Ni
Express your answer in condensed form in the order of orbital filling as a string without blank space between orbitals. For example, [He]2s22p2 should be entered as [He]2s^22p^2.

Answer: D. The Government could take away research funds if ethical standards are not met

The government enforce ethical standards of scientific experiments

B. The government could take away research funds if ethical

standards are not met.

Ethical standards are a set of principles established by the founders of the organization to communicate its underlying moral values. This code provides a framework that can be used as a reference for decision making processes.

Politicians and bureaucrats control scientific research and research outcomes by selectively funding projects that look for potential disasters, ideally global disasters.

This analysis focuses on whether and how the statements in these eight codes specify core moral norms (Autonomy, Beneficence, Non-Maleficence, and Justice), core behavioral norms (Veracity, Privacy, Confidentiality, and Fidelity), and other norms that are empirically derived from the code statements.

To learn more about ethical standards, refer

https://brainly.com/question/13205036

#SPJ2

Answer:

0.031 m

HgO(s) ⇒ Hg(l) + 1/2 O₂(g)

Chemical change

Element

Explanation:

A 75 gram solid cube of mercury (II) oxide has a density of 2.4 × 10³ kg/m³.  What is the length of one side of the cube in cm?

Step 1: Convert the mass to kilograms

We will use the relationship 1 kg = 1,000 g.

[tex]75g \times \frac{1kg}{1,000g} = 0.075kg[/tex]

Step 2: Calculate the volume (V) of the cube

[tex]0.075kg \times \frac{1m^{3} }{2.4 \times 10^{3} kg} = 3.1 \times 10^{-5} m^{3}[/tex]

Step 3: Calculate the length (l) of one side of the cube

We will use the following expression.

[tex]V = l^{3} \\l = \sqrt[3]{V} = \sqrt[3]{3.1 \times 10^{-5} m^{3} }=0.031m[/tex]

The mercury (II) oxide completely dissociates and forms liquid mercury and oxygen gas. Write a balanced chemical equation and indicate if this process is a chemical or physical change?

The balanced chemical equation is:

HgO(s) ⇒ Hg(l) + 1/2 O₂(g)

This is a chemical change because new substances are formed.

The oxygen gas escapes and now you are left with liquid grey substance. Is this grey substance a compound, element, homogeneous mixture or heterogeneous mixture?

The liquid gray substance is Hg(l), which is an element because it is formed by just one kind of atoms.

Complete Question

The complete question is shown on the first uploaded image

Answer:

For reaction 1

    [tex]K_{eq} = 10^{29}[/tex]

     The equilibrium position is to the right

For reaction 2

        The equilibrium position is to the left

Explanation:

Generally  [tex]pKa[/tex] is mathematically evaluated as  

[tex]pKa = pKa _ \ {left }} - pKa _ \ {right }}[/tex]

And equilibrium position [tex]K_a[/tex] is mathematically evaluated as [tex]K_{eq} = 10^\ {-pK_a}[/tex]

From the question we are told that

For reaction 1

         [tex]pKa_\ {left}} \ = 9[/tex]

        [tex]pKa_\ {right }} \ = 38[/tex]

So

       [tex]pKa = 9-38[/tex]

       [tex]pKa =-29[/tex]

So  [tex]K_{eq} = 10^{-(-29)}[/tex]

      [tex]K_a = 10^{29}[/tex]

This implies that the equilibrium position is to the right

   For reaction 2

       [tex]pKa_\ {left}} \ = 15.9[/tex]

       [tex]pKa_\ {right }} \ = 9.24[/tex]

So

       [tex]pKa = 15.9-9.24[/tex]

       [tex]pKa = 6.66[/tex]

So  [tex]K_{eq} = 10^{-(6.66)}[/tex]

      [tex]K_{eq} = 10^{-6.66}[/tex]

This implies that the equilibrium position is to the left

Answer:

[tex]0.745~M[/tex]

Explanation:

In this case, we have a dilution problem. So, we have to use the dilution equation:

[tex]C_1*V_1=C_2*V_2[/tex]

Now, we have to identify the variables:

[tex]C_1~=~14.9~M[/tex]

[tex]V_1~=~25~mL[/tex]

[tex]C_2~=~?[/tex]

[tex]V_2~=~0.5~L[/tex]

Now, we have different units for the volume, so we have to do the conversion:

[tex]0.5~L\frac{1000~mL}{1~L}=~500~mL[/tex]

Now we can plug the values into the equation:

[tex]C_2=\frac{14.9~M*25~mL}{500~mL}=0.745~M[/tex]

I hope it helps!

Answer:

Here's what I get  

Explanation:

A Lewis structure shows the valence electrons surrounding the atoms.

Your structure has two problems:

Here's one way to draw a Lewis structure.

1. Draw a trial structure

Make F and O terminal atoms and give each one an octet (Fig. 1).

2. Count the valence electrons in the trial structure

5 BP + 15 LP  = 10 + 30 = 40 electrons

3. Check the number of valence electrons available  

1 S =   1 × 6 =  6 electrons

1 O =   1 × 6 =   6

4 F  = 4 × 7 = 28                    

     TOTAL = 40 electrons

The trial structure has the correct number of electrons.

4. Determine the formal charge on each atom.

To get the formal charges, we cut the covalent bonds in half.

Each atom gets the electrons on its side of the cut.

Formal charge = valence electrons in isolated atom - electrons on bonded atom

FC = VE - BE  

(a) On S

VE = 6

BE = 5 bonding electrons = 5

FC = 6 - 5 = +1

(b) On O:

VE = 6

BE = 3 LP(six electrons) + 1 bonding electron  = 7

FC = 6 - 7 = -1

(c) On F:

VE = 6

BE = 3 lone pairs(6 electrons) + 1 bonding electron = 6 + 1 =7

FC = 7 - 7 = 0

5. Minimize the formal charges

We must rearrange the valence electrons so that S gets one more and O gets one fewer.

Move a lone pair from the O to make an S=O double bond (Fig. 2).

6. Recalculate the formal charges

(a) On S

VE = 6

BE =  (3 bonding electrons) = 6

FC = 6 - 6 = 0

(b) On O:

VE = 6

BE = 2 LP(four electrons) + 2 bonding electrons = 6  

FC = 6 - 6 = 0

Fig. 2 shows the Lewis structure in which all atoms have a formal charge of  zero.

The formal charge of the atoms can be concluded zero with the bond formation between the sulfur and oxygen atom.

The lewis structure can be defined as the dot structure of the valence bond with the bonded atoms. The formal charge can be calculated with the difference in the valence electrons and the bonding electrons.

The formal charge of an atom can be zero when the valence electrons and the bonding electrons are equal. In the structure of [tex]\rm OSF_4[/tex], the formal charge has been assigned zero with the bond formation resulting in the valence electrons and bonding electrons being equal.

The lewis structure with the central S atom has been attached.

For more information about lewis structure, refer to the link:

https://brainly.com/question/4144781

Answer:

572. 3 g of NH3

Explanation:

Equation of the reaction: 3H2 + N2 ----> 2NH3

From the equation of reaction, 3 moles of H2 reacts with 1 mole of N2 to produce 2 moles of NH3.

Since N2 is in excess in the given reaction, H2 is the limiting reactant.

Molar mass of H2 = 2 g/mol

Molar mass of NH3 = 17 g/mol

Therefore 3 * 2 g of H2 reacts to produce 2 * 17 g of NH3

6 g of H2 produces 34 g of NH3

101 g of H2 will produce (34 * 101)/6 g of NH3 = 572.3 g of NH3

Therefore, 572.3 g of NH3 are produced

Answer:

572.33g of NH3.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

N2 + 3H2 —> 2NH3

Next, we shall determine the mass of the H2 that reacted and the mass of NH3 produced from the balanced equation. This is illustrated below:

Molar Mass of H2 = 2x1 = 2g/mol

Mass of H2 from the balanced equation = 3 x 2 = 6g

Molar Mass of NH3 = 14 + (3x1) = 17g/mol

Mass of NH3 from the balanced equation = 2 x 17 = 34g.

From the balanced equation above,

6g of H2 reacted to produce 34g of NH3.

Finally, we can determine the mass of ammonia (NH3) produced by reacting 101g of H2 as follow:

From the balanced equation above,

6g of H2 reacted to produce 34g of NH3.

Therefore, 101g of H2 will react to produce = ( 101 x 34) / 6 = 572.33g of NH3.

Therefore, 572.33g of NH3 is produced from the reaction.

Answer:

$11.81

Explanation:

27 lb cost $16

27/16=$1.69 per pound

$1.69*7=$11.81 for 7 lbs

Answer:

Explanation:

it is based on le chatliers principles

the left side of reaction you have 4 moles , where as at the right hand side you have 2 moles,,,,

so when you increase the pressure the reaction will shift towards the lower moles producing reaction that is reaction move towards forward in you case.

Answer:

No, the sample needs to be insoluble or sparingly soluble at room temperature so that the maximum amount of purified crystals form at room temperature and in the ice bath.

Explanation:

For a solvent to be adequate it must completely dissolve the substance to be purified when it is hot, that is, at boiling temperature only. It should be practically insoluble when the solvent is cold or at room temperature. This must occur in this way since impurities must be removed by hot filtering or dissolved in the mother liquor.

Answer:

The correct answer is 179.94 g/mol.

Explanation:

Based on the given question, the boiling point of diethyl ether us 34.500 degree C at 1 atm pressure. The boiling point of the solution given is 35.100 degree C. The Kb of diethyl ether given is 2.02 degree C/m. The weight of the compound given is 14.94 grams, the weight of the solvent (diethyl ether) is 279.5 grams.

The molecular weight of the compound can be determined by using the formula,

deltaTb = Kb * molality

Tb-To = Kb * molality

Tb-To = Kb*wt/mol.wt*1000/w (solvent)

35.100 - 34.500 = 2.02 * 14.94 / mol. wt * 1000 g / 279.5 g

0.6 = 2.02 * 53.45/ mol.wt

mol. wt = 2.02*53.45/0.6

mol. wt = 179.94 g/mol

Hence, the molecular weight of the compound is 179.94 gram per mol.

Answer:

-1648.4 kJ/mol

Explanation:

Based on Hess's law:

ΔHr = ∑n×ΔH°f(products) - ∑n×ΔH°f(reactants)

In the reaction:

4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)

ΔHr = 2 ΔH°f {Fe₂O₃} - (4ΔH°f {Fe(s)} + 3ΔH°f{O₂(g)}

As:

ΔH°f {Fe₂O₃} = -824.2kJ/mol

ΔH°f {Fe(s)} = 0.0kJ/mol

ΔH°f{O₂(g)} = 0.0kJ/mol.

Thus,

ΔHr = 2 ₓ -824.2kJ/mol =

Answer:

-1648.4 kJ

Explanation:

The product has the only nonzero heat of formation, so it is the only value needed to calculate the enthalpy of this reaction. Normally, you would want to express the enthalpy of a reaction with respect to one mole of a chemical species, whether it is a reactant or product. However, since the balanced chemical equation contains only coefficients greater than 1, you should consider how the enthalpy relates to one mole of each substance according to the coefficients. In other words,  − 1648.4  kJ  of heat is released when 4  mol  of  Fe  reacts with 3  mol  of  O2  to produce 2  mol  of  Fe2O3 .

Answer:

66.0 atm

Explanation:

We can calculate the osmotic pressure (π) using the following expression.

[tex]\pi = i \times M \times R \times T[/tex]

where,

Step 1: Calculate i

Sodium sulfate completely dissociates according to the following equation.

Na₂SO₄ ⇒ 2 Na⁺ + SO₄²⁻

Since it produces 3 ions, i = 3.

Step 2: Calculate M

We can calculate the molarity of Na₂SO₄ using the following expression.

[tex]M = \frac{mass\ of\ solute }{molar\ mass\ of\ solute\ \times liters\ of\ solution} = \frac{65.0g}{142.04g/mol \times 0.500L} =0.915M[/tex]

Step 3: Calculate T

We will use the following expression.

K = °C + 273.15

K = 20°C + 273.15 = 293 K

Step 4: Calculate π

[tex]\pi = 3 \times 0.915M \times \frac{0.08206atm.L}{mol.K} \times 293K =66.0 atm[/tex]

Answer:

At equilibrium the rate of the forward reaction is equal to the rate of the backward reaction.

When the product of a reaction at equilibrium is increased the equilibrium will shift left or to the reactant side. As a result the excess product will get converted to reactant. This is in accordance to Le Chatelier's principle.

Le Chatelier's principle states that when a system is subjected to stress the equilibrium will shift in a direction to minimize effect of the stress.

Thus the products added to the system at equilibrium will make the equilibrium shift to the reactant side, the rate of the reverse or backward reaction will increase.

Explanation:

Hope This Helps Amigo!

Answer:

sodium chloride can be used as salt

extraction sodium metal by electrolysis

a common chemical in laboratory experiments

Answer:

sodium chloride can be used as preservatives,

in preserving foods.

Answer:

Na₂SO₄

Explanation:

Barium nitrate, Ba(NO₃)₂ produce precipitate with SO₄²⁻, CO₃²⁻. That means the precipitate could be obtained from Na₂SO₄ and Na₂CO₃.

Also, magnesium nitrate, Mg(NO₃)₂, produce precipitate just with CO₃²⁻. As the unknown solution produce no precipitate, the unknown compound is:

Na₂SO₄

Answer:

4.41

Explanation:

Step 1: Write the balanced equation

CO(g) + 3 H₂(g) = CH₄(g) + H₂O(g)

Step 2: Calculate the respective concentrations

[tex][CO]_i = \frac{0.500mol}{5.00L} = 0.100M[/tex]

[tex][H_2]_i = \frac{1.500mol}{5.00L} = 0.300M[/tex]

[tex][H_2O]_{eq} = \frac{0.198mol}{5.00L} = 0.0396M[/tex]

Step 3: Make an ICE chart

        CO(g) + 3 H₂(g) = CH₄(g) + H₂O(g)

I       0.100      0.300        0            0

C         -x           -3x          +x          +x

E    0.100-x    0.300-3x     x            x

Step 4: Find the value of x

Since the concentration at equilibrium of water is 0.0396 M, x = 0.0396

Step 5: Find the concentrations at equilibrium

[CO] = 0.100-x = 0.100-0.0396 = 0.060 M

[H₂] = 0.300-3x = 0.300-3(0.0396) = 0.181 M

[CH₄] = x = 0.0396 M

[H₂O] = x = 0.0396 M

Step 6: Calculate the equilibrium constant (Kc)

[tex]Kc = \frac{[CH_4] \times [H_2O] }{[CO] \times [H_2]^{3} } = \frac{0.0396 \times 0.0396 }{0.060 \times 0.181^{3} } = 4.41[/tex]

Answer:

U = -45.557kj

Explanation:

Before we can calculate the totally internal energy change in kilojoules firstly we need to calculate W

U=q + w .

We know that

w = PΔ V

where P is the pressure of

and V is the volume

then we can calculate the work

w = 35 atm * ( 8.20L - 2.21L)

W=35atm* 5.99L

W=209.65atmJ

But 1 atm = 101.325J

then ,

w = 209.65* 101.325 J = 21242.79 J

let us convert it to Kj

But we know that 1kJ = 10^3 J .

Then w = 21.243 kJ .

Then we can now calculate the internal energy as

U = 21.243- 66.8 kJ = -45.557kj

But we know that heat was released. Theeefore, the total internal energy change was -45.557kj

Answer:

[tex]m_{CaF_2}0.375gCaF_2[/tex]

Explanation:

Hello,

In this case, for the studied reaction:

[tex]2KF+Ca(HCO_3)_2\rightarrow CaF_2+2KHCO_3[/tex]

Thus, the first step is to compute the reacting moles of potassium fluoride by using its volume and molarity:

[tex]n_{KF}=0.0157L*0.612\frac{mol}{L} =9.61x10^{-3}molKF[/tex]

Then, we apply the 2:1 molar ratio between potassium fluoride and calcium fluoride to compute the produced moles of calcium fluoride:

[tex]n_{CaF_2}=9.61x10^{-3}molKF*\frac{1molCaF_2}{2molKF} =4.80x10^{-3}molCaF_2[/tex]

Finally, by using the molar mass of calcium fluoride (78.07 g/mol) we can compute its produced grams:

[tex]m_{CaF_2}=4.80x10^{-3}molCaF_2*\frac{78.07gCaF_2}{1molCaF_2} \\\\m_{CaF_2}0.375gCaF_2[/tex]

Best regards.

Answer:

pH = - log [concentration]

pH = - log (0.0043M)

pH = 2.37

Answer:

The correct answer to the question is Option E (Strongly retained analytes will give broad peaks).

Explanation:

The other options are true because:

A. Initial temp = 50 °C

   Final temp =  270 °C

Differences in temp = 270 - 50 = 220°C

Rate =  10 °C/minute.

So, at 10 °C/minute,

total of 220°C /10 °C = number of minutes required to reach the final temp.

220/10 = 22 minutes

B. A column has a minimum and maximum use temperature. Solutes that are already retained would remain stationary while temperatures are low. This would only change if there is an increase in temperature. Heat transfers more energy to the liquid which would make the solute interact with the column phase.

C. Weakly retained solutes may contain larger molecules, will separate by absorbing into the solvent early in separation making the mobile phase separates out into its components on the stationary phase.

D. Retained solute's vapor pressure is higher at higher temperatures making it possible for particle to escape more from the solute when the temperature is high than when it is low.

Answer:Precision can be defined as the. reproducibility of a measured value. Precision is how close the measured values are to each others. In contrast with accuracy, accuracy is the agreement between a measured value and an accepted value.

Explanation:

Answer:

[tex]pH=10.5[/tex]

Explanation:

Hello,

In this case, the dissociation of the given weak acid is:

[tex]HA\rightleftharpoons H^++A^-[/tex]

Therefore, the law of mass action for it turns out:

[tex]Ka=\frac{[H^+][A^-]}{[HA]}[/tex]

That in terms of the change [tex]x[/tex] due to the reaction extent is:

[tex]1x10^{-23}=\frac{x*x}{0.1-x}[/tex]

Thus, by solving with the quadratic equation or solver, we obtain:

[tex]x=31.6x10^{-12}M[/tex]

Which clearly matches with the hydrogen concentration in the solution, therefore, the pH is:

[tex]pH=-log(-31.6x10^{-12})\\pH=10.5[/tex]

Regards.

Answer:

B. Mixing a solute and a solvent

Explanation:

Hello,

In this case, solutions are defined as liquid homogeneous mixtures formed when two substances having affinity are mixed. It is important to notice that the two substances are known as solute, which is added to other substance that is the solvent. Therefore, answer is B. Mixing a solute and a solvent.

Notice that when two insoluble substances are mixed no solution is formed. Furthermore, if two solutes together or a solute and a precipitate are mixed, no liquid homogeneous solution is formed, as commonly solutes are solid, nevertheless, when liquid, one should have to act as the solvent.

Best regards.

Answer:

B. Mixing a solute and a solvent

Explanation:

ap3x

Answer:

0.032moles

Explanation:

2.10moles in 1000ml what about 15.25ml

(15.25×2.10)÷1000

0.032moles

Answer:

1.97kJ of energy are released.

Explanation:

The dissolution of LiOH in water is:

LiOH(s) → Li⁺(aq) + OH⁻(aq) ΔH = -23.6kJ

That means, when 1 mole of LiOH is dissolved, there are released (Because of the - in the enthalpy) 23.6kJ

2.0 g of LiOH (Molar mass: 23.95g/mol) are:

2.0g LiOH × (1 mol / 23.95g) =0.0835 moles of LiOH.

As 1 mole of LiOH release 23.6kJ, 0.0835moles release:

0.0835moles × (-23.6kJ / 1mole) = 1.97kJ of energy are released

Answer:

[tex]M=0.213M[/tex]

Explanation:

Hello,

In this case, for each nitrate-based salt, we compute the nitrate moles as shown below:

[tex]n_{NO_3^-}=20.00gCa(NO_3)_2*\frac{1molCa(NO_3)_2}{164.088 gCa(NO_3)_2} *\frac{2molNO_3^-}{1molCa(NO_3)_2} =0.244molNO_3^-[/tex]

[tex]n_{NO_3^-}=10.00gNaNO_3*\frac{1molNaNO_3}{84.9947 gNaNO_3} *\frac{1molNO_3^-}{1molNaNO_3} =0.118molNO_3^-[/tex]

[tex]n_{NO_3^-}=50.00gAl(NO_3)_3*\frac{1molAl(NO_3)_3}{212.996gAl(NO_3)_3} *\frac{3molNO_3^-}{1molAl(NO_3)_3} =0.704molNO_3^-[/tex]

We notice calcium nitrate has two moles of nitrate ion, sodium nitrate has one and aluminium nitrate has three. Hence we add the moles to obtain the total moles nitrate ion:

[tex]n_{NO_3^-}^{Tot}=0.244+0.118+0.704=1.066molNO_3^-[/tex]

Finally, we compute the molarity:

[tex]M=\frac{1.066molNO_3^-}{5.00L} \\\\M=0.213M[/tex]

Regards.

Answer: An element with the same number of protons, but a different number of neutrons

Explanation:

The # of protons in an atom is what determines what atom it is (hydrogen has 1 proton, helium has 2 protons, etc ...). You cannot change the number of protons in an atom without changing what element the atom is.

The number of electrons in atoms varies greatly because electrons are constantly gained, lost, and shared during chemical reactions.

An isotope is a variation of the same element (so they must have the same # of protons) that have different masses (and therefore a different number of neutrons).

The answer is the fourth choice, "An element with the same number of protons, but a different number of neutrons"

The isotopes refer to an element that consists of a similar number of protons but have a distinct no of neutrons.

It is considered to be the members of the family with respect to the elements that consist of a similar number of protons but have a distinct no of neutrons. The no of protons in the nucleus measured the atomic number of elements based on the periodic table.

Therefore, the fourth option is correct.

Learn more about isotopes here: https://brainly.com/question/22318349