Which statement about atoms is not correct

Answers

Answer 1

Answer:

Atoms are not able to exist independently.

Explanation:

Brainliest pls


Related Questions

A 45.0 mL solution of 0.0450 M hydroxylamine is extracted with 125 mL of solvent. The distribution constant for the reaction is 5.00 and the pKa of the protonated form of hydroxylamine is 5.960. Calculate the concentration of hydroxylamine remaining in the aqueous phase at pH=4.50 and pH=6.50 .

Answers

Answer:

pH = 4.5, concentration = 0.045 M.

pH = 6.5, concentration = 0.175 M.

Explanation:

The ka for the can be calculated by using the formula below;

Ka = 10^-pka = 10^-5.960 = 1.1 × 10^-6

The concentration of hydrogen ion at pH = 4.50 can be calculated as given below;

{H^+ } = 10^-4.50 = 3.2 × 10^-5 M.

(NB=> 10 in this regards means the inverse of log).

The next step is to determine the distribution coefficient which can be calculated by using the formula below;

distribution coefficient = (partition coefficient) × ka / ka + ( concentration of Hydrogen ion,H^+).

distribution coefficient =( 5 × 1.1 × 10^-6 ) / 1.1 × 10^-6 + 3.2 × 10^-5 M. = 5.5 × 10^-6/ 3.2 = 0.00000171875

The fraction remaining from the compound = 45.0 mL / 45.0 mL + (0.00000171875 × 125).

= 0.999995.

Thus, the concentration at pH = 4.5 = 0.999995 × 0.0450 M = 0.045 M

(B). pH=6.50, thus the concentration of Hydrogen ion = 10^-6.5 = 3.2 × 10^-7 M.

distribution coefficient = (partition coefficient) × ka / ka + ( concentration of Hydrogen ion,H^+).

distribution coefficient = (5 × 1.1 × 10^-6)/ 1.1 × 10^-6 + 3.2 × 10^-7 M).

distribution coefficient = 5.5 × 10^-6/ 1.42 × 10^-6 = 3.9.

Therefore, the concentration = 3.9 × 0.0450 M = 0.175 M.

A. 1

B. 2

C. 3

D. 4

_______________________________________________________

Answers

I think it’s B. I’m not 100% sure but I believe it is B! Srry if this is late btw.

What evidence would a scientist use to determine the age of rock in a layer?

Answers

Answer: They can find fossils and use a technology called radiocarbon to find the age of the fossil and then do an approximate about the age of the rock.

Explanation:

Calculate the final temperature (once the ice has melted) of a mixture made up initially of 70.0 mL liquid water at 28 oC and 5.0 g ice at 0.0 oC.

Answers

Answer:

21.52° C

Explanation:

From the given information:

mass of the liquid water = 70.0 mL

Initial temperature = 20°C

mass of the ice = 5.0 g

temperature of ice = 0.0°C

Using the calorimetric function:

heat lost by water = heat gained by ice.

mass of water × specific heat of water (s) × ΔT = mass of ice × specific heat of ice (s) × ΔT + n (ΔH_fusion}

⇒ 70 × 4.184 × (28 -x) = 5 × 2.108(x - 0) + [tex](\dfrac{5}{18})[/tex] × 6.01 × 10³

By solving the above equation,

x = 21.52° C

The final temperature of the mixture of water and ice is 21.5 ⁰C.

The given parameters;

initial volume of the liquid = 70 mL initial temperature of the water, = 28⁰Cmass of the ice, = 5.0 gtemperature of the ice, = 0⁰ Cspecific heat capacity of ice = 2.09 J/g ⁰Cheat of fusion of ice = 333.55 J/gspecific heat capacity of water = 4.184 J/g⁰ Cdensity of water = 1 g/ml

Let the final temperature of the mixture = t

mass of the liquid water = 1 g/ml  x 70 ml = 70 g

Apply the principle of conservation of energy to determine the final temperature of the mixture;

heat lost by water = heat gained by ice

[tex]70 \times 4.184(28 - t) = 5\times 2.09(t - 0) \ + \ 5 \times 333.55\\\\8200.64 - 292.88t = 10.45 t + 1667.75\\\\303.33t = 6532.89\\\\t = \frac{6532.89}{303.33}\\\\t = 21.5 \ ^0C[/tex]

Thus, the final temperature of the mixture of water and ice is 21.5 ⁰C.

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Which is the best example and explanation that a physical change has occurred?
fireworks exploding, because energy is released as light and heat
gasoline burning, because it forms water vapor and carbon dioxide
O crushing an ice cube, because the chemical structure of the ice cube is changed
dicing potatoes, because the molecules are separated but remain the same substance

Answers

dicing potatoes, because the molecules are separated but remain the same substance

Answer:

For the people wondering, yes, dicing potatoes is the correct answer. Because a new substance has not formed.

12oz of water initially at 75oF is mixed with 20oz of water intiially at 140oF. What is the final temperature?

Answers

Answer:

[tex]115.625^{\circ}\text{F}[/tex]

Explanation:

[tex]m_1[/tex] = First mass of water = 12 oz

[tex]m_2[/tex] = Second mass of water = 20 oz

[tex]\Delta T_1[/tex] = Temperature difference of the solution with respect to the first mass of water = [tex](T-75)^{\circ}\text{F}[/tex]

[tex]\Delta T_2[/tex] = Temperature difference of the solution with respect to the second mass of water = [tex](T-75)^{\circ}\text{F}[/tex]

c = Specific heat of water

As heat gain and loss in the system is equal we have

[tex]m_1c\Delta T_1=m_2c\Delta T_2\\\Rightarrow m_1\Delta T_1=m_2\Delta T_2\\\Rightarrow 12(T-75)=20(140-T)\\\Rightarrow 12T-900=2800-20T\\\Rightarrow 12T+20T=2800+900\\\Rightarrow 32T=3700\\\Rightarrow T=\dfrac{3700}{32}\\\Rightarrow T=115.625^{\circ}\text{F}[/tex]

The final temperature of the solution is [tex]115.625^{\circ}\text{F}[/tex].

How many seconds are in 100 years(factor label conversion)

Answers

Answer:

0.0166

Explanation:

This conversion of 100 seconds to minutes has been calculated by multiplying 100 seconds by 0.0166 and the result is 1.6666 minutes.

I hope this helps,

even a little bit

0. 0166 is how many seconds are in the year

List any three quantum numbers that describe an electron in an atom and state the relationship between any of the two

Answers

Explanation:

To completely describe an electron in an atom, four quantum numbers are needed: energy (n), angular momentum (ℓ), magnetic moment (mℓ), and spin (ms).

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Which of the following set of properties is most likely for a liquid with large, attractive intermolecular forces?

Answers

Answer:

is it ok na I hope this answers are ok

Answer:

Answer is: C) high melting point and high boiling point.

Explanation:

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What volume will be occupied by 33.0 grams of CO2 at 500 torr and 27 °C?

Answers

Answer:

V = 27.98 L

Explanation:

Given data:

Mass of CO₂ = 33.0 g

Pressure = 500 torr

Temperature = 27°C

Volume occupied = ?

Solution:

Number of moles of CO₂:

Number of moles = mass/molar mass

Number of moles = 33.0 g/ 44 g/mol

Number of moles = 0.75 mol

Volume of CO₂:

PV = nRT

R = general gas constant = 0.0821 atm.L/ mol.K  

Now we will convert the temperature.

27+273 = 300 K

Pressure = 500 /760 = 0.66 atm

By putting values,

0.66 atm×V = 0.75 mol × 0.0821 atm.L/ mol.K  × 300 K

V = 18.47 atm.L/0.66 atm

V = 27.98 L

The volume that will be occupied by 33.0 grams of CO2 at 500 torr and 27 °C is 28.11L.

IDEAL GAS LAW:

The volume of an ideal gas can be calculated using the ideal gas law equation as follows:

PV = nRT

Where;

P = pressure (atm)V = volume (L)n = number of moles (mol)R = gas law constant (0.0821 Latm/molK)T = temperature (K)

According to this question;

P = 500torr = 0.657atmV = ?n = 33/44 = 0.75molT = 27°C = 27 + 273 = 300K

0.657 × V = 0.75 × 0.0821 × 300

0.657V = 18.4725

V = 18.4725 ÷ 0.657

V = 28.11L

Therefore, the volume that will be occupied by 33.0 grams of CO2 at 500 torr and 27 °C is 28.11L.

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Write the molecular, ionic, and net ionic equations for the reaction of Sr(NO3)2(aq) and Li2SO4(aq).

Answers

Answer:

Molecular: [tex]Sr(NO_3)_2(aq) +Li_2SO_4(aq)\rightarrow SrSO_4(s)+2LiNO_3(aq)[/tex]

Ionic: [tex]Sr^{2+}(aq)+2NO_3^-(aq) +2Li^{2+}(aq)+SO_4(aq)^{2-}\rightarrow SrSO_4(s)+2Li^+(aq)+2NO_3^-(aq)[/tex]Net ionic: [tex]Sr^{2}(aq)+SO_4(aq)^{2-}\rightarrow SrSO_4(s)[/tex]

Explanation:

Hello!

In this case, since the molecular, ionic and net ionic equations show the complete molecules, ions and resulting ions respectively, for the reaction between strontium nitrate and lithium sulfate, we can notice the formation of solid strontium sulfate and lithium nitrate as shown below:

[tex]Sr(NO_3)_2(aq) +Li_2SO_4(aq)\rightarrow SrSO_4(s)+2LiNO_3(aq)[/tex]

Which is the molecular equation showing both reactants and products as molecules. Then, the ionic equation shows all the reactants and products as ions, considering that aqueous solutions dissociate whereas solid, liquid and gaseous molecules do not, therefore, we obtain:

[tex]Sr^{2+}(aq)+2NO_3^-(aq) +2Li^{2+}(aq)+SO_4(aq)^{2-}\rightarrow SrSO_4(s)+2Li^+(aq)+2NO_3^-(aq)[/tex]

Finally, for the net ionic equation, we cancel out the spectator ions, which are those at both reactants and products:

[tex]Sr^{2+}(aq)+SO_4(aq)^{2-}\rightarrow SrSO_4(s)[/tex]

Best regards!

Molecular equation - [tex]Sr(NO_3)_2(aq) +Li_2SO_4(aq) \rightarrow SrSO_4 (s) +2LiNO_3 (aq)[/tex]Ionic - [tex]Sr^{2+} (aq) +2NO_3^- (aq) +2Li^+ (aq)+ SO_4^{2-} (aq) \rightarrow SrSO_4 (s)+2Li^+ (aq) +2NO_3^- (aq)[/tex]Net ionic - [tex]Sr^{2+}(aq)+SO_4^{2-} (aq) \rightarrow SrSO_4 (s)[/tex]

A further explanation is below.

Given:

[tex]Sr(NO_3)_2 (aq)[/tex] (Strontium nitrate)[tex]L1_2SO_4 (aq)[/tex] (Lithium sulfate)

Strontium nitrate reacts with Lithium sulfate just to produce Strontium sulfate ([tex]Sr(NO_3)_2[/tex]) and Lithium nitrate ([tex]Li NO_3[/tex]).

The molecular equation will be:

→ [tex]Sr(NO_3)_2(aq) +Li_2SO_4(aq) \rightarrow SrSO_4 (s) +2LiNO_3 (aq)[/tex]

The complete ionic equation will be:

→ [tex]Sr^{2+} (aq) +2NO_3^- (aq) +2Li^+ (aq)+ SO_4^{2-} (aq) \rightarrow SrSO_4 (s)+2Li^+ (aq) +2NO_3^- (aq)[/tex]

By removing the uncharged ions from equation's will be:

Spectator ion:

→ [tex]2Li^+ (aq), 2NO_3^- (aq)[/tex]

Net ionic equation will be:

→ [tex]Sr^{2+}(aq)+SO_4^{2-} (aq) \rightarrow SrSO_4 (s)[/tex]

Thus the response above is right.

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do seeds need energy to germinate

Answers

Answer:

Seeds need oxygen so that they can produce energy for germination and growth. The embryo gets energy by breaking down its food stores. Like all organisms, this is done through a process known as aerobic respiration. —a series of reactions where energy is released from glucose, using oxygen.

Consider the following reaction:2 HgCl2(aq) + C2O42-(aq) 2 Cl-(aq) + 2 CO2(g) + Hg2Cl2(s)(a) The rate law for this reaction is first order in HgCl2(aq) and second order in C2O42-(aq). What is the rate law for this reaction?Rate = k [HgCl2(aq)] [C2O42-(aq)]Rate = k [HgCl2(aq)]2 [C2O42-(aq)]Rate = k [HgCl2(aq)] [C2O42-(aq)]2Rate = k [HgCl2(aq)]2 [C2O42-(aq)]2Rate = k [HgCl2(aq)] [C2O42-(aq)]3Rate = k [HgCl2(aq)]4 [C2O42-(aq)](b) If the rate constant for this reaction at a certain temperature is 0.0169, what is the reaction rate when [HgCl2(aq)] = 0.158 M and [C2O42-(aq)] = 0.202 M?Rate = M/s.(c) What is the reaction rate when the concentration of HgCl2(aq) is doubled, to 0.316 M while the concentration of C2O42-(aq) is 0.202 M?Rate = M/s

Answers

Answer:

b

Explanation:

The density of krypton gas at 1.35 atm and 54.1°C is ________ g/L.

a. 4.21
b. 0.304
c. 8.42
d. 0.0503
e. 0.237

Answers

a.

Explanation: I saw it on another website.

the position-time graph shows the motion of four people. label the lines on graph need on the motion description in this table.​

Answers

Line 1: straight horizontal line
Line 2: straight line at a slope
Line 3: exponential growth curve
Line 4: the topmost curve (the one that initially increases but then starts levels out)

Answer:

4,2,3,1

Explanation:

determine moles of 1.5g of sodium carbonate.

Answers

Answer:

0.014mol

Explanation:

Given parameters:

Mass of Na₂CO₃  = 1.5g

Unknown:

Number of moles  = ?

Solution:

Number of moles of a compound is mathematically expressed as;

  Number of moles  = [tex]\frac{mass}{molar mass}[/tex]  

 Molar mass of  Na₂CO₃  = 2(23) + 12 + 3(16) = 106g/mol

 Number of moles = [tex]\frac{1.5}{106}[/tex]   = 0.014mol

Sunday
Monday
What
The
Freak
Saturday

Answers

Answer
Long live Pop smoke
Explanation

4. One mole of oxygen contains 6.02 x 102 molecules. How many oxygen molecules are in

5.55 moles of oxygen gas?|

Answers

Answer:

3.34x10²⁴ molecules of oxygen

Explanation:

1 Mole of particles of any kind of gases or particles are always 6.022x10²³.

1 mole of electrons are 6.022x10²³ electrons

1 mole of any gas are 6.022x10²³ molecules

1 mole of oxygen are 6.022x10²³ molecules. Thus, 5.55 moles are:

3.34x10²⁴ molecules of oxygen

5. To keep your lunch cold at the beach, would you want a material
that minimizes heat transfer or maximizes heat transfer? Explain (keep it short please)

Answers

Answer:

Minimizes heat transfer

Explanation:

To keep my lunch from getting cold at the beach, a material the minimizes heat transfer will be the most desirable.

Such material should be modified to prevent had transfer by convection, conduction and radiation. This kind of material is desirable because heat generally flows from a place of high amount to that of low amount. Since the food will mostly have a temperature higher than the ambient one, it is expected that heat will flow away from the food to the environment. This will make the food cold. If such heat transfer is prevented, then, the food will remain hot.

A mixture of 10.0 g of Ne and 10.0 g Ar have a total pressure of 1.60 atm. What is the partial pressure of Ar

Answers

The partial pressure of Ne is 1.06 atm. The answer is a. 1.1 atm

Answer:

0.53 atm

Explanation:

First we have to obtain the number of moles of each gas.

Number of moles of Ne = 10g/20g/mol = 0.5 moles

Number of moles of Ar = 10 g/40 g/mol = 0.25 moles

Total number of moles = 0.5 moles + 0.25 moles = 0.75 moles

Partial pressure of Ar = number of moles of Ar/Total number of moles * total pressure

Partial pressure of Ar = 0.25 moles/ 0.75 moles * 1.60 atm

Partial pressure of Ar = 0.53 atm

write the chemical formula of tetraphosporus osctasulfide

Answers

Answer:

P4S8 .

the chemical formula of Tetraphosporus osctasulfide is p4S8

1+1 hahahahahhhahahaahahahahahahahahahahahahahaha why u dumb

Answers

Answer:

1+1=2 Unless this is a trick question. Then it's most likely 11.

Explanation:

1 + 1 = 2

thxs for the points realy tho thxs

Fluorine gas and water vapor react to form hydrogen fluoride gas and oxygen. What volume of oxygen would be produced by this reaction if 2.6em of were consumed? Also, be sure your answer has a unit symbol, and is rounded to the correct number of significant digits

Answers

Answer:

The reaction is 2F_2 (g) + 2H_2 O (g) rightarrow 4HF (g) + O_2 (g) 2 moles of fluorine gas (F_2) reacts with 2 moles of water vapors (H_2 O) to produce 4 moles of hy

Use Coulomb's Law to explain why and how atomic radius and IE have an inverse relationship.

Answers

Answer:

Such a relationship between atomic number and atomic radius is a direct correlation. an inverse correlation. According to Coulomb's Law, as the atomic number increases within a series of atoms, the nuclear attraction for electrons will also increase, thus pulling the electron(s) closer to the nucleus.

Explanation:

What forces cause mechanical weathering? Choose more than one
answer.

Answers

Answer:

mineral crystal growth

acid rain

carbonic acid

Answer:

Mineral crystal growth, Acid rain, Carbonic acid

The nucleus of an atom is made up of which of the following combinations of particles?

Answers

Answer:  Atoms of different elements are found to have different number    of protons, neutrons, and electrons. To distinguish one atom from another or to classify the various atoms, a number which indicates the number of protons in the nucleus of a given atom, is assigned to the atoms of each identified element. This number is known as the atomic number of the element. The atomic numbers for some of the elements which are associated with the study of semiconductors are given in the following table.

Explanation:

Element Symbol Atomic Number

Silicon Si 14

Germanium Ge 32

Arsenic As 33

Antimony Sb 51

Indium In 49

Gallium Ga 31

Boron B 5

Answer:

[tex]\boxed {\boxed {\sf Protons \ and \ neutrons}}[/tex]

Explanation:

The atom is made up of two main parts: the nucleus and the electron cloud.

The nucleus is the center and has two subatomic particles: the protons (positive charge) and the neutrons (no/neutral charge). The nucleus as a whole has a positive charge, since the neutrons don't provide a charge.

The electron cloud surrounds the nucleus and houses the negatively charged electrons in a "cloud" of energy levels.

So, the nucleus of the atom is made up of protons and neutrons.

If the concentration of a reactant is tripled (all other things remain constant), and the reaction rate increases nine times, what is the reaction order with respect to the tripled reactant? Enter your answer as a number.If the concentration of a reactant is increased 1.5 times (all other things remain constant), and the reaction rate increases 2.25 times, what is the reaction order with respect to the reactant? Enter your answer as a number.If the concentration of a reactant is tripled (all other things remain constant), and the reaction rate remains constant, what is the reaction order with respect to the tripled reactant? Enter your answer as a number.When 29.0 mL of 0.220 M KIO3 is combined with 38.0 mL of H2SO3 and 50.0 mL of water, what is the resulting concentration of KIO3?

Answers

Answer:[tex] \sqrt{ \times { - {2 { \times x3 \times \frac{?}{?} }^{2} }^{2} \times \frac{?}{?} }^{2} \times \frac{?}{?} } \\ [/tex]

The reaction order for the following conditions are:

a. two

b. two

What do you mean by reaction order?

Reaction order is the number of reactants, whose concentration affects the reaction rate.

The reaction order can be determined by adding the exponents of each reactant.

The rate equation is [tex]v^0 = k[A]^x + k[B]^y[/tex]

The first-order reaction is in which the reaction is dependent on one variable concentration.

The second-order reaction is that in which the reaction is dependent upon the concentration of two variables.

Thus, the correct options are a. two, b.two.

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Write a balanced half-reaction for the oxidation of gaseous nitric oxide (NO) to aqueous nitrous acid (HNO2) in acidic aqueous solution.

Answers

Answer:

NO + H₂O → HNO₂ + 1 e- + 1 H⁺

Step-by-step explanation:

NO ⇒ oxidation number of N = +2

HNO₂ ⇒ oxidation number of N= +3

Therefore, NO has to lose 1 electron to be oxidized to HNO₂. We write the half-reaction with 1 electron (1 e-) in the products side.

NO → HNO₂ + 1 e-

Now, we have 0 electrical charges in the reactants side, and a total of -1 electrical charge in the products side. As the reaction is in acidic aqueous solution, we have to add H⁺ ions to balance the charges. We perform the balance by adding 1 H⁺ (positive charge) to neutralize the negative charge in the side of the products:

NO → HNO₂ + 1 e- + 1 H⁺

Now, we perform the mass balance. We have:

N: 1 atom in both sides

O: 1 atom in reactants side and 2 atoms in products side

H: 0 atoms in reactants side, 2 atoms in products side.

Thus, we have to add 1 H₂O molecule to the reactants side to equal the masses:

NO + H₂O → HNO₂ + 1 e- + 1 H⁺

Finally, the oxidation half-reaction is:

NO + H₂O → HNO₂ + 1 e- + 1 H⁺

How many milliliters of 6.2 M M HCl H C l solution are needed to obtain 0.18 mol m o l of HCl H C l ?

Answers

Answer:

29 mL HCl

General Formulas and Concepts:

Chem

Molarity = moles of solute / liters of solution

Explanation:

Step 1: Define

6.2 M HCl

0.18 mol HCl

x L mol HCl

Step 2: Define conversions

1 L = 1000 mL

Step 3: Find L

6.2 M HCl = 0.18 mol HCl / x L HCl

(x L HCl)(6.2 M HCl) = 0.18 mol HCl

x L HCl = 0.18 mol HCl / 6.2 M HCl

x = 0.029032 L HCl

Step 4: Convert

[tex]0.029032 \ L \ HCl(\frac{1000 \ mL \ HCl}{1 \ L \ HCl} )[/tex] = 29.0323 mL HCl

Step 5: Check

We are given 2 sig figs. Follow sig fig rules.

29.0323 mL HCl ≈ 29 mL HCl

Answer:

29 mL HCl

Explanation:

The compound F20 has two lone pairs on the central oxygen atom. What's the structure of an F2O molecule? Is this compound polar or non-polar?
A. Trigonal planar, polar
B. Bent or angular non-polar
C. Bent or angular polar
D. Trigonal planar non-polar​

Answers

Answer:

Bent or Angular, Polar

Explanation:

I just took the test!

Answer:

C. Bent or angular polar

Explanation:

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