which of the following abbreviations is used to describe the toxic effects of chemicals? a. vocs b. tlv c. aqi d. ld50

Answers

Answer 1

The abbreviation used to describe the toxic effects of chemicals is "LD50." Option d is correct answer.

Among the given options, "LD50" is the abbreviation that specifically refers to the toxic effects of chemicals. LD50 stands for "lethal dose 50," which is a measure of the dosage of a substance required to cause death in 50% of a test population. It is commonly used in toxicology to assess the acute toxicity of a substance.

Option "A" (VOCs) stands for "volatile organic compounds" and refers to a group of chemicals that easily evaporate at room temperature, which can have various health and environmental effects.

Option "B" (TLV) stands for "threshold limit value" and represents the maximum concentration of a substance in the air that most workers can be exposed to without adverse effects.

Option "C" (AQI) stands for "air quality index" and is used to measure and communicate the quality of ambient air based on various pollutants and their potential health effects.

Therefore, the correct abbreviation used to describe the toxic effects of chemicals is "LD50."

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Related Questions

URGENT! Please help! Hi, I have to do a titration lab report using the Royal Society of Chemistry online titration lab. Please help me answer the following questions using the observation table I think?

URGENT! Please help! Hi, I have to do a titration lab report using the Royal Society of Chemistry online
URGENT! Please help! Hi, I have to do a titration lab report using the Royal Society of Chemistry online

Answers

Answer:

I'm sorry, but I cannot see the observations or the data table you mentioned in your question. However, I can still provide you with some general guidance on how to approach the calculations and answer the questions based on the given information.

4. To calculate the concentration of the NaOH solution, you need to know the mass of NaOH used and the volume of the solution. The formula to calculate concentration is:

Concentration (in mol/L) = (Mass of NaOH (in grams) / molar mass of NaOH) / Volume of solution (in L)

Make sure to convert the mass of NaOH to moles by dividing it by the molar mass of NaOH. The molar mass of NaOH is the sum of the atomic masses of sodium (Na), oxygen (O), and hydrogen (H).

5. The balanced equation for the neutralization reaction between NaOH and HCl is:

NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

(aq) represents an aqueous solution, and (l) represents a liquid.

6a. To calculate the average concentration of HCl in the sample from site B, you need to know the volumes and concentrations of the NaOH and HCl solutions used in the titration. Use the formula:

Concentration of HCl (in mol/L) = (Volume of NaOH solution (in L) * Concentration of NaOH (in mol/L)) / Volume of HCl solution (in L)

Multiply the volume of NaOH solution used by its concentration to find the amount of NaOH used. Then, divide this amount by the volume of HCl solution used to find the concentration of HCl.

6b. To determine the pH of the water at site B, you need to know the concentration of HCl from the previous calculation. The pH can be calculated using the formula:

pH = -log10[H+]

Since HCl is a strong acid, it dissociates completely into H+ ions. Therefore, the concentration of H+ ions is equal to the concentration of HCl. Take the negative logarithm (base 10) of the H+ concentration to find the pH.

To check if the water is safe, compare the calculated pH value to the range provided (pH 4.5-7.5). If the pH falls within this range, the water is considered safe for plant and animal reproduction in an aquatic environment.

6c. Use a similar calculation as in 6a to determine the average concentration of HCl in the sample from site C.

6d. Use the concentration of HCl from 6c to calculate the pH using the formula in 6b. Follow the same procedure to check if the water is safe based on the pH range.

7. To find the most current pH value for the Grand River, you can search for the latest data from reliable sources such as environmental agencies, research institutions, or government websites. Compare this pH value to the pH values obtained in the experiment to assess the difference between them.

Remember, without the specific data and observations, the calculations and comparisons provided here are only general guidelines. It's important to use the actual data from your experiment to obtain accurate results and conclusions.

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13. In Singapore, the legal limit for the concentration of alcohol (ethanol, C,H,OH) in the blood is 80 mg in 100 cm³ of blood. Complete the table by calculating the concentration of alcohol in mol dm-3 in a person at various states of intoxication. You may assume that 1 dm³ of blood contains 1 dm³ of water.​

13. In Singapore, the legal limit for the concentration of alcohol (ethanol, C,H,OH) in the blood is

Answers

The concentrations in mol/dm³ would be 0.002, 0.04, 0.007, and 0.01 respectively.

Concentration in mol/dm3

Since  1 dm³ of blood is taken as containing  1 dm³ of water, it means that the concentration levels are in mg/dm³.

Thus, we are tasked with the job of converting from mg/dm³ to mol/dm³.

Recall that: mole = mass in grams/molar mass in gram/mole

Molar mass of ethanol = 46.07 g/mol

80 mg of ethanol = 0.08 g = 0.08/46.07 = 0.002 mol

200 mg of ethanol = 0.2 g - 0.2/46.07 = 0.004 mol

300 mg = 0.3 g = 0.3/46.07 = 0.007 mol

500 mg = 0.5 g = 0.5/46.07 = 0.01 mol

Therefore, the respective concentrations in mol/dm³ would be 0.002, 0.04, 0.007, and 0.01 respectively.

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Help fast... thanks I’ll give you brainliest

Help fast... thanks Ill give you brainliest

Answers

Answer:

Graph E matches description 3 (the car is accelerating).

Explanation:

When the graph increases, the line is turned up (graph E). So when something accelerates, it is going to increase. In this case, it would increase by speed.

An aqueous mixture of hydrocyanic acid and ammonia has initialconcentration of 0.100 M HCN(aq) and 0.140 M NH3(aq). Atequilibrium, the CN(aq) concentration is 0.055 M. Calculate K forthe reaction.
HCN(aq) + NH3(aq) to CN(aq) + NH4(aq)

Answers

The equilibrium constant (K) for the reaction HCN(aq) + NH3(aq) ⇌ CN(aq) + NH4(aq) can be calculated using the given concentrations. The value of K is determined to be 0.036.

To calculate the equilibrium constant (K), we need to use the concentrations of the species at equilibrium. In this case, the given concentrations are:

[HCN] = 0.100 M

[NH3] = 0.140 M

[CN] = 0.055 M

Using the balanced chemical equation, we can write the expression for K as:

K = ([CN][NH4]) / ([HCN][NH3])

Substituting the given concentrations:

K = (0.055)([NH4]) / (0.100)(0.140)

We need to determine the concentration of NH4 at equilibrium. Since HCN and NH3 react to form CN and NH4, we can assume that the change in concentration of NH3 is equal to the change in concentration of NH4.

Change in [NH3] = Change in [NH4]

Let's assume x is the change in concentration of NH3 and NH4 at equilibrium. Therefore:

[HCN] = 0.100 - x

[NH3] = 0.140 - x

[CN] = 0.055 + x

[NH4] = x

Now we can substitute these values into the equilibrium constant expression:

K = (0.055 + x)(x) / ((0.100 - x)(0.140 - x))

Simplifying the expression and neglecting the x term in comparison to the initial concentrations:

K = (0.055)(x) / (0.100)(0.140)

Solving for x:

K = 0.036

Therefore, the equilibrium constant (K) for the given reaction is 0.036.


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Hydrated sodium tetraborate is heated
to drive off the water. You find there are
0.01312 mol Na2B4O7 and 0.1311 mol
H2O in the sample. What is the formula
of the hydrate?
A. Na2B4O7 H₂O
B. Na2B4O7 2H₂O
C. Na2B4O7-10H₂O
D. Na2B4O7-13H₂O

Hydrated sodium tetraborate is heatedto drive off the water. You find there are0.01312 mol Na2B4O7 and

Answers

Answer: C. Na2B4O7•10H2O

Explanation:


Hope this helps :)

The formula is tetrasodium borate-Na2B4O7.10H2O

Given- 0.0132 mol Na2B4O7 and 0.1311 mol H2O

Step 1

Using the molar mass of the anhydrous Na2B4O7 and its mass percentage, we can calculate the molar mass of the hydrate (if we look at it as 100% of the mass) by stoichiometry.

Molar mass of Na = (22.990 g/mol)

Molar mass of B = (10.811 g/mol)

Molar mass of O = (15.999 g/mol)

Molar mass of Na2B4O7= 2⋅22.990 g/mol +4⋅10.811 g/mol +7⋅15.999 g/mol = 201.217 g/mol

201.217g/mol : 52.8%=x g/mol : 100%

​x g/mol = 201.217 g/mol⋅100%÷52.8 %

x g/mol= 381.093 g/mol

Step 2

In 381.093 g of hydrate, we have 201.217 g of anhydrous Na2B4O7 , the rest of the mass is water.

381.093g−201.217g= 179.876 g of water

Molar mass of H = 1.008 g/mol

Molar mass of O = 15.999 g/mol

Molar mass of  H2O= 1.008 g/mol+ 15.999g/mol  = 18.015 g/mol

179.876g ÷18.015 = 9.98= 10 moles of water per mole of hydrate.

Plot the oxidation number of the following compounds:. H2SO4, H4P2O7, HCl, HNO3, NO, H2O, NaCl, F2, Cl2, Fe2(SO4)3

Answers

Answer:

where ni = no. of moles of any compound and mi = molecular mass of any ... Sulphur : (w) O.C. + HNO3 → H2SO4 + BaCl2 → (w1) BaSO4 ... 0.365 g of pure HCl gas is dissolved in 50 mL of solution. ... yield is 80% then calculate the amount of Cl2 produced. the amount of water ... Fe2O3 + 3SO3 Fe2(SO4)3

Explanation:

did that help if not please contact me in the comments.

What is the mass of 22 mL of gold, which has a density of 19.3 g/mL? Show your work or explain your steps.​

Answers

Answer:

424.6g

Explanation:

Density is a measure of a substance's mass over its volume.

d = m/v

we can rearrange this equation to solve for mass algebraically.

dv = m

We can then substitute the given values for our variables in the problem and solve for our answer.

22mL(19.3g/mL)= 424.6g

The equilibrium constant, Kc, for the reaction below is 0.10 at 25oC. Find the equilibrium concentration of chlorine gas, Cl2(g), if the equilibrium concentrations of ICl(g) and I2(g) are known to be 0.50 M and 0.40 M respectively.

2 ICl(g) → Cl2(g) + I2(g)

Answers

Answer:

The equilibrium concentration of chlorine gas, Cl₂(g), is 0.0625 M

Explanation:

Chemical equilibrium is established when there are two opposite reactions that take place simultaneously at the same speed, so that no changes are observed as time passes, despite the fact that the substances present continue to react with each other.

The mathematical expression that represents Chemical Equilibrium is known as the Law of Mass Action and is stated as: The ratio of the product of high concentrations to the stoichiometric coefficients in the reaction of products and reactants remains constant at equilibrium. For any reaction:

aA + bB ⇄ cC + dD

the equilibrium constant Kc is calculated as:

\(Kc=\frac{[C]^{c} *[D]^{d} }{[A]^{a} *[B]^{b}}\)

In this case, you have:

2 ICl(g) → Cl₂(g) + I₂(g)

So, the equilibrium constant Kc is:

\(Kc=\frac{[Cl_{2} ]*[I_{2} ]}{[ICl]^{2} }\)

Being:

Kc= 0.10[Cl₂]= ?[ICl]= 0.50 M[I₂]= 0.40 M

Replacing:

\(0.1=\frac{[Cl_{2} ]*0.40 M}{(0.50 M)^{2} }\)

Solving:

\(0.1=\frac{[Cl_{2} ]*0.40 M}{0.25 M^{2} }\)

0.1= 1.6 \(\frac{1}{M}\)* [Cl₂]

[Cl₂]= 0.1 ÷ 1.6 \(\frac{1}{M}\)

[Cl₂]= 0.0625 M

The equilibrium concentration of chlorine gas, Cl₂(g), is 0.0625 M

The equilibrium concentration of chlorine gas, if the equilibrium concentrations of ICl(g) and I₂(g) are known to be 0.50 M and 0.40 M respectively is 0.0625M.

How we calculate the equilibrium constant?

Equilibrium constant for any reaction will be define as the ratio of the concentration of products to the concentration of reactants with raise to their respective coefficients.

Given chemical reaction is:

2ICl(g) → Cl₂(g) + I₂(g)

Equilibrium constant for this reaction will be calculated as:

Kc = [Cl₂][I₂] / [ICl]², where

Kc = equilibrium constant = 0.10

[I₂] = concentration of iodine gas = 0.40 M

[ICl]² = concentration of ICl = 0.50 M = (0.50M)² = 0.25M²

[Cl₂] = concentration of chlorine gas = to find?

On putting all these values on the above equation and calculate for the value of [Cl₂] as follow:
[Cl₂] = Kc × [ICl]² / [I₂]

[Cl₂] = (0.10)(0.25) / (0.40)

[Cl₂] = 0.0625M

Hence, equilibrium concentration of chlorine gas is 0.0625M.

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what questions should I expect on the Chemistry module 4 DBA?
(When I’m finished with the DBA I’ll answer this question but right now I need help)

Answers

Decomposition processes should appear here on Chemistry previous modules DBA, When I'm done with the DBA, I'll respond to this query.

How do you define reaction?

Opposition or antagonism to a force, effect, or movement is a reactionary act, process, or occurrence. especially: a reaction to a particular treatment, circumstance, or stimulus; leaning toward a past and typically antiquated political or social system or policy.

What kinds of reactions are there?

Combination, disintegration, single-replacement, twofold, and combustion are the five fundamental types of chemical reactions. You can classify a reaction into one of these groups by looking at the reactants and products.

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Answer: I was asked to classify equations, balance equations, and define + explain the law of conservation of mass

a 250 gram sample of water at the boiling point had 35.0 kj of heat added. how many grams of water were vaporized? heat of vaporization for water is 40.6 kj/mole.

Answers

The required mass of water vaporized is 15.5 grams, from a 250 gram sample of water at the boiling point had 35.0 kj

Given: Mass of water (m) = 250 gHeat added (q) = 35.0 kJHeat of vaporization (ΔHvap) = 40.6 kJ/mole

To find:Mass of water vaporized (x) Formula:q = ΔHvap × nx = (q / ΔHvap) × nMass = moles × molar mass

We know that molar mass of water (H2O) = 18 g/molMoles of water vaporized (n) = (35.0 kJ / 40.6 kJ/mol) = 0.861 mol

Therefore,Mass of water vaporized (x) = 0.861 mol × 18 g/mol= 15.5  

Detailed Solution: According to the given statement,250g of water was taken at its boiling point and 35.0 kJ of heat was added to it, we need to find how many grams of water were vaporized. To solve this question, first, we need to know the heat of vaporization for water, which is 40.6 kJ/mole. It means to vaporize 1 mole of water, 40.6 kJ of heat is required.

Mass of water (m) = 250 g Heat added (q) = 35.0 kJHeat of vaporization (ΔHvap) = 40.6 kJ/molen = q / ΔHvapn = (35.0 kJ / 40.6 kJ/mol) = 0.861 molMoles of water vaporized (n) = 0.861 mol

Therefore, Mass of water vaporized (x) = 0.861 mol × 18 g/mol= 15.5 g Hence, the required mass of water vaporized is 15.5 grams.

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Level 3
Q1
Forces that are equal but opposite
are called
A. Net force
B. Friction
C. Centripetal force
D. Balanced forces

Answers

option D Balanced force

4. 12 miles of gas has a volume of 72. 3 L. The number of moles change to 29. 9 moles. What is the volume now?

Answers

The volume now is 182.16 L, by using gas laws.

To solve this problem, we need to use the gas laws, specifically the relationship between volume, number of moles, and gas constant. We can start by using the equation:PV = nRT where P is pressure, V is volume, n is number of moles, R is the gas constant, and T is temperature (which we can assume is constant in this problem).

Since we are given the initial volume (V1) and number of moles (n1), we can solve for the initial pressure (P1):

\(P1 = n_1RT/V_1\)
Next, we are asked to find the final volume (V2), but we only have the number of moles (n2) and the initial pressure (P1). We can use the same equation, but with the new values:
\(P_1V_1 = n_2RT\)

2:
\(V_2 = n_2RT/P1\)
Now we just need to plug in the values:
V2 = (29.9 mol)(0.08206 L·atm/mol·K)(273 K)/(\(n_1RT/V_1)\)
V2 = (29.9 mol)(0.08206 L·atm/mol·K)(273 K)/(12 miles of gas x 1609.34 m/mile x 3.78541 L/gal)
V2 = 95.4 L
Therefore, the volume of the gas at 29.9 moles is 95.4 L.
Initial volume (\(V_1\)) = 72.3 L
Initial moles (\(n_1\)) = 12 miles of gas (assuming you meant "moles" instead of "miles")
Final moles (n2) = 29.9 moles
We can set up a proportion:
\(V_1 / n_1 = V_2 / n_2\)
Now we can plug in the values and solve for \(V_2\):
72.3 L / 12 moles = \(V_2\) / 29.9 moles
Cross-multiply and solve for \(V_2\):
\(V_2\) = (72.3 L * 29.9 moles) / 12 moles
\(V_2\) ≈ 182.16 L
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A reaction between copper metal and silver nitrate should theoretically produce 41.8 g Ag, however in the lab only 32.3 g Ag is actually produced. What is the percent yield of silver in this reaction?

Answers

Answer:

For these problems, we need to compare the theoretical yield that we'd get from performing stoichiometry to the actual yield stated in the problem. % yield is the actual yield/theoretical yield x 100%  

Cu + 2 AgNO₠→ Cu(NOâ‚)â‚‚ + 2 Ag ==> each mole of copper yields two moles of silver  

12.7-g Cu x ( 1 mol Cu /63.5-g Cu) x ( 2 mol Ag / 1 mol Cu) x (108-g Ag / 1 mol Ag) = 43.2-g Ag. This is the theoretical yield. Now, since we got 38.1-g Ag our % yield is:

38.1-g/43.2-g x 100% = 88.2%

A reaction between copper metal and silver nitrate should theoretically produce 41.8 g Ag, however in the lab only 32.3 g Ag is actually produced. 12.9% is the percent yield of silver in the given reaction.

What is percent yield?

The % ratio of the theoretical yield to the actual yield is known as the percent yield. It is calculated as the theoretical yield multiply by 100% divided by the experimental yield. The percent yield equals 100% if the theoretical and actual yields are equal.

Because the real yield is frequently lower than the theoretical value, percent yield is typically lower than 100%. This may be due to incomplete or conflicting reactions or sample loss during recovery.

percent yield = (theoretical yield/experimental yield)×100

percent yield = (41.8/ 32.3)×100

                     = 12.9%

Therefore,  12.9% is the percent yield of silver in the given reaction.

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A student was given a 2.850-g sample of a mixture of potassium nitrate and potassium bromide and was asked to find the percentage of each compound in the mixture. She dissolved the sample and added a solution that contained an excess of silver nitrate, AgNO3. The silver ion precipitated all of the bromide ion in the mixture as AgBr. It was filtered, dried, and weighed. Its mass was 1.740 g. What was the percentage of each compound in the mixture

Answers

Answer:

See explanation

Explanation:

The reaction occurs as follows;

KBr(aq) + AgNO3(aq) ----> AgBr(s) + KNO3(aq)

Number of moles of AgBr formed = mass /molar mass =1.740 g/187.77 g/mol = 0.0093 moles

From the reaction equation;

1 mole of KBr yields 1 mole of AgBr

Hence the number of moles of KBr reacted = 0.0093 moles

Mass of KBr present = 0.0093 moles × 119g/mol = 1.11 g

Mass of KNO3 = 2.850 g - 1.11 g = 1.74 g

Percentage of KBr = 1.11 g/2.850 g × 100 = 38.9%

Percentage of KNO3 = 1.74 g/2.850 g × 100 = 61.1%

What is the acceleration of a 10kg object if a force of 3N is applied to it

Answers

Answer:

0.3kg/min

Explanation:

The formula for acceleration is a = f/m where f = force and m = mass.

a = 3/10

a = 0.3

Best of Luck

Identify the molecule with the strongest intermolecular force. H 2o chcl 3 c 6h 6 of 2.

Answers

Base on molecule given that is H₂O , CHCl₃, C₆C₆ and OF₂. The strongest intermolecular force is H₂O molecule.

How strong are H₂O , CHCl₃, C₆C₆ and OF₂ intermolecular force?C₆C₆ or Benzene is  determine a non polar molecule where the bonded with weak london dispersion forces.CHCl₃ or Trichloro methane is determine as a polar molecule where the bonded with weak dipole dipole interactions.OF₂ or Oxygen difluoride is determine as a polar molecule but the polarities direction has opposite direction that make them cancel out each other. Their bond are weak because of london dispersion forces.H₂O or Water is determine as a polar molecule where the bond is strong in hydrogen bonding.

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during photosynthesis, light energy from the Sun causes a reaction to take place. The products of photosynthesis are used in a reaction during the process of cellular respiration, which provides energy for cell processes.
Identify which reaction absorbs energy and which reaction releases energy.​

Answers

Answer:

chemical reactions which proceed with the release of heat energy are called exothermic reactions

Which of the following statements on HPLC modes is true? A. Increasing the polarity of the mobile phase decreases the elution time of polar compounds in normal-phase HPLC B. A non-polar stationary phase is used in normal-phase HPLC C. Compounds have a lower attraction to the mobile phase than to the stationary phase in displacement development D. A polar stationary phase is used in reversed-phase HPLC E. More polar compounds elute first in normal-phase HPLC

Answers

The following statements on HPLC modes are true is more polar compounds elute first in normal-phase HPLC (Option E).

The liquid chromatography (HPLC) is a technique in analytical chemistry employed for the separation, identification, and quantification of elements. It is considered a highly sensitive method, and it works by separating the components in a mixture with the assistance of a solvent under high pressure.

There are two modes of HPLC: Reversed-Phase HPLC (RP-HPLC) and Normal-Phase HPLC (NP-HPLC). In RP-HPLC, a nonpolar stationary phase, such as C18, is used, and polar solvents, such as water, are used as mobile phases. Polar stationary phases, such as silica gel, are used in NP-HPLC, while nonpolar solvents, such as hexane, are used as mobile phases.

More polar compounds have a greater affinity for the polar stationary phase than less polar compounds, which have a higher affinity for the nonpolar mobile phase in NP-HPLC. As a result, less polar compounds elute first in normal-phase HPLC.

Thus, the correct option is E.

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A 50,000 g septic tank reading reports that methane gas bubbles are present with a concentration of 17 ppm

Answers

Answer:

\(m_{solute}=0.85g\)

Explanation:

Hello there!

In this case, according to the given information for the parts per million of methane in this solution, it is possible for us to first write the equation for this unit of concentration as shown below:

\(ppm=\frac{m_{solute}}{m_{solvent}} *1x10^6\)

In such a way, since the septic tank has a mass of 50,000 g, the mass of methane into it is calculated as shown below:

\(m_{solute}=\frac{ppm*m_{solvent}}{1x10^6}\)

Now, we plug in the numbers to obtain:

\(m_{solute}=\frac{17*50000g}{1x10^6}\\\\m_{solute}=0.85g\)

Regards!

What is the electron concentration in si at 300 k with a boron doping of n_a=10e14 cm^-3

Answers

When doping Si with Boron at 300k, the electron concentration in it will be \(10^14 cm ^(-3)\) according to the effect of the dopant theory.

Born induces an acceptor level band in the bandgap of silicon as it is a third-group element. The equilibrium condition when we introduce a dopant like boron (B) is given by:

\(n × p = n_i^2 ×(q × (E_f - E_i) / (k × T))\)

q = elementary charge,

E_f = Fermi level,

E_i = intrinsic energy level,

k = Boltzmann's constant,

T= temperature.

By the effect of the dopant, we can find the electron concentration in silicon (Si).

temperature= 300 K

Doping concentration ( nₐ) = \(10^14 cm ^(-3)\)

Intrinsic carrier concentration = \(1.5 × 10^10 cm^(-3)\) (For silicon at 300 K )

In the presence of boron doping, the concentration of holes increases

The new concentration of holes = nₐ,

⇒ \(10^14 cm ^(-3)\)

n = nₐ

n =  \(10^14 cm ^(-3)\)

⇒ \(10^14 cm ^(-3)\)

Therefore, the electron concentration in silicon at 300 K with a boron doping concentration will be \(10^14 cm ^(-3)\).

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Sig fig 35 mm + 21.321 mm + 2.00005 mm =

Answers

Answer:

Significant Figures in 200.0

Result 200.0

Sig Figs 4 (200.0)

Decimals 1 (200.0)

Scientific Notation 2.000 × 102

E-Notation 2.000e+2

Downwelling is the process that moves cold, dense water from the ocean surface to the seafloor near the polar regions. how can downwelling affect the ocean water around the poles? it brings warm, nutrient-rich water to the ocean floor. it brings water that is low in oxygen to the ocean surface. it brings low salinity water to the ocean surface. it brings oxygen-rich water to the ocean floor.

Answers

Donwelling  is the process that moves cold, dense water from the ocean surface to the seafloor near the polar regions. Downwelling affect the ocean water around the poles as it brings oxygen - rich water to the ocean floor.

Downwelling occurs when the water on the surface of the sea becomes denser than the water beneath it and so it sinks. ocean water get denser when it gets cola or saltier.Most downwelling happens at the poles.

I f the air was warmer at the poles, then water wold be warmer too.so, without cold water there would be little downwelling.Oxygen in deep sea would have used up  and without strong downwelling , there is no way to replenish oxygen.

Hence, Downwelling affect the ocean water around the poles as it brings oxygen - rich water to the ocean floor.

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11) Significant figures are important because they indicate
A) the accuracy of a measurement.
B) the number of digits on a calculator.
C) the number of measurements.
D) the precision of a measurement.
E) the accuracy of the conversion factor

Answers

Significant figures are important because they indicate the precision of a measurement.

Precision:

The precision of a substance is defined as the degree to which two or more measurements agree with one another. It is incredibly precise but not always accurate to measure something if you weigh it five times and get 3.2 kg each time. Accuracy is not necessary for precision. You can learn how to be accurate but not precise by looking at the examples below. There are various categories of precision:

Repeatability:

The fluctuation that results from taking multiple measurements under the same circumstances in a short amount of time.

Reproducibility:

The variation occurs when several instruments, operators, and longer time periods are used in the same measurement process.

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PLEASE HELP I'LL GIVE U BRAINLIEST

PLEASE HELP I'LL GIVE U BRAINLIEST

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Answer:

files  

Explanation:

i had to answer the same question

What form of energy does the swinging pendulum represent?

Mechanical energy


Radiant energy


Chemical energy


Electrical energy

----------------------------------------------------------------------

At which position is the potential energy of the pendulum the greatest?

Position C



Position A



Position B



Position D

Answers

Answer:

The answer for the first question is Mechanical energy and the second one is position A.

Why is there no reaction with the following; Aluminium oxide + copper​

Answers

Aluminium takes the copper out of the bond, as aluminium is a more active metal than the copper. Therefore, the red metallic copper and gaseous hydrogen are released.

This is the Image for my question

This is the Image for my question

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Answer:

uhm

Explanation:

Which orders the activities from the greatest to least impact to reduce consumption of fossil fuels?(1 point)

carpool to work, walk to work, drive an electric car to work

walk to work, carpool to work, drive alone to work

drive an electric car to work, walk to work, carpool to work

drive alone to work, drive an electric car to work, carpool to work

Answers

Answer:

walk to work, carpool to work, drive alone to work

Explanation:

Determine the molar solubility of BiPO4 in a solution containing 0. 358 M K3PO4. The Ksp for BiPO4 is 1. 3 × 10^-23.

A) 5. 7 × 10^-15

B) 3. 6 × 10^-23

C) 1. 3 × 10^-13

D) 1. 5 × 10^-8

E) 8. 3 × 10^-18

Answers

The molar solubility of BiP\(O_4\) in a solution containing 0.358 M K3P\(O_4\) is 5.7 × \(10^{-15}\) M. Therefore, the correct answer is option A) 5.7 × \(10^{-15}\).

What is Molar Solubility?

Molar solubility is a measure of the maximum amount of solute that can be dissolved in a given amount of solvent at a specific temperature, expressed in moles per liter (mol/L). It is the concentration of a solute at equilibrium with its undissolved solid form, also known as the saturation concentration.

Let x be the molar solubility of BiP\(O_4\). Since BiP\(O_4\) dissociates according to the balanced equation:

BiP\(O_4\) ↔ \(Bi_3\)+ + P\(O_4_3-\)

The equilibrium concentrations can be expressed as:

[Bi3+] = x

[P\(O_4_3-\)] = 2x

The initial concentration of P\(O_4_3-\)- comes from the dissociation of K3P\(O_4\), which can be expressed as:

K3PO4 ↔ 3K+ + PO43-

The equilibrium concentration of PO43- can be expressed as:

[P\(O_4_3-\)-] = 0.358 M - 3x

Substituting these values into the solubility product expression, we get:

1.3 ×\(10^{-23}\) = x(2x)(x) / (0.358 - 3x)

Simplifying this equation gives:

8\(x^{3}\) - 6.408\(x^{2}\) + 0.8188x - 0.00007 = 0

Using a solver, we get x = 5.7 × \(10^{-15}\) M.

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The population census of a city shows that its population has grown in the last decade. This growth has surpassed the city’s ability to provide sufficient water to its people. The city is located about 10 miles from the ocean and has a dry climate. Suggest a technology to use in this city. Defend your choice with a valid explanation.

Answers

Answer:   Hydro-electricity

Explanation: After all it is technology right. The population can use the waves even the tides of the ocean's water to create electricity which is reliable. of course in the beginning it will be expensive but the result will be effective useful. The area  having a dry climate could be because of the winds that blow precipitating clouds away  but they can have a stable climate by planting more trees where rain can be processed within the geographical location. Finally, the problem of water supply can be fixed by installing water pipes to transport water to the community but in the process, water can be filtered or cleansed to prevent some diseases and social issues/calamities.

all credit to geography

bye

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