How many moles of RbNO2 are present in a sample with 3.4 x 1024 particles?

Answers

Answer 1

Answer:

5.6 mol

Explanation:

n = N/NA

n: number of moles

N: number of particles

NA: Avogadro's constant

n = 3.4×10²⁴/6.02×10²³ mol^-1 = 5.6 mol


Related Questions

In the titration, 15 mL of CsOH solution is neutralized by 38.2 mL of 0.250 M HBr solution. What is the molarity of the CsOH solution?

Answers

Answer: 0.637M

10.2M

1.36M

0.0982M

Explanation: the answer is 1.36M

The molarity of the CsOH solution is 0.636 M.

What is molarity?

Molarity is the concentration of any substance in a place.

The reaction is

HBr + CsOH —> CsBr + H₂O

The formula of molarity

[tex]M = \dfrac{n}{V}[/tex]

[tex]\dfrac{0.25 \times 38.2 }{15} = 0.6366[/tex]

Thus, the molarity of the CsOH solution is 0.636 M.

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What are anti-oxidants? Why are they added to fat and oil containing food?​

Answers

Answer:

A substance that protects cells from the damage caused by free radicals (unstable molecules made by the process of oxidation during normal metabolism). Free radicals may play a part in cancer, heart disease, stroke, and other diseases of aging.

To prepare 250mL of calcium chloride solution with a molar concentration of 1.20mol/L, what mass of calcium chloride would be required?

Answers

Answer:

33.30 grams of CaCl2 will be required

Explanation:

Given,

Volume of solution, V= 250 ml

Molarity of solution, M= 1.20 mol/L

Molecular mass of CaCL2, S= 40+(35.5 X 2)= 111

We know,

Required mass, W= SVM/1000

Now,

W = (111 X 250 X 1.20)/1000

    = 33300/1000

    = 33.30

Therefore, 33.30 grams of Calcium Chloride will be required.

A 10.00 mL sample of a solution containing formic acid (a weak acid) was placed in a 25 mL volumetric flask and diluted to the mark with water. A 10.00 mL sample of the diluted formic acid solution was then titrated with 0.1322 M sodium hydroxide. The titration required 15.80 mL of sodium hydroxide to reach the equivalence point. Calculate the molarity and the percentage (by mass) formic acid in the original solution. The density of the formic acid solution was found to be 1.02 g/mL.

Answers

Answer:

Molarity: 0.522M

Percentage by mass: 2.36 (w/w) %

Explanation:

Formic acid, HCOOH reacts with NaOH as follows:

HCOOH + NaOH → NaCOOH + H₂O

To solve this question we must find the moles of NaOH added = Moles formic acid. Taken into account the dilution that was made we can find the moles -And molarity of formic acid and its percentage by mass as follows:

Moles NaOH = Moles HCOOH:

0.01580L * (0.1322mol / L) =0.002089 moles HCOOH

Moles in the original solution:

0.002089 moles HCOOH * (25mL / 10mL) = 0.005222 moles HCOOH

Molarity of the solution:

0.005222 moles HCOOH / 0.01000L =

0.522M

Mass HCOOH in 1L -Molar mass: 46.03g/mol-

0.522moles * (46.03g / mol) = 24.04g HCOOH

Mass solution:

1L = 1000mL * (1.02g / mL) = 1020g solution

Mass percent:

24.04g HCOOH / 1020g solution * 100

2.36 (w/w) %

The steps of preparing 2M solution of NaOH

Answers

Answer:

And 500 mL of 2M NaOH solution contains 80.02g NaOH=40.0 g of NaOH .

Explanation:

So, If we mix 40.0 g of NaOH with enough distilled water to make 500 mL, we will get a 2.00 M NaOH solution.

I hope this answers help you! :>

What is a metal oxide + acid

Metal oxide + acid —> __+__

Answers

Answer:

Metal oxide + acid —> salt + water

Explanation:

In the reaction below does water acts as the acid or as the base?
H2S + H20 - HS1- + H30+ *
O a. Neither, water is neutral
O b. Acid
O C. Base

Answers

Answer:

C. Base.

Explanation:

Hello there!

In this case, according to the given information, it turns out convenient for us to realize that the concept acid and base we should use here is based off the Bronsted-Lowry one, which says that an acid is a hydrogen donor. In such a way, since water accepts one H ion as it goes to H3O⁺, we infer it is C. Base and the H2S the acid.

Also, we can tell HS⁻ is the conjugate base and H3O⁺ the conjugate acid.

Regards!

Using what you know about the structures of the amino acid side chains and the mechanisms presented in this chapter, which of the following amino acid side chain may play the following roles in an enzymatic mechanism: a. participate in proton transfer, b. act as a nucleophile

Answers

Answer:

a. participate in proton transfer - His

b. acts as a nucleophile - Ser

Explanation:

Enzymes are regulated because they are proteins. They are categorize based on how they catalyze. Heat weakens and inactivates the enzymes because of non covalent interaction. His amino acid participate in proton transfer because it is able to act as an acid as well as a base while Ser amino acid can act as nucleophile.

orbital hauny dump bell shape is...
a Sorbital il p-orbital 1 ild-orbital pulf orbital​

Answers

Answer: the orbital with a hauny dump bell shape is the p- orbital.

Explanation:

An orbital can be defined as part of the nucleus of an atom that consists of an electron of maximum given energy. The shape of this part gives the shape of the orbitals. There are different types of orbitals which include:

--> s-orbitals: This is the type of orbital in which the probability of finding electron is the same in all directions usually at a given distance form the nucleus. Therefore the s-orbitals are SPHERICAL in shape about the nucleus and are non- directional.

--> d-orbitals: This is said to have a clover shape. This is because the electron is pushed out four times during the rotation when an opposite spin proton aligns gluons with three spin-aligned protons.

--> p-orbitals: This is said to have a DUMP-BELL shape. This is because there are three similar p-orbitals which are arranged mutually at right angles to each other along x,y, and z axes. All the three p-orbitals are of the same energy level.

help please
A gas in a sealed container has a pressure of 125 kPa at a temperature of 303K. If the temperature in the container is increased to 487K, what is the new pressure?

A 201kpa
B 200kpa
C 400kpa
D 78kpa​

Answers

Answer:

A. 201 kPa

Explanation:

We can solve this problem by using Boyle's law, which states:

P₁T₂ = P₂T₁

Where subscript 1 stands for the initial Pressure and Temperature, while 2 stands for the final conditions. That means that in this case:

P₁ = 125 kPaT₂ = 487 KP₂ = ?T₁ = 303 K

We input the data:

125 kPa * 487 K = P₂ * 303 K

And solve for P₂:

P₂ = 201 kPa

Hypothetical element A has three stable isotopes. The first isotope has a mass of 35.01 amu and an abundance of 35.00%. The second isotope has a mass of 36.01 amu and an abundance of 15.00%. The third isotope has a mass of 37.02 amu and an abundance of 50.00%. What is the atomic mass of element A

Answers

Answer:

36.16 amu

Explanation:

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

1st Isotope:

Mass of 1st isotope = 35.01 amu

Abundance of 1st isotope = 35%

2nd isotope:

Mass of 2nd isotope = 36.01 amu

Abundance of 2nd isotope = 15%

3rd isotope:

Mass of 3rd isotope = 37.02 amu

Abundance of 3rd isotope = 50%

Atomic mass of element A =?

The atomic mass of element A can be obtained as follow:

Atomic mass = [(mass of 1st × Abundance)/100] + [(mass of 2nd × Abundance)/100] + [(mass of 3rd × Abundance)/100]

= [(35.01 × 35)/100] + [(36.01 × 15)/100] + [(37.02 × 50)/100]

= 12.25 + 5.40 + 18.51

= 36.16 amu

Thus, the atomic mass of element A is 36.16 amu

Air movement and weather conditions are influenced by
A The Moon
B. Altitude
C. Thermal Energy

Answers

Answer:

The moon

Explanation:

The answer is A; Sorry i put the wrong answer by accident. I was trying to get to another question.

Give the answer below brainliest!!!

A. The moon influences the air movement

What is the mole ratio of O2 to NH3?

Answers

2:1
The ratio is 2:1. We assume you are converting between grams NH3 and mole. This also means that in order for 10 moles of NH3 to be produced, 5 moles of N2 need to react i mean state symbols for the equation: 2Mg + O2 = 2MgO .

How many moles are in 150g of Li2O?​

Answers

Answer:

moles= w/mm

moles=150/30

moles=5

I
Gggggggggggggsgstststsysgtetwtwtst

Answers

Answer:

ummm u ok?

Explanation:

Which of the following statements about the pH of 0.010 M HClO4 is correct?


pH=2.00, because [H+]=1.0×10−2M.

A: p H equals 2.00 , because the molar concentration of H with a positive 1 charge equals 1.0 times 10 to the negative 2 power molar .


pH=2.00, because [H+]=2.0×10−2M.

B: p H equals 2.00 , because the molar concentration of H with a positive 1 charge equals 1.0 times 10 to the negative 2 power molar .


pH>2.00, because HClO4 is a strong acid.

C: p H is greater than 2.00 , because H C l O 4 is a strong acid.


pH<2.00, because HClO4 is a weak acid.

Answers

Answer:

Option B: p H equals 2.00 , because the molar concentration of H with a positive 1 charge equals 1.0 times 10 to the negative 2 power molar .

pH = 2 because [H⁺] = 1×10¯² M

Explanation:

To know which option is correct, we shall determine the pH of the 0.010 M HClO₄ solution. This can be obtained as follow:

We'll begin by calculating the concentration of the hydrogen ion [H⁺] in the solution. This is illustrated below:

HClO₄ is a strong acid and will dessociates as follow:

HClO₄ (aq) —> H⁺ (aq) + ClO₄¯ (aq)

From the balanced equation above,

1 mole of HClO₄ produced 1 mole H⁺.

Therefore, 0.010 M HClO₄ will also produce 0.010 M H⁺.

Finally we shall determine the pH of the solution. This can be obtained as follow:

Concentration of the hydrogen ion [H⁺] = 0.010 = 1×10¯² M

pH =?

pH = –Log [H⁺]

pH = –Log 1×10¯²

pH = 2

Thus,

The pH = 2

because,

[H⁺] = 1×10¯² M

Thus, option B gives the correct answer to the question.

Based on the definition of pH, pH of 0.010 M solution of HClO4 equals 2.00, because the molar concentration of H with a positive 1 charge equals 1.0 times 10 to the negative 2 power molar.

What is pH?

The pH of a solution is the negative logarithm of the hydrogen ion concentration of a solution.

pH of a solution is a measure of the acidity of the solution.

pH = - log[H+]

where

[H+] is hydrogen ion concentration

For the 0.010 M solution of HClO4, [H+} = 0.01 M

pH = -log(0.01)

pH = 2.00

Therefore,  pH of 0.010 M solution of HClO4 equals 2.00, because the molar concentration of H with a positive 1 charge equals 1.0 times 10 to the negative 2 power molar.

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Evaluate each of the statements below. Select those that accurately describe the role of genes and chromosomes in
the process of inheriting a specific trait. Choose ALL that apply.
-0)
A)
Chromosomes are made of DNA.
B)
There are 26 pairs of chromosomes in humans.
C)
Alleles are the different forms of a gene that can exist.
D)
Chromosomes contain genes that control the inheritance of traits.
E)
Genes are made of chromosomes and contain all of the genetic information
for an organism.

Answers

Answer:

HEY CAN YOU POST YOUR LAST QUESTION AGAIN? CAUSE I HAVE THE ANSWER

When the pressure and number of particles of a gas are constant, which of the following is also constant

Answers

The temperature is also constant

How many grams of the bromide salt of the conjugate acid must be combined with how many grams of the weak base, to produce 1.00 L of a buffer that is

Answers

Answer:

79.1g of weak base must be combined with 56.0g of conjugate acid

Explanation:

that is 1.00 M in the weak base?

The weak base is C5H5N with a pKa of 5.17 (Ka=6.7×10-6)and a desire pH of 5.63

The equilibrium of the weak base is with the bromide salt of the conjugate acid is:

C5H5N(aq) + H2O(l) + Br- ⇄ C5H5NHBr(aq) + OH-(aq)

Where Kb = Kw / Ka = 1x10⁻¹⁴ / 6.7x10⁻⁶

Kb = 1.49x10⁻⁹ is defined as:

Kb = 1.49x10⁻⁹ = [C5H5NHBr] [OH-] / [C5H5N]

Where [OH-] = 10^-(14- pH) = 10^-(14- 5.63) = 4.255x10⁻⁹M

[C5H5N] = 1.00M

Replacing:

1.49x10⁻⁹ = [C5H5NHBr] [OH-] / [C5H5N]

1.49x10⁻⁹ = [C5H5NHBr] [4.255x10⁻⁹M] / [1.00M]

[C5H5NHBr] = 0.35M

In 1L the moles of C5H5NHBr are 0.35 moles

Mass C5H5NHBr: 160.0118g/mol

0.35 moles * (160.0118g / mol) =

56.0g of C5H5NHBr are necessaries

The mass of C5H5N is -79.1g/mol-:

1.00moles * (79.1g/mol) =

79.1g of C5H5N are necessaries

True or False
Low temperatures lead to faster dissolution rates compared to high temperatures

Answers

Answer:

false

Explanation:

this is because , high temperature speeds up the the random motion of particles which leads to high dissolution

HELP HELP HELP

NH3 + NO + N2 + H2O
5. Given 8.25 x 1025molecules of ammonia, determine the number of grams of
nitrogen produced.

Answers

Answer:

4NH3+6NO+5N2+6H20

Explanation:

Write an equation for sodium chloride and sodium oxide

Answers

Answer:

Explanation:

The Chemical Equation for each one of these compounds would be the following

Sodium Chloride: NaCl  

This compound contains 1 Sodium atom and 1 Chlorine atom

Sodium Oxide: Na₂O

This compound contains 2 Sodium atoms and 1 Oxygen atom.

Write the Ksp expression for the sparingly soluble compound cobalt(II) sulfide, CoS. If either the numerator or denominator is 1, please enter 1.

Answers

Answer:

[tex]Ksp=\frac{[Co^{2+}][S^{2-}]}{1}[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out firstly necessary to  write the chemical equation for this reaction as shown below:

[tex]CoS(s)\rightleftharpoons Co^{2+}(aq)+S^{2-}(aq)[/tex]

Thus, since solids are not included in equilibrium expressions, we can set this one up as follows:

[tex]Ksp=\frac{[Co^{2+}][S^{2-}]}{1}[/tex]

Regards!

1.00 x 10-7 moles to grams

Answers

2537 Hope this helped

It is well-known that carbon dioxide, CO2, has a much greater density than air. In fact,
CO2 gas can displace air, which is why there are regulations in place that limit the
amount of dry ice allowed in elevators. In other words, do not get trapped in an
elevator, or any enclosed space, with someone who is transporting dry ice. Calculate
the pressure exerted by the CO2 gas, in atm, if the density was measured to be 1.983
g/L on a day where the temperature is 22.165 °C.

Answers

Answer: The pressure exerted by the [tex]CO_2[/tex] gas, in atm is 1.092

Explanation:

According to the ideal gas equation:'

[tex]PV=nRT[/tex]

P = Pressure of the gas = ?

V= Volume of the gas  

T= Temperature of the gas = [tex]22.165^0C=(273+22.165)K=295.165K[/tex]  (0°C = 273 K)

n= moles of gas =  [tex]\frac{\text {given mass}}{\text {Molar mass}}[/tex]

R= Value of gas constant = 0.0821 Latm/K mol

[tex]P=\frac{mRT}{MV}[/tex]       as [tex]Density=\frac{mass}{Volume}[/tex]

[tex]P=\frac{dRT}{M}[/tex]    where d is density

[tex]P=\frac{1.983g/L\times 0.0821Latm/Kmol\times 295.165K}{44g/mol}=1.092atm[/tex]

Thus  pressure exerted by the [tex]CO_2[/tex] gas, in atm is 1.092

Question 1
3 pts
TI
Which part(s) of the following ground state electron configuration holds the valence
electrons?
At
o
1s22s22p63523p4
ОЗр
03s
O2s
O 35 and 3p

Answers

Answer:

3s and 3p

Explanation:

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

Electronic configuration =>

1s² 2s²2p⁶ 3s²3p⁴

Location of valence electron =?

From the electronic configuration given above, we can see clearly that the atom has three (3) shells.

Valence electron(s) are located at the outer most shell of an atom.

The outer most shell of the atom above is 3s and 3p.

Therefore, 3s and 3p will contain the valence electron(s)

As the temperature increases from 0°C to 25°C the amount of NH3 that can be dissolved in 100 grams of water.

A) decreases by 10 grams
B) decreases by 40 grams
C) increases by 10 grams
D) increases by 40 grams​

Answers

Answer:

decreases by 10 gram

Explanation:

The picture below shows a NASA image of the Oort cloud, a sphere of objects that are thought to surround Earth's solar system at a distance of up to one light-year from the Sun.
If the Oort cloud does exist, which of the following could explain why the objects in it may have formed this spherical shape?
A
They are held in orbits by the Sun's gravitational force.

B
They are held in Earth's solar system by Neptune's magnetic field.

C
They float freely in space because the Sun's gravitational force is too weak to hold them in orbit.

D
They are held in stationary positions around Earth's solar system by other stars in space.

Answers

The gravitational pull of the Sun keeps them in their orbits. The gravitational pull of the Sun and surrounding stars combined is most likely what gives the Oort cloud its spherical shape.

What does NASA's Oort Cloud mean?

The Oort Cloud is a spherical layer of ice objects that is thought to be located between 2,000 and 100,000 astronomical units (AU) from our Sun, a star.

What makes it the Oort Cloud?

The Oort cloud, so named after the Dutch astronomer Jan Oort who first confirmed its existence, is a collection of objects with a combined mass estimated to be 10-100 times that of Earth that are less than 100 km (60 miles) across and maybe trillions in number.

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If g of chlorine gas occupies a volume of mL at a particular temperature and pressure, what volume will g of chlorine gas occupy under the same conditions

Answers

The complete question is as follows: If 1.04 g of chlorine gas occupies a volume of 872 mL at a particular temperature and pressure, what volume will 2.08 g of chlorine gas occupy under the same conditions ?

Answer: A volume of 1744 L will 2.08 g of chlorine gas occupy under the same conditions.

Explanation:

Given: [tex]Mass_1[/tex] = 1.04 g,      [tex]V_{1}[/tex] = 872 mL

[tex]Mass_2[/tex] = 2.08 g,                [tex]V_{2}[/tex] = ?

As molar mass of chlorine is 35.5 g/mol.

Number of moles is the mass of a substance divided by its molar mass.

Hence, moles of chlorine present in 1.04 g chlorine gas is calculated as follows.

[tex]Moles = \frac{mass}{molar mass}\\= \frac{1.04 g}{35.5 g/mol}\\= 0.029 mol[/tex]

Also, moles of chlorine present in 2.08 g chlorine gas is calculated as follows.

[tex]Moles = \frac{2.08 g}{35.5 g/mol}\\= 0.058 mol[/tex]

Formula used to calculate the volume occupied by 2.08 g of chlorine gas is as follows.

[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}[/tex]

Substitute the values into above formula as follows.

[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}\\\frac{872 L}{0.029 mol} = \frac{V_{2}}{0.058 mol}\\V_{2} = 1744 L[/tex]

Thus, we can conclude that a volume of 1744 L will 2.08 g of chlorine gas occupy under the same conditions.

Identify the specific element that corresponds to each of the following electron configuration 1s2, 2s2, 2p6,3s2, 3p6

Answers

Explanation:

It's argon

As argon has atomic number 18 so it's configuration is

1s2, 2s2, 2p6,3s2, 3p6

Hope it will help :)❤

The given electron configuration 1s2, 2s2, 2p6, 3s2, 3p6 corresponds to the element argon (Ar).

Each number and letter in the electron configuration corresponds to a specific electron orbital and the number of electrons present in that orbital.

In this case, the electron configuration indicates that:

The first shell (n=1) has 2 electrons in the 1s orbital.

The second shell (n=2) has 2 electrons in the 2s orbital and 6 electrons in the 2p orbital.

The third shell (n=3) has 2 electrons in the 3s orbital and 6 electrons in the 3p orbital.

By adding up the total number of electrons (2 + 2 + 6 + 2 + 6), we find that the configuration represents 18 electrons. The element that has 18 electrons is argon, which has an atomic number of 18.

Therefore, the electron configuration 1s2, 2s2, 2p6, 3s2, 3p6 corresponds to the element argon (Ar).

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