1. A 0.130 M solution of a weak base is titrated with a 0.130 M HCl solution. After the addition of 8.50 mL of the HCl solution to 25.00 mL of the weak base solution, the pH of the solution is 9.36 . Determine the pKb of the weak base.2. Calculate the pH of the resulting solution if 23.0 mL of 0.230 M HCl(aq) is added to (a) 33.0 mL of 0.230 M NaOH(aq).

Answers

Answer 1

Answer:

1. 4.93 = pKb of the weak base

2. pH = 12.61

Explanation:

1. When a weak base, B, is being titrated with HCl, the reaction occurs as follows:

B + HCl → BH⁺ + Cl⁻

That means the moles added of HCl are the moles of BH⁺ produced and moles of B are initial moles of B - Moles of HCl

Thus:

Moles B:

Initial moles:

0.0250L * (0.130mol / L) = 3.25x10⁻³ moles B

Moles HCl:

8.5x10⁻³L * (0.130mol / L) = 1.105x10⁻³ moles HCl

3.25x10⁻³ - 1.105x10⁻³ =

2.145x10⁻³ moles B

Moles BH⁺ = Moles HCl:

1.105x10⁻³ moles BH⁺

pH of the buffer made from B/BH⁺ is determined using H-H equation for weak bases:

pOH = pKb + log [BH⁺] / [B]

Where pOH is 14-pH = 14-9.36 = 4.64

pKb is pKb of the weak base, our unknown.

[BH⁺] could be taken as moles of BH⁺ =  1.105x10⁻³ moles

And [B] as moles of B = 2.145x10⁻³ moles B

Replacing:

pOH = pKb + log [BH⁺] / [B]

4.64 = pKb + log [1.105x10⁻³ moles] / [2.145x10⁻³ moles]

4.64 = pKb -0.288

4.93 = pKb of the weak base

2. When HCl and NaOH are in solution the reaction that occurs is:

HCl + NaOH → H₂O + NaCl

To find pH we need to determine, first, which reactant is in excess:

Moles HCl:

0.023L * (0.230mol / L) = 5.29x10⁻³ moles

Moles NaOH:

0.033L * (0.0230mol / L) = 7.59x10⁻³ moles

That means NaOH is in excess and after the reaction will remain:

7.59x10⁻³ moles - 5.29x10⁻³moles = 2.3x10⁻³ moles NaOH = Moles of OH⁻

In 23+33mL = 56mL = 0.056L:

2.3x10⁻³ moles OH⁻ / 0.056L = 0.0411M [OH-]

As pOH = -log [OH-]

pOH = 1.39

pH = 14 - pOH

pH = 12.61

Related Questions

What is the concentration of chloride ions in a solution that contains 0.375 g of aluminum chloride in 15.0 mL of solution?

Answers

Answer:

0.561 M

Explanation:

Step 1: Given data

Mass of aluminum chloride (m): 0.375 gMolar mass of aluminum chloride (M): 133.34 g/molVolume of the solution (V): 15.0 mL

Step 2: Calculate the molar concentration of aluminum chloride (C)

We will use the following expression.

[tex]C = \frac{m}{M \times V(L) } = \frac{0.375g}{133.34 g/mol \times 0.0150L } = 0.187M[/tex]

Step 3: Write the reaction of dissociation of aluminum chloride

AlCl₃(aq) ⇒ Al³⁺(aq) + 3 Cl⁻(aq)

Step 4: Calculate the concentration of chloride ions

The molar ratio of AlCl₃ to Cl⁻ is 1:3. The concentration of Cl⁻ is 3/1 × 0.187 M = 0.561 M

Aluminum metal reacts with hydrochloric acid according to the following equation:

2 A l left parenthesis s right parenthesis plus 6 H C l left parenthesis a q right parenthesis rightwards arrow 2 A l C l subscript 3 left parenthesis a q right parenthesis plus 3 H subscript 2 left parenthesis g right parenthesis

If 28.1 grams of aluminum reacts with 46 mL of a 1 M HCl solution, how many grams of AlCl3 will be generated? Hint: You must determine the limiting reactant

Answers

Answer:

18 g

Explanation:

Step 1: Write the balanced equation

2 Al + 6 HCl ⇒ 2 AlCl₃ + 3 H₂

Step 2: Calculate the moles of Al

The molar mass of Al is 26.98 g/mol.

28.1 g × 1 mol/26.98 g = 1.04 mol

Step 3: Calculate the moles of HCl

46 mL of 1 M HCl react.

0.046 L × 1 mol/L = 0.046 mol

Step 4: Determine the limiting reactant

The theoretical molar ratio of Al to HCl is 2:6 = 0.33:1.

The real molar ratio of Al to HCl is 1.04:0.046 = 22.6:1

According to this, the limiting reactant is HCl.

Step 5: Calculate the mass of AlCl₃ generated from 0.046 moles of HCl

The molar ratio of HCl to AlCl₃ is 6:2. The molar mass of AlCl₃ is 133.34 g/mol.

0.046 mol HCl × 6 mol HCl/2 mol AlCl₃ × 133.34 g AlCl₃/1 mol AlCl₃ = 18 g AlCl₃

Select the best answer from the choice below. When the wavelength decreases, the frequency:

Answers

Answer:

Increases

Explanation:

Frequency and wavelength of lights are inversely proportional to each other.

The wave of light having highest frequency have shortest wavelength and the light with the shortest frequency having highest wavelength.

Formula:

Speed of light = wavelength × frequency

c = λ × f

λ = c/f

This formula shows that both are inversely related to each other.

The speed of light is 3×10⁸ m/s

Frequency is taken in Hz.

It is the number of oscillations, wave of light make in one second.

Wavelength is designated as "λ" and it is the measured in meter. It is the distance between the two crust of two trough.

Calculate the maximum mass of a metal, with equivalent mass of 20 g, that should be used in an equivalent mass determination with a 100-mL eudometer tube for collection. For the purposes of calculation, assume 80 mL of hydrogen gas produced at standard conditions. (Round to 2 sig figs)

Answers

Answer:

Explanation:

In the equivalent mass measurement , one gram equivalent of metal produces 11200 mL of hydrogen gas .

11200 mL hydrogen gas is produced by 1 gram equivalent of gas at STP

11200 mL hydrogen gas is produced by 20 g  of gas at STP

80 mL hydrogen gas is produced by 20 x 80 / 11200  g  of gas at STP

= 142.85 mg .

= 140 mg . ( rounded to 2 sig figures )

how do you determine number of valence electrons an element has

Answers

Answer:the first column has one valance electron the second has 2 and so on.

The only exception is helium that has 2.

Explanation:

If 15.5 mL of 0.225 M aqueous magnesium chloride is added to 37.5 mL of 0.250 M aqueous lead(II) nitrate, then what mass of lead(II) chloride precipitates?A. 0.485 g.B. 0.971 g.C. 1.94 g.D. 3.888 g.E. 5.82 8 g.

Answers

Answer:

B. 0.971 g

Explanation:

When MgCl₂(aq) reacts with Pb(NO₃)₂(aq), PbCl₂(s) and Mg(NO₃)₂(aq) are produced:

MgCl₂(aq) + Pb(NO₃)₂(aq) →, PbCl₂(s) + Mg(NO₃)₂(aq)

Thus, we need to find imiting reactant finding moles of each reactant:

Moles MgCl₂:

15.5mL = 0.0155L * (0.225 mol / L) = 3.49x10⁻³ moles

Moles Pb(NO₃)₂:

37.5mL = 0.0375L * (0.250mol / L) = 9.38x10⁻³ moles

As the ratio of the reactants is 1:1, the moles of PbCl₂ are 3.48x10⁻³ moles.

We need to convert thes moles to mass using molar mass of PbCl₂ (278.1g/mol), thus:

3.48x10⁻³ moles * (278.1g/mol) =

0.968g of PbCl₂ are precipitate

Thus, right answer is:

B. 0.971 g

15.0 moles of gas are in a 8.00 L tank at 22.3 ∘C∘C . Calculate the difference in pressure between methane and an ideal gas under these conditions. The van der Waals constants for methane are a=2.300L2⋅atm/mol2 a=2.300L2⋅atm/mol2 and b=0.0430L/molb=0.0430L/mol.

Answers

Answer:

[tex]\Delta P=4.10atm[/tex]

Explanation:

Hello!

In this case, since the ideal gas equation is used under the assumption of no interaction between molecules and perfectly sphere-shaped molecules but the van der Waals equation actually includes those effects, we can compute each pressure as shown below, considering the temperature in kelvins (22.3+273.15=295.45K):

[tex]P^{ideal}=\frac{nRT}{V}=\frac{15.0mol*0.08206\frac{atm*L}{mol*K}*295.45K}{8.00L}=45.5atm[/tex]

Next, since the VdW equation requires the molar volume, we proceed as shown below:

[tex]v=\frac{8.00L}{15.0mol}=0.533\frac{L}{mol}[/tex]

Now, we use its definition:

[tex]P^{VdW}=\frac{RT}{v-b} -\frac{a}{v^2}[/tex]

Thus, by plugging in we obtain:

[tex]P^{VdW}=\frac{0.08206\frac{atm*L}{mol*K}*295.45K}{0.533mol/L-0.0430L/mol} -\frac{2.300L^2*atm/mol^2}{(0.533L/mol)^2}\\\\P^{VdW}=49.44atm-8.09atm\\\\P^{VdW}=41.4atm[/tex]

Thus, the pressure difference is:

[tex]\Delta P=45.5atm-41.4atm\\\\\Delta P=4.10atm[/tex]

Best regards!

Give the location in the Periodic Table of Elements that have the same number of electron shells

all columns (groups) have the same number of shells
all periods (rows) have the same number of shells
only the transition metal elements have the same number of shells
Group VIII

Answers

Explanation:

All period have the same number of shells

If you wanted to change the polarity of hydrogen bromide (HBr) by substituting the bromine with a different atom. Which atom would increase the polarity of the molecule?

Answers

Answer:

This question is incomplete as it lacks options, the options are:

A. chlorine (CI)

B. iodine (1)

C. sulfur (S)

D. hydrogen (H)

The answer is A. Chlorine

Explanation:

Polarity of a substance in chemistry is a function of electric charges in the atoms of the molecules involved. Polarity, however, can be increased or decreased in molecules depending on the charges of the atoms that form them.

Since polarity increases when an atom in the molecule has a high ability to pull electrons toward itself i.e. electronegativity, one atom that can be substituted for Bromine in the hydrogen bromide (HBr) molecule in order to increase its polarity is CHLORINE. This is because Chlorine (Cl) is more electronegative than Bromine atom, hence, will pull more electrons from hydrogen to make the HCl molecule more polar than HBr.

To increase the polarity of HBr, the bromine atom can be replaced with a hydrogen atom.

A polar molecule is one in which a dipole moment exists. There is a positive end and a negative end in a polar molecule. Conventionally, the direction of the dipole is from the positive end of the molecule towards the negative end of the molecule.

If we want to increase the polarity of the molecule then we must substitute the bromine atom with a more electronegative atom. In this case, chlorine is  the best option.

Missing parts;

If you wanted to change the polarity of hydrogen bromide (HBr) by substituting the bromine by a different atom. Which atom would increase the polarity of the  molecule?

A. chlorine (CI)

B. iodine (1)

C. sulfur (S)

D. hydrogen (H)

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In which orbitals would the valence electrons for selenium (Se) be placed?

Answers

Answer:

Valence electrons of selenium will be placed in s and p-orbitals.

Explanation:

Hope this helps.

If the temperature of the water inside of the
pressure cooker is greater than 104'C, and the
water is still a liquid, then the pressure inside of the
pressure cooker must be
less than 1 atm
equal to 1 atm
c.
greater than 1 atm

Answers

Answer:

(C). Greater than 1atm

Explanation:

We are aware that water boils at 100 degree Celsius. Water can change its phase and become vapor at  100degree Celsius and at normal pressure which is 1atm.

In the given scenario we have enough temperature to convert water into vapor phase but we don't want it rather we want it to remain in liquid state. This can be achieved by increasing the pressure which was earlier required for vapor phase conversion. So the pressure should be greater than 1atm.

When we increase the temperature the molecules will get enough energy to escape into vapor phase, but when we will increase the pressure, it will provide hindrance to those molecules and will maintain them into Liquid state.

Ice, H2O(s), is classified as: An ionic compound, a molecular compound, a homogeneous mixture, a heterogeneous mixture

Answers

Answer:

A molecular compound.

Explanation:

An ionic compound is composed of both metal and non-metal elements. Oxygen and hydrogen are both non-metal elements.Any mixture (no matter if it is homogeneous or heterogeneous) is composed of two or more compounds.Ice is simply water in solid form, so it is only one compound. Hence the answer is A molecular compound.

Ice, H2O(s), is classified as ; ( B ) A molecular compound

Given that Ice and H₂O are the same element but in different forms therefore we can classify Ice, H₂O as been a molecular compound.

Ice and H₂O are not ionic compounds because ionic compounds are formed between metal and non-metal elements while H₂O and Ice are neither metals but are both Nonmetals

Hence we can conclude that Ice, H2O(s), is classified as A molecular compound

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Which of the following is NOT a property of gases?
Your answer:
A.They are easy to compress.
B.They expand to fill their containers.
C.They have a definite shape and a definite volume.
D.They occupy far more space than the liquids or solids from which they form.

Answers

Answer: C

Explanation:

A. As they do not have a given shape and expand to fill the container, modifying the size of the container modifies the space the gas occupies

B. They are nearly free molecules, which means no bound between them, moving fast and freely around the container

C. NOT A PROPERTY. As said before, as there are no bindings between molecules and move freely, they cannot have a fixed size cause they're always on the move.

D. Because they expand to fill the container, it's easy to them to occupy more space than in any other state, as the container is the only thing that defines how much volume they occupy

If a horse travels 20 meters in 5 seconds what is the horses speed

Answers

distance = speed * time

speed = distance / time

speed = 20 meters / 5 seconds

speed = 4 meters / second

hope this helped!

can someone put this in other words Conduct an investigation to explore the use of Punnett squares to predict genotypes and phenotypes of offspring.

Answers

To explore the use of punnett square to predict genotype and phenotypes of offsprings an investigation must be conducted

What is the work function of gold metal in kJ/mol if light with λ = 234 nm is necessary to eject electrons?

Answers

Answer

512kj/mole

Explanation:

What is the work function of gold metal in kJ/mol if light with λ = 234 nm is necessary to eject electrons?

The energy can be calculated using below expresion;

E = hc/λ

Where h= planks constant= 6.626 x 10^-34

c= speed of light= 3 x 10^

λ= wavelength

hc= (6.626 x 10^-34 x 3 x 10^ 8)

=

Which of the following statement best defines matter?

Answers

show us the statements

an ionic bond forms when atoms blank electrons

Answers

Answer:

An ionic bond forms when atoms transfer electrons.

Explanation:

Ionic bonds are formed when atoms transfer electrons. (In contrast, covalent bonds are formed when atoms share electrons.)

There's a distinction between the two: when two atoms react to form an ionic bond, one atom would completely lose one electron, while the other would completely gain that electron. The atom that loses the electron becomes a positively-charged ion called a cation, whereas the atom that gains the electron becomes a negatively-charged ion called an anion.

For example, consider the reaction between a sodium [tex]\rm Na[/tex] atom and a chlorine [tex]\rm Cl[/tex] atom: [tex]\rm Na + Cl \to NaCl[/tex].

When the sodium atom and the chlorine atom encounter, the sodium atom would lose one electron to form a positively-charged sodium ion, [tex]\rm Na^{+}[/tex]. The chlorine atom would gain that electron to form a negatively-charged chlorine ion [tex]\rm Cl^{-}[/tex].

These two ions will readily attract each other because of the opposite electrostatic charges on them. This electrostatic attraction (between two ions of opposite charges) is an ionic bond.

Overall, it would appear as if the sodium [tex]\rm Na[/tex] atom transferred an electron to the chlorine [tex]\rm Cl[/tex] atom to form an ionic bond.

In contrast, when two atoms react to form a covalent bond, they share electrons without giving any away completely. Therefore, it is possible to break certain covalent bonds apart (using a beam of laser, for example) and obtain neutral atoms.

On the other hand, when an ionic bond was broken, the result would be two charged ions- not necessarily two neutral atoms. The electron transfer could not be reversed by simply breaking the bond.

For example, when table salt [tex]\rm NaCl[/tex] is melted (at a very high temperature,) the ionic bond between the sodium ions and chloride ions would (mostly) be broken. However, doing so would only generate a mixture of [tex]\rm Na^{+}[/tex] and [tex]\rm Cl^{-}[/tex] ions- not sodium and chlorine atoms.

Answer:yea it’s transfer

Explanation:

According to the following reaction, how many grams of sulfur are formed when 37.4 g of water are formed?
2H₂S(g) + SO₂(g) → 3S(s) + 2H₂O(l)

Answers

Answer:

Mass = 100.8 g

Explanation:

Given data:

Mass of sulfur formed = ?

Mass of water formed = 37.4 g

Solution:

Chemical equation:

2H₂S + SO₂      →   3S + 2H₂O

Number of moles of water:

Number of moles = mass/molar mass

Number of moles = 37.4 g/ 18 g/mol

Number of moles = 2.1 mol

Now we will compare the moles of water and sulfur.

          H₂O         :            S

            2             :          3

           2.1            :         3/2×2.1 = 3.15

Mass of sulfur:

Mass = number of moles × molar mass

Mass = 3.15 mol × 32 g/mol

Mass = 100.8 g

The bond lengths of the X-H bonds in CH4, SiH4, and SnH4 are 1.09, 1.48, and 1.71 Å, respectively. Estimate the length of the Ge-H bond in GeH4. Which of these four hydrides has the weakest X-H bond?Estimated Ge-H bond length =________________ ÅWeakest X-H bond in ________________

Answers

Answer:

what

Explanation:what

What branch of science studies The Periodic Table? 
A.Biology
B.Earth Science
Chemistry

Atoms mover slower in the ____________. *
A.heat
B.cold

Atoms move faster in the __________. *
A.heat
B.cold

A nucleus is made of ________ and _________. *
A.protons and electrons
B.electrons and neutrons
C.protons and neutrons

Protons have what type of charge? *
A.neutral
B.negative
C.positive

Neutrons have what type of charge? *
A.neutral
B.negative
C.positive

Atoms have empty space. *
A.True
B.False

What is the center of an atom called? *
A.Neutron
B.Nitrogen
C.Nucleus

The atomic number represents the number of _______. *
A.protons
B.neutrons
C.electrons

What family of elements is most stable? *
A.metals
B.nonmetals
C.Nobel gasses

What scientist is credited with designing The Periodic Table? *
A.Albert Einstein
B.Isaac Newton
C.Dmitri Mendeleev

Atomic mass is found at the _______________.
A.top of the square
B.the middle of the square
C.the bottom of the square

The Periodic Table has elements that are liquids, gasses, and solids. *
A.True
B.False

With an atomic number of 1, which element is the lightest? *

A.Helium
B.Xenon
C.Hydrogen
D.Radon

Answers

Answers:

1. Chemistry

2. Cold

3. Heat

4. Protons and neutrons

5. Positive

6. Neutral

7. True

8. Nucleus

9. Protons

10. Nobel gasses

11. Dmitri Mendeleev

12. the bottom of the square

13. True

14. Helium

While performing a neutralization reaction, Jonna added 22.63 mL of 0.142 M H2SO4 to 46.21 mL of 0.304 M KOH. How many moles of OH- are unreacted in the solution after the neutralization is complete?

Answers

Answer:

7.623 x 10⁻³ mol OH⁻

Explanation:

The reaction that takes place is:

H₂SO₄ + 2KOH → K₂SO₄ + 2H₂O

Now we calculate how many moles of each reagent were added:

H₂SO₄ ⇒ 22.63 mL * 0.142 M = 3.213 mmol H₂SO₄KOH ⇒ 46.21 mL * 0.304 M = 14.05 mmol KOH

We calculate how many OH⁻ moles reacted with H₂SO₄:

3.213 mmol H₂SO₄ * [tex]\frac{2mmolOH^-}{1mmolH_2SO_4}[/tex] = 6.427 mmol OH⁻

Finally we substract the OH⁻ moles that reacted from the added ammount of OH⁻ moles:

14.05 mmol KOH - 6.427 mmol OH⁻ = 7.623 mmol OH⁻7.623 mmol /  1000 = 7.623 x 10⁻³ mol OH⁻

The number of moles of OH⁻ that are unreacted in the solution after the neutralization reaction is complete is 0.00770 moles OR 7.70×10⁻³ moles

First, we will write a balanced chemical equation for the neutralization reaction

The balanced chemical equation for the neutralization reaction is

H₂SO₄ + 2KOH → K₂SO₄ + 2H₂O

This means

1 mole of H₂SO₄ reacts with 2 moles of KOH to give 1 mole of K₂SO₄ and 2 moles of H₂O

To determine the number of moles of OH⁻ that are unreacted after the neutralization is complete,

We will determine the number of moles of KOH remaining in the solution after the neutralization reaction is complete

First, we will determine the number of moles of each reactant present

For H₂SO₄

Volume = 22.36 mL = 0.02236 L

Concentration = 0.142 M

From the formula,

Number of moles = Concentration × Volume

∴ Number of moles of H₂SO₄ = 0.142 × 0.02236

Number of moles of H₂SO₄ = 0.00317512 moles

For KOH

Volume = 46.21 mL = 0.04621 L

Concentration = 0.304 M

∴ Number of moles of KOH = 0.304 × 0.04621

Number of moles of KOH = 0.01404784 moles

(NOTE: This is equal to the number of moles of OH⁻ at the beginning of the reaction)

From the equation of reaction, we have that

1 mole of H₂SO₄ will neutralize 2 moles KOH

Therefore,

0.00317512 moles of H₂SO₄ will neutralize 2×0.00317512 moles KOH

2×0.00317512 = 0.00635024 moles

This means only 0.00635024 moles of KOH reacted

(NOTE: This is equal to the number of moles of OH⁻ that reacted)

Now, for the number of moles of unreacted OH⁻

Number of moles of unreacted OH⁻ = Total number of moles OH⁻ at the beginning of the reaction - Number of moles of OH⁻ that reacted

∴ Number of moles of unreacted OH⁻ = 0.01404784 moles - 0.00635024 moles

Number of moles of unreacted OH⁻ = 0.0076976 moles

Number of moles of unreacted OH⁻ ≅ 0.00770 moles OR 7.70×10⁻³ moles

Hence, the number of moles of OH⁻ that are unreacted in the solution after the neutralization is complete is 0.00770 moles OR 7.70×10⁻³ moles

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What is the atomic mass of aluminum?
Help ASAP!!!! Already got a D in that class subject is science but that’s the closed I can get

Answers

Answer:

26.982

Explanation:

Use the periodic table

plz help ❤️
Explain how the pH of water has a synergistic relationship with other substances.
Provide an example.

Answers

Answer:

Explanation:

he pH of the water will determine the toxic effects, if any, of these substances.

Pure water is neutral with the pH of 7. But when water combines with other substance the pH varies as per the acidity of the combining substance.

What is pH?

pH is the measure of acidity of a solution and mathematically it is the negative logarithm of hydrogen ion concentration. Acidic substance have a pH of less than 7 whereas, basic substance have higher pH value.

Water when combines with some acids, its acidity increases. For example acid rain resulting from the reaction of rain water with oxides of nitrogen and Sulphur forming nitric acid and sulphuric acid.

pH of water have a role in the toxic effects of components in water pH and alkalinity of water determines the coagulation of other substances in water.

Hence, the properties of other substance in water is pH dependent and might effect the alkalinity or acidity of water as well the properties of substances in water such as toxicity.

To learn more about pH , refer the link below:

https://brainly.com/question/2288405

#SPJ2

Help ASAP
Please and thank you

Answers

Answer: C

Explanation: Everything else is true.

The answer is c because it’s the only one that is not true

Which element has the lowest first ionization energy?
NEED ASAP
Select one:
a. 1s22s22p63s23p5
b. 1s22s1
c. 1s22s22p63s23p6
d. 1s22s22p63s1

Answers

Answer:

C

Explanation:

there is no explanation needed

Answer:

The value of ionization energy (IE) decreases down the group due to the increasing size as the valence electrons are more loosely bound. Thus lowest IE in this case is of Bi as it is bottom most element.

Explanation:

What type of change is sugar dissolving in water physical or chemical

Answers

Answer:

Physical

Explanation:

No new substance is formed.

The process can be reversed using evaporation to separate the sugar from the water

So the change is physical

Hope this helps :)

The mass of 900. atoms of sodium(Na)

Answers

Answer:

3.44 × 10⁻²⁰ g Na

General Formulas and Concepts:

Chemistry - Atomic Structure

Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Explanation:

Step 1: Define

900 atoms Na

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Na - 22.99 g/mol

Step 3: Convert

[tex]900 \ atoms \ Na(\frac{1 \ mol \ Na}{6.022 \cdot 10^{23} \ atoms \ Na} )(\frac{22.99 \ g \ Na}{1 \ mol \ Na} )[/tex] = 3.4359 × 10⁻²⁰ g Na

Step 4: Check

We are given 3 sig figs. Follow sig fig rules and round.

3.4359 × 10⁻²⁰ g Na ≈ 3.44 × 10⁻²⁰ g Na

Chlorophyll is found in
A. neither plant
nor animal cells.
B. animal cells.
C. plant cells.
D. plant and animal cells.

Answers

Answer:

Only plant cells

Explanation:

This organelle helps plants photosynthesize. Humans do not do that.

amu.
An atom with 4 protons, 5 neutrons, and 4 electrons has an atomic mass of
(Enter a whole number.)

Answers

Answer:

Explanation:

the sum of number of proton and neutron is known as atomic mass

so if number of proton is 4 and neutron is 5 then atomic mass of an atom is 9

Other Questions
Underground mega Monument found near Stonehenge. Which statement is a central idea of the article solve the system of equations and choose the correct ordered pair. 4x+5y=222x+3y = 12 Find the line of reflection if the image of (-5,-2) is each of the following? Choose the one below that is NOT a requirement for the fitness journal.heart ratehair colorfitness levelweight It's Your Decision- What Would You Do? Read the following scenario and address the four questions regarding what you would do in this situation: Coach Mitchells football Wildcats are down 14-12 with one minute to play. The fans scream as Robbie, the Wildcats star tailback, makes his way downfield, dodging and spinning his way to the two-yard line. As Robbie gets to his feet, he takes a cheap shot to the kidney of his tackler and spits toward the tackler. Turning around, Robbie sees Coach Mitchell staring directly at him. Both Coach Mitchell and Robbie know that this behavior goes against the coachs philosophy and team rules. The crowd is going wild in the stands as the referee signals first down; the Wildcats are only two yards away from a win and the teams first postseason game in 15 years. How would you respond if you were the coach? Who will be affected by your decision? How will your decision affect Robbie? How will your decision affect the rest of the team? What is kinetic energy? A. the energy an object has due to its motion B. the energy derived from chemical reactions C. the energy an object has due to its position D. the energy an object releases as heat Please select the best answer from the choices provided. A B C D What is the mass, in grams, of 2.3 moles of gold? QUESTION 24Calculate [H 30+] of a solution with a pH of 2.14. $39 for a case of 75 bananas alg 2 complex numbers in standard form! please help me :( Which form of government is at least characterized by having least amount of political participation Plssss helpppp ASAPPwill mark BRAINLIEST!!! south african education landscape Every year a turkey gets pardoned by thepresident of the United States. Who was the firstpresident to do this? Why would a government have to be very careful when it decides which goods should have a tariff? How do these decisions influence trade in the home country? According to the Woodlawn Park Zoo in Seattle, Washington, the average heightin inches (h) of a baby giraffe during its first week can be described by theequation h = 72 + 1.2d, where d is the number of days since it was born.Which statement explains the meaning of the 1.2 in the equation? CJ wrote several pairs of values that he thought wereequivalent. Which of his equations are correct? Pick all thatapply.1.25 = 125%0.03 = 30%0.001 = 1%60%50%22 23 66.6%Guys I need help Im gonna fail math if a football is thrown upward, its height above theground is given by the equation s=-16t^2+Vot+so, whereVo and so are the initial velocity and intial height of theFootball, respectively, and t is the time in seconds.supposethe football is thrown from the top of a building that is192 feet tall, with an initiae speed of 96 feet per second.a)write the polynomial that gives the height of the Football in termsof the variable t (time)b) what is the height of the Football after 2 seconds haveClapsed? Will the football hit the ground after 2 seconds? what layer of the Earth is made of liquid metal? John's girlfriend is constantly asking him where he's going, what he's doing, who he's doing it with. This nagging is quite aversive to Johnny. As a result, Johnny ends his relationship. This is an example of:_______a. escape conditioning b. avoidance conditioning c. positive punishment d. not enough information