lambda), times the frequency, ν, (pronounced noo).

c=λν

c is a constant. It is usually given as 3.00×108 m/s or 3.00×1010 cm/s rounded to three significant figures.❤

2CH3CHO+O2=> 2CH3COOH

Answers

Answer:

2CH3CHO + O2 → 2CH3COOH

Which of the following is an example of a scientific model?

The total inches of rainfall during a thunderstorm
A telescope used to study the stars
A computer program that simulates atmospheric conditions
A song about the Grand Canyon

Answers

A computer program that simulates atmosphere conditions :)

A Carnot engine takes 2000 j of heat from a reservoir at 500 k, does some work and discards some heat to a reservoir at 350k . how much work does it do, how much heat is discarded, and what is it's efficiency?​

Answers

Answer:

Explanation:

The Carnot engine is a theoretical or conceptual heat engine that has a higher efficiency than any practical or theoretical heat engine working between the same temperature range. The theoretical efficiency of a Carnot engine is considered as the highest efficiency and no practical heat engines can operate at that efficiency. A Carnot engine draws heat energy, performs useful work and the leftover energy is released from the working substance. According to the second law of thermodynamics, there must be a temperature gradient between the heat energy drawing point and release point of the heat engine.

Answer the following question attached!!

Answers

Answer:

I think It is Covalent. Not 100% sure but like 90% sure.

2. A compound with an empirical formula of C2H3Br2 has a molar mass of 373.69 g/mol. What is
the molecular formula?
(The molar mass of C2H3Br2 = 186.85 g/mol)
E) C4H6Br4
А) C2H3Br2
B) CHBr
C) C6H9Br6 D) C4H6Br2
(0.5 Points)
A

Answers

C4H6Br4
Because 373.69 is the mass we want, but the empirical mass so far is 186.85

If you notice, 186.85 x 2 is 373.69
So now we times every number in
C2H3Br2 by 2
So c4h6Br4

Empirical is the simplest whole number ratio of elements in a compound. Molecular formula is n times the empirical formula, where n is integers 1,2,... The molecular formula is  C[tex]_4[/tex]H[tex]_6[/tex]Br[tex]_4[/tex]. The correct option is option E.

What is empirical formula?

Empirical formula gives the proportion of the element that is present in a compound. It does not give information about the actual number or the arrangements of the atoms.

n=empirical formula mass÷ molecular formula mass

n=1,2,3....

empirical formula mass = 373.69 g/mol

molecular formula mass=  186.85 g/mol

substituting all the given values in the above formula, we get

n=  186.85 g/mol÷  373.69 g/mol

   = 2

Multiply C[tex]_2[/tex]H[tex]_3[/tex]Br[tex]_2[/tex] by 2, which comes out to be C[tex]_4[/tex]H[tex]_6[/tex]Br[tex]_4[/tex].

Therefore, the molecular formula is C[tex]_4[/tex]H[tex]_6[/tex]Br[tex]_4[/tex]. The correct option is option E.

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Question 13(Multiple Choice Worth 5 points)
(03.05 MC)

Liquid X has a pH of 7 and Liquid Y has a pH of 8.5. Which statement is true?

Liquid X is a base and Liquid Y is an acid.
Liquid X is an acid and Liquid Y is a base.
Liquid X is neutral and Liquid Y is a base.
Liquid X is an acid and Liquid Y is neutral.

Answers

Answer:

Liquid X is neutral and Liquid Y is a base

Explanation:

Acid: pH<7

Neutral: pH=7

Base: pH>7

For an imaginary closed economy, T = $5,000; S = $11,000; C = $48,000; and the government is running a budget surplus of $1,000. Then

Answers

Based on the information given, the private savings will be $10000 and the gross domestic product is $63000.

From the information given, he following can be gotten:

T = $5,000S = $11,000C = $48,000Budget surplus = $1000

Since, S = Y - C - G

11000 = Y - 48000 - G

Y - G = 48000 + 11000

Y - G = 59000

Budget surplus = T - G = 1000

5000 - G = 1000

G = 5000 - 1000 = 4000

The GDP will be:

Y - G = 59000

Y - 4000 = 59000

Y = 59000 + 4000 = 63000

Private savings = Y - T - C

Private savings = 63000 - 5000 - 48000

Private savings = 10000

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An unknown solution contains several chemical substances. By following a series of steps in a procedure, each of these substances can be isolated. Which of the following methods would be most appropriate for showing the steps needed to separate the substances?

A. Draw a diagram of apparatus used.
B. Create a flowchart of the various steps.
C. Build a model of the various atomic structures.
D. Construct a graph showing the times needed for each step.

Answers

Answer:

Create a flowchart of the various steps.

Explanation:

Answer:

A.

Explanation:

have a nice day^^ good morning

Which of the following statements about subatomic particles is BEST supported by information in the article?

A. The motion of large objects is just as unpredictable as that of subatomic particles.

B. Subatomic particles don’t follow the same laws of physics as large objects.

C. The force of gravity acts more strongly on subatomic particles than on large objects.

D. It is easier to measure the movement of subatomic particles than the movement of large objects.

Answers

The characteristics of the subatomic particles allow to find which is the correct answer:

B)  Subatomic particles don’t follow the same laws of physics as large objects.

Subatomic particles are the contributors to atoms, the main three being electrons, protons, and neutrons. The movement of these particles is described by the Schrodinger equation, the result of which is wave function.

To obtain the physical function of the wave mergers, the probability function must be constructed.

                        P = Ф* Ф

therefore the movement of the subatomic particulars is probabilistic at all times, when a large number of them join the mean value of this probability closer to the macroscopic movement.

Let's examine the claims.

A) False. The macroscopic motion of objects is the mean value of the microscopic motion, which with increasing size is deterministic and predictable.

B) True. Subatomic particles follow the rules of the Schrodinger equation and macroscopically Newton's second law.   Inconsequently they use different laws or to describe

C) False the most important force is electrostatic.

D) false. Large particles can be measured with a ruler, but sublimation that are orders of magnitude smaller require instruments of great pressure and complexity.

In conclusion using the characteristics of the subatomic particle we can find what the correct answer is;  

B)  Subatomic particles don’t follow the same laws of physics as large objects.

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Which type of monomer combines and forms polypeptides?
A. Nucleic acid
B. Amino acid
C. Fatty acid
D. Monosaccharide

Answers

Option A is the correct answer
The answer would be
A: Nucleic Acid
<3

Determine the volume (L) of nitrogen monoxide gas that is created at STP when 32.2 g

of solid copper reacts with excess nitric acid.

3Cu(s) + 8HNO3(aq) — 3Cu(NO3)2 (aq) + 4H2O(1) + 2NO(g)

Answers

Taking into account the reaction stoichiometry and STP conditions, the volume of nitrogen monoxide gas that is created at STP when 32.2 g of solid copper reacts with excess nitric acid is 7.5677 L.

Reaction stoichiometry

The balanced reaction is:

3 Cu(s) + 8 HNO₃(aq) → 3 Cu(NO₃)₂ (aq) + 4 H₂O(l) + 2 NO(g)

By reaction stoichiometry, the following amounts of moles of each compound participate in the reaction:

Cu: 3 molesHNO₃: 8 molesCu(NO₃)₂: 3 molesH₂O: 4 moles NO: 2 moles

The molar mass of the compounds is:

Cu: 63.54 g/moleHNO₃: 63 g/moleCu(NO₃)₂: 187.54 g/moleH₂O: 18 g/moleNO: 30 g/mole

By reaction stoichiometry, the following mass quantities of each compound participate in the reaction:

Cu: 3 moles× 63.54 g/mole= 190.62 gramsHNO₃: 8 moles× 63 g/mole= 504 gramsCu(NO₃)₂: 3 moles ×187.54 g/mole= 562.62 gramsH₂O: 4 moles ×18 g/mole= 72 gramsNO: 2 moles ×30 g/mole= 60 grams

STP conditions

The STP conditions refer to the standard temperature and pressure, which values are 0 °C and 1 atmosphere and are reference values for gases. In these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.

Moles of NO formed

The following rule of three can be applied: if by reaction stoichiometry 190.62 grams of Cu form 2 moles of NO, 32.2 grams of Cu form how many moles of NO?

moles of NO= (32.2 grams of Cu× 2 moles of NO)÷ 190.62 grams of Cu

moles of NO= 0.3378 moles

Then, 0.3378 moles of NO are formed.

Volume of NO created

Now, you can apply the following rule of three: if by definition of STP conditions 1 mole of NO occupies a volume of 22.4 liters, 0.3378 moles occupies how much volume?

volume= (0.3378 moles× 22.4 L)÷ 1 mole

volume= 7.5677 L

Finally, the volume of NO created is 7.5677 L.

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