What is the dependent variable? Be specific. *
If a teacher washes the tops of the student
desks with rubbing alcohol daily, the
spread of germs in the classroom may be
diminished.Be specific when you write your answer HELPPPPP I NEED IT ASAP!

Answers

Answer 1
The dependent variable is what is BEING MEASURED. You could say the cleanliness or hygiene of the desks is what we are measuring after she’s done cleaning them

Related Questions

calculate the equilibrium concentration for the nonionized bases and all ions in a solution that is 0.25M

Answers

Answer:

The equilibrium concentration of [CH₃NH₂] = 0.23965 M.

The equilibrium concentration of CH₃NH₃⁺ and  OH⁻ =  0.01035 M respectively.

Explanation:

The first step is to write out the dissociation reaction. Therefore, the equation showing the dissociation is given as below;

CH₃NH₂ + H₂0   <--------------------------------------------------------> CH₃NH₃⁺ + OH⁻.

Kindly note that ''<----------->'' arrow shows that the reaction is an equilibrium reaction.

Therefore, at the start of the reaction [that is time, t =0], we have that the concentration of CH₃NH₂ = 0.25M, thus, the concentration of CH₃NH₃⁺  and  OH⁻ is zero respectively at this time, t =0.

At equilibrium, the concentration of CH₃NH₂ = 0.25M - x, thus, the concentration of CH₃NH₃⁺  and  OH⁻ is x respectively.

Therefore, kb =  4.47 × 10-4 = [CH₃NH₃⁺ ][OH⁻]/[CH₃NH₂].  Hence, slotting in the values into this equilibrium equation showing the relationship between kb and concentration of the species involved, we have that;

kb = 4.47 × 10⁻⁴ = x² /0.25 - x.

x² +  4.47 × 10⁻⁴x - 1.1175  × 10⁻⁴ = 0.

Solving this quadratic equation gives us the value of x as 0.01035 M.

Thus, the concentration of [CH₃NH₂] = 0.25 M - 0.01035 M = 0.23965 M

The equilibrium concentration of [CH₃NH₂] = 0.23965 M.

The equilibrium concentration of CH₃NH₃⁺ and  OH⁻ =  0.01035 M respectively.

why are copper pipes used in place of old lead pipes for plumbing systems?

Answers

copper is lightweight, which makes it easier to work with (saving on labor costs) and also easier to extend over long stretches without supports. It's also less expensive than steel and lead-free.

Match the following terms and definitions.
1. major ecological grouping of plants and animals
food chain
biome
environmental factor
decomposers
2. bacteria and fungi that break down dead matter
a state of change in which the end result is equal or
3.
balanced
the basic relationships that show how a community of plants,
animals, and bacteria live and grow and how these living
4. things are dependent on each other as well as the Sun, soil,
and other nonliving parts of their environment; a cycle of
relationships
line of plants and animals that shows the order in which
5.
organisms are eaten
a condition or conditions of the nonliving surroundings, such
6.
as light, temperature, water, and so on
ecosystem
dynamic equilibrium

Answers

Answer:

major ecological grouping of plants and animals

food chain

*biome*

bacteria and fungi that break down dead matter

*decomposers*

a state of change in which the end result is equal or

balanced

*dynamic equilibrium*

the basic relationships that show how a community of plants,

animals, and bacteria live and grow and how these living

*ecosystem*

things are dependent on each other as well as the Sun, soil,

and other nonliving parts of their environment; a cycle of

relationships

line of plants and animals that shows the order in which

*Food chain*

organisms are eaten

a condition or conditions of the nonliving surroundings, such

*environmental factor*

Explanation:

What is the atomic mass of element X

Answers

Answer:

Which one of the table is element X?

Explanation:

I have no idea and help!!!!!!!!!!!!!!!!!!!!!!!!!

Select the term that matches each definition:
a) A decrease in the solubility of an ionic compound as a result of the addition of a common ion.
b) The mass of a salt in grams that will dissolve in 100 mL of water.
c) A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved.
d) The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation.
e) The maximum number of moles of a salt that will dissolve in 1 L of solution.
*** Answer options for all questions: ***
- Solubility
- Molar Solubility
- Solubility product constant
- Common ion effect
- Saturated Solution

Answers

Answer: a) A decrease in the solubility of an ionic compound as a result of the addition of a common ion : Common ion effect

b) The mass of a salt in grams that will dissolve in 100 mL of water: Solubility

c) A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved: Saturated solution

d) The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation : Solubility product constant

e) The maximum number of moles of a salt that will dissolve in 1 L of solution : Molar solubility

Explanation:

Solubility is expressed usually as the mass of solute per 100 grams or 100 ml of solvent.

Molar solubility of a solid is expressed as the concentration of the dissolved solid in a saturated solution.

Solubility product constant is defined as the equilibrium constant in which a solid ionic compound is dissolved to produce its ions in solution. It is represented as [tex]K_{sp}[/tex]

The common-ion effect is the decrease in solubility of a sparingly soluble salt by the addition to the solution of a soluble compound with an ion in common with the precipitate.

Saturated solution is defined as the solution in which no more solute particles can be dissolved in the solvent.

Which of the following is NOT a strong electrolyte?
:

Answers:
Na2SO4
KI
CaCl2
LiOH
C6H1206

Answers

Answer:

C6H1206

Explanation:

C6H12O6 is a monomer of carbohydrates also known as glucose, so it is not an electrolyte at all.

________ and ________ fibres are obtained from animals ​

Answers

Answer:

Explanation:

Silk and wool

Answer:

silk and wool fibers are obtained from animals ​

Explanation:

good luck :)

Label each of the following changes as a physical change or chemical change. Give evidence to support your answer.


A catalytic converter changes nitrogen dioxide to nitrogen gas and oxygen gas

Answers

Answer:

A catalytic converter changes nitrogen dioxide to nitrogen gas and oxygen gas is a chemical change.

Explanation:

Hello.

In this case, since physical changes do not modify the molecular composition and structure of the material undergoing it whereas the chemical change does, for catalytic converters we should know they promote chemical reaction in which the composition is changed; for instance, for the given example, the following chemical reaction is the evidence:

[tex]2NO_2\rightarrow N_2+O_2[/tex]

As you can see, nitrogen and oxygen are no longer bonded but separated by themselves, therefore, this is a chemical change.

Best regards.

Based on the visible cell structure, which of the following statements is true?

Answers

Answer:I think it would be the third one.

Explanation:

a change of matter is a physical change
True or False​

Answers

Answer:

true

Explanation:

hope it helps

Answer:

I'm pretty sure it's true

Explanation:

20 characters

What is magma?

solid rock with a fine texture
cooled rock with large crystals
molten rock below Earth’s surface
flowing rock above Earth’s surface

Answers

Answer:

C. molten rock below Earth’s surface

Explanation:

Determine the value of the equilibrium constant (report your answer to three significant figures) for the following reaction if an equilibrium mixture contains 0.010 mol of solid PbBr2, and is 0.0100 M in Pb2+ ions and 0.0250 M in Br1- ions. Use the notation 4.31e-5 to indicate a number such as 4.31 x 10-5.

Answers

Answer:

6.25e-6 is the value of the equilibrium constant

Explanation:

we have this equation

[tex]PbBr(s) ----- Pb^{2+}(aq) + 2Br(aq)[/tex]

When at a state of equilibrium,

we have the concentration of Pb^2+ to be 0.01

we have the concentration of Br^- to be 0.025

the equilibrium constant concentration of both pure solids and liquid s are said to be equal to 1

[PbBR2] = 1

such tht

Keq = [Pb^2+] x [Br-]^2

we already know the values of these from the above.

0.01x0.025^2

= 0.01 x 0.000625

= 0.00000625

= 6.25 x 10^-6

= 6.25e^-6

A student was performing a separation of a mixture of organic compounds. The final step of the process involved a filtration of the analyte from an aqueous solution. After drying the filtered solid for a very short period time, they took the melting point of the compound. The measured melting point range of the compound was 106 – 113.8 0C, while the literature melting point of the compound was 122.3 0C. The above scenario is a very common one in organic labs.
1. Do you think their sample was pure?
2. If not, then what do you think could be the source of error.
3. How do you think this error can be minimized?

Answers

Answer:

1) No

2) The solvent contaminated the analyte

3) The solvent should be evaporated properly before washing and drying the analyte

Explanation:

During separation of organic compounds, solvents are used. These solvents are able to contaminate the analyte and lead to a large difference in melting point of solids obtained.

However, the error can be minimized by evaporating the solvent before washing, drying and melting point determination of the solid.

The solubility of silver(I)phosphate at a given temperature is 2.43 g/L. Calculate the Ksp at this temperature. After you calculate the Kspvalue, take the negative log and enter the (pKsp) value with 2 decimal places.

Answers

Answer:

Kps = 3.07 x 10⁻⁸

pKsp= 7.51

Explanation:

First, we calculate the molar solubility of  silver(I)phosphate (Ag₃PO₄) from the solubility in g/L by using its molar mass (418.6 g/mol):

2.43 g/L x 1 mol/418.6 g = 5.8 x 10⁻³ mol/L= s

Now, we have to write the ICE chart for the aqueous equilibrium of Ag₃PO₄ as follows:

     Ag₃PO₄(g) ⇄ 3 Ag⁺(aq) + PO₄³⁻

I                               0              0

C                            +3s           +s

E                            3s               s

Ksp = [Ag⁺]³[PO₄³⁻]= (3s)³s= 27s⁴

Since s=5.8 x 10⁻³ mol/L, we calculate Ksp:

Ksp= 27(5.8 x 10⁻³ mol/L)⁴= 3.07 x 10⁻⁸

The pKsp value is:

pKsp= - log Ksp = -log (3.07 x 10⁻⁸) = 7.51

Calculate the density of the aluminum cylinder with a diameter 0f 1.3 cm weighing 18 grams. Height of the cylinder is 5.2 Cm. Find percent error (Actual density of Aluminum is 2.7 g/cm3). (Formula for volume of cylinder is πr2h)

Answers

Answer:

Percent error = 3.7%

Explanation:

Given data:

Density of Al cylinder = ?

Weight of cylinder = 18 g

Diameter = 1.3 cm

Height = 5.2 cm

Actual density of Al = 2.7 g/cm³

Percent error = ?

Solution:

First of all we will calculate the volume of cylinder through given formula.

V = πr²h

r = diameter /2

V = 22/7 × (0.65 cm)²× 5.2 cm

V = 22/7 × 0.4225cm²× 5.2 cm

V = 6.89 cm³

Now we will calculate the density.

d = m/v

d = 18 g/ 6.89 cm³

d = 2.6 g/cm³

Percent error:

Percent error = measured value - actual value /actual value × 100

Percent error = 2.6g/cm³ - 2.7g/cm³ /2.7g/cm³  × 100

Percent error = 3.7%

Negative sign shows that measured or experimental value is less than actual value.

List the steps in the water cycle, in the correct order?

Answers

There are four main stages in the water cycle. They are evaporation, condensation, precipitation and collection. Let's look at each of these stages. Evaporation: This is when warmth from the sun causes water from oceans, lakes, streams, ice and soils to rise into the air and turn into water vapour (gas).

Which statement describes how this rock was likely formed?
slow cooling of magma beneath the surface of Earth
rapid cooling of magma beneath the surface of Earth
slow cooling of lava on the surface of Earth
rapid cooling of lava on the surface of Earth

I will mark Brainlyest

Answers

Answer:

A

Explanation:

Slow cooling of magma beneath the surface of earth

To solve this we must be knowing each and every concept related to rock and its formation. Therefore, the correct option is option A among all the given options.

What is rock?

Rock is a naturally occurring mineral aggregate that is cohesive and composed of one or even more minerals. These aggregates often take the shape of recognisable and mappable volumes and are the fundamental building block of the solid Earth.

Mineral crystals as well as the sorts of rocks that serve as their hosts cycle through many forms as geologic materials. Temperature, weight, time, and variations in the climate in the Earth's crust and on its surface all play a role in the process. Slow cooling of magma beneath the surface of Earth is the  statement that best describes the formation of rock.

Therefore, the correct option is option A.

To learn more about rock, here:

https://brainly.com/question/29767269

#SPJ2

How many moles of precipitate will be formed when 100.0 mL of 0.200 M NaBr is reacted with excess Pb(NO₃)₂ in the following chemical reaction?

2 NaBr (aq) + Pb(NO₃)₂ (aq) → PbBr₂ (s) + 2 NaNO₃ (aq)

Answers

Answer : The number of moles of precipitate, [tex]PbBr_2[/tex] formed will be 0.01 moles.

Explanation : Given,

Concentration of NaBr = 0.200 M

Volume of solution = 100.0 mL = 0.1 L      (1 L = 1000 mL)

First we have to calculate the moles of NaBr.

[tex]\text{Moles of NaBr}=\text{Concentration of NaBr}\times \text{Volume of solution in L}[/tex]

[tex]\text{Moles of NaBr}=0.200M\times 0.1L=0.02mol[/tex]

Now we have to calculate the moles of precipitate, [tex]PbBr_2[/tex] formed.

The balanced chemical reaction is:

[tex]2NaBr(aq)+Pb(NO_3)_2(aq)\rightarrow PbBr_2(s)+2NaNO_3(aq)[/tex]

From the balanced chemical reaction we conclude that:

As, 2 moles of NaBr react to give 1 mole of [tex]PbBr_2[/tex]

So, 0.02 moles of NaBr react to give [tex]\frac{0.02}{2}=0.01[/tex] mole of [tex]PbBr_2[/tex]

Therefore, the number of moles of precipitate, [tex]PbBr_2[/tex] formed will be 0.01 moles.

The number of mole of the precipitate (i.e PbBr₂) formed when 100 mL of 0.2 M NaBr react with excess Pb(NO₃)₂ is 0.01 mole

We'll begin by calculating the number of mole of NaBr in 100 mL of 0.2 M NaBr solution. This can be obtained as follow:

Volume = 100 mL = 100 / 1000 = 0.1 L

Molarity of NaBr = 0.2 M

Mole of NaBr =?

Mole = Molarity x Volume

Mole of NaBr = 0.2 × 0.1

Mole of NaBr = 0.02 mole

Finally, we shall determine the number of mole of the precipitate (i.e PbBr₂) produced from the reaction. This can be obtained as follow:

2NaBr(aq) + Pb(NO₃)₂(aq) → PbBr₂(s) + 2NaNO₃ (aq)

From the balanced equation above,

2 moles of NaBr reacted to produce 1 mole of PbBr₂.

Therefore,

0.02 mole of NaBr will react to produce = [tex]\frac{0.02}{2} \\\\[/tex] = 0.01 mole of PbBr₂.

Thus, the number of mole of the precipitate (i.e PbBr₂) produced from the reaction is 0.01 mole

Learn more: https://brainly.com/question/19572703

using this chemical might discolour equipment and surfaces​

Answers

Answer: do not know how to answer this

Explanation:

4. This is low wet land.
A. swamp
B. island
C. desert
D. peninsula

5. Japan is one of these.
A. island
B. peninsula
C. swamp
D. desert

Answers

Answer:

swap

Explanation: because it is a low wet land

Answer:

4.   swamp

5.   Island

Plz mark brainliest:)

What are two weather factors that are directly influenced by ocean currents
O Air density and humidity
O Air pressure and temperature
O Temperature and humidity
O Precipitation and air pressure

Answers

Explanation:

Preciptation and air pressure

Answer:

It is Temperature and humidity. C

Explanation:

I took the test and it said it was C

The energy associated with the motion and position of an object is called a.kinetic energy
b.potential energy
c.gravitational potential energy d.mechanical energy​

Answers

Answer: The answer is D.

Explanation:

The form of energy associated with the motion, position, or shape of an object is called mechanical energy. An object's mechanical energy is a combination of its potential energy and its kinetic energy. The basketball has both potential energy and kinetic energy.

Hope this helps!

Which of the following are decomposers?
O A. mice
O B. snakes
O C. fungi
OD. spiders
ASAP

Answers

Fungi is a decomposer
c. fungi is the correct answer
jsjkdkfk

Answer each of the following questions with increases, decreases, or does not change.
a) If the intermolecular forces in a liquid increase, the normal boiling point of the liquid increases .
b) If the intermolecular forces in a liquid increase, the vapor pressure of the liquid does not change .
c) If the surface area of a liquid increases, the vapor pressure increases .
d) If the temperature of a liquid decreases, the equilibrium vapor pressure increases .
Drag and drop your selection from the following list to complete the answer:
does not change decreases increases

Answers

Answer:

1) Increases

2) decreases

3) increases

4) decreases

Explanation:

When the intermolecular forces in a liquid increases, the greater vapour pressure of the liquid decreases accordingly.

Since the vapour pressure is proportional to temperature, as temperature increases, the vapour pressure increases alongside.

As intermolecular forces increases, the boiling point increases accordingly since more energy is required to break intermolecular bonds.

Lastly, the greater the surface area, tell greater the vapour pressure since more liquid surface area is now available.

How are salinity, temperature and circulation related?

Answers

Answer:

Salinity, along with temperature, determines the density of seawater, and hence its vertical flow patterns in thermohaline circulation. 2. Salinity records the physical processes affecting a water mass when it was last at the surface. Hope this helps!

Explanation:

The smallest form of matter that still retains the properties of an element

Answers

Answer:

atom

Explanation:

the atom is the smallest form.

Although there are smaller forms of matter (subatomic quarks, photons, electrons) an atom is the smallest that a form of matter could be that still possesses the properties of that element. An atom is classified into being a certain element based on how many protons it has.

A chemical engineer must calculate the maximum safe operating temperature of a high-pressure gas reaction vessel. The vessel is a stainless-steel cylinder that measures 41.0cm wide and 49.2cm high. The maximum safe pressure inside the vessel has been measured to be 3.70MPa. For a certain reaction the vessel may contain up to 2.50kg of dinitrogen difluoride gas.

Required:
Calculate the maximum safe operating temperature the engineer should recommend for this reaction. Write your answer in degrees Celsius. Be sure your answer has the correct number of significant digits.

Answers

Answer:

[tex]T=2.78x10^3 \°C[/tex]

Explanation:

Hello,

In this case, considering that the safe temperature may be computed via the ideal gas law as we now the pressure, mass and volume via the dimensions:

[tex]V=\pi r^2 h=\pi *(41.0cm)^2*49.2cm=2.60x10^5cm^3*\frac{1L}{1000cm^3} =260L[/tex]

The pressure in atm is:

[tex]P=3.70MPa*\frac{1x10^6Pa}{1MPa} \frac{1atm}{101325Pa} =36.5atm[/tex]

And the moles considering the mass and molar mass (66 g/mol) of dinitrogen difluoride (N₂F₂):

[tex]n_{N_2F_2}=2.50kg*\frac{1000g}{1kg}*\frac{1mol}{66g} =37.9mol[/tex]

In sich a way, by applying the ideal gas equation, which is not the best assumption but could work as an approximation due to the high temperature, the temperature, with three significant figures, will be:

[tex]T=\frac{PV}{nR}=\frac{36.5Pa*260L}{37.9mol*0.082\frac{atm*L}{mol*K} }\\ \\T=3053.6K-273.15\\\\T=2.78x10^3 \°C[/tex]

Best regards.

Calculate the sublimation pressure of the solid at the melting point of 400.00 K assuming that the enthalpy of sublimation is not a function of temperature.

Answers

This question is incomplete, the complete question is;

Tonksite is a solid at 300.00K.  At 300.00 K its enthalpy of sublimation is 66.00 kJ/mol. The sublimation pressure at 300.00 K is 5.00 × 10⁻⁴ atm

Calculate the sublimation pressure of the solid at the melting point of 400.00 K assuming that the enthalpy of sublimation is not a function of temperature.

Answer: the sublimation pressure of the solid at the melting point is  0.3727 atm

Explanation:

Given that;

T1 = 300 K

T2 = 400 K

H_sub = 66 kJ/mol = 66000 J/mol

P1 = 5.00 × 10⁻⁴ atm

p2 = ?

now using the expression

log( p2 / 5.00 × 10⁻⁴ ) = (H_sub / R ×  2.303 ) (( T2 - T1) / T1T2)

now we substitute of given values into the expression

log(p2/p1) = (66000 / 8.314 ×  2.303 ) (( 400 - 300) / 300 × 400 )

p2 = 0.3727 atm

therefore the sublimation pressure of the solid at the melting point is  0.3727 atm

A sample of an ideal gas has a volume of 2.23 L at 289 K and 1.05 atm. Calculate the pressure when the volume is 1.08 L and the temperature is 304 K. P= atm

Answers

Answer:

2.28 atm

Explanation:

V₁ = 2.33L,  V₂ = 1.08L

T₁ = 289K,  T₂ = 304K

P₁ = 1.05 atm, P₂ = ?

Where V₁ and V₂ are initial and final volume respectively

T₁ and T₂ are initial and final temperature respectively

P₁ and P₂ are initial and final pressure respectively

The formula to be used here is the general gas equation:

P₁V₁/T₁=P₂V₂/T₂

1.05 × 2.23/289 = P₂ × 1.08/304

P₂ × 1.08 × 289 = 1.05 × 2.23 × 304

P₂ = (1.05 × 2.23 ×304) ÷ (1.08 × 289)

P₂ = 711.82 ÷ 312.12

P₂ = 2.28 atm

calculate the amount of water produced by the combustion of 16 gram of methane​

Answers

Answer:  Since, the given weight of methane is 16 g, hence the water produced by the combustion of 16 g of methane is 36 g.

Explanation: Have a blessed day!

36 g
explanation: have a good day
Other Questions
Marco's daughter Elena has four boxes of toy blocks, with 50 blocks in each one. One day she dumps them all out on the floor, and some of them get lost. When Marco tries to put them away again, he ends up with 45 blocks in one box, 53 in another, 46 in a third, and 51 in the fourth. How many blocks are missing Do yall know what 4 1/26 is? Richard was hired by a hospital that uses electronic health records. Which of the following would most likely be included in his EHR training?A. Patient care, patient cost, and billing accuracyB. Communication skills, patient billing, trauma counselingC. Navigating home screens, accessing patient records, and patient schedulingD. Active listening skills, patient care, and administrative supervising What is the solution set of the quadratic inequality x^2-5 Which one of the codons below would stop the translation of mRNA by ribosomal subunits?UAG, UAA, UGAAUG, ATG, GTUCUG, AUG, GUAATG, AAG, AAA Help I need help asap You want a seat on the board of directors of Red Cow, Inc. The company has 260,000 shares of stock outstanding and the stock sells for $51 per share. There are currently 5 seats up for election. The company uses straight voting. How much will it cost you to guarantee that you will be elected to the board How many degrees are in a twelfth of a full turn? James gets $6 for his weekly allowance and spends $4 of it. His brother Mike gets $7 for his weekly allowance and spends $3 of it. Their mother's birthday is in 4 weeks. If they spend the same amount each week, how much money can they save together in that time to buy her present? 2 points Urbanization led to many of the ills of American society during the Progressive era.2 pointsTrueFalse anyone that knows it? 10 POINTSWhich tool can be used to measure the volume of a liquid to one decimal place?Options:a beakera graduated cylinderan Erlenmeyer flaska test tube Which is one of the transformations applied to the graph of f(x) = x2 to produce the graph of p(x) = 50 + 14x x2? a shift down 1 unit a shift left 7 units a shift right 1 unit a shift up 7 units Solve for x and y in the diagram below Liz is shipping a present to her friend. The shipping company charges one fee for the box, and another fee depending on the weight of the package. She pays $2 for the shipping box. The package weighs 9 pounds. If liz paid a total of $38, how much does the company charge per pound? Fahrenheit 451Write a paragraph on the imagery' from this text with evidence, as well as a second paragraph for the mood. What are some of the government requirements imposed on a public corporation that are not imposed on a private, closely held corporation? Discuss pros and cons of each The fraction whose denominator is 8 more than the numarator How many solutions does this system of equations have? What role reversal took place during the final illness of Eliezers father?