What are the units for Rf values? Please help!

Answers

Answer 1

Answer:

Microwatts.

Explanation:

RF + EMF Unit Conversion Charts: Interpreting exposure levels. When measuring Radio Frequencies, the most common units of measurement are microwatts per square meter (µW/m2), microwatts per square centimeter (µW/cm2) and volts per meter (V/m).

Answer 2

Answer:

No units

Explanation:

In Thin Layer Chromatography (TLC), retention factor (Rf value) is found by taking the distance travelled by the spot divided by the distance of the solvent front. Rf value is a ratio of distances hence they have no units.

Mathematical derivation

The distance travelled by the spot is in cm, and that of the solvent front is also in cm. Thus, dividing the two units would give us no units for the Rf value.

What is TLC?

TLC is a technique used for separation and identification. The stationary phase is polar while the solvent is relatively nonpolar. Thus, the less polar substance is more attracted to the solvent (according to the principle of 'like attracts like') and travels further and thus have a higher Rf value.

To learn more about Rf values, check out: https://brainly.com/question/14393140


Related Questions

Andrew walks through his garden and observes that the shapes of dewdrops are not always the same. Suppose he wants to investigate using the scientific method. Which questions are testable questions that he can ask to look into the reasons for the different shapes?

Answers

Answer: A, C, E

Explanation: PLATO. all testable questions.

Which graph best shows an inverse relationship?

Answers

Answer:

b

Explanation:

just got done with this one

It’s b!!!!!!!!!!!!!!!!

Which of the following statements are not scientific hypotheses?

•Santa Claus exists.

The growth of corn in lowa depends on the amount of rain that falls.

•Theft is immoral.

•The bark of a specific tree is poisonous to mice

Answers

Answer:

.

Explanation:

1 and 3 aren’t a hypothesis

Keeping in mind the rules for significant digits, what is the product of 0.8954 m and 2.98 m?​

Answers

Answer: 3.240576

Explanation:

There are various ways of doing multiplication this is one of them

The wording "keep in mind the rules for significant digits" implies that we are to use these to show where the decimal place goes by approximating the answer. Then conducting the exact calculation.

Consider 0.8 as 8  

×

1

10

3

×

8

×

1

10

=

2.4

So the solution is some where a bit above 2.4

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Lets just use the numbers

Multiply both 0.8439 and 3.84 by 1000 to get rid of the decimal place. This makes thing more straight forward. So we end up with:

8439

×

38400

Split up the 38400 into 30000+ 8000 + 400

30000

×

8439

=

253170000

.

8000

×

8439

=

.

67512000

.

.

400

×

8439

=

.

.

3375600

−−−−−−−−−  

Add

                       

.

324057600

By our approximation we are expecting the form of

2.4

+

small amount

So the answer is  

3.240576

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Check by calculator:  

0.8439

×

3.84

=

3.240576

Caves are formed by: i)solution ii)oxidation iii)carbonation iv)hydration​

Answers

Answer:

i think its oxidation

Explanation:


What is the speed of a jet plane that flies 78500 km in 10.5 hours (in km/hr)?
Do not use decimal

Answers

S = d/t

S = 78500/10.5

S = 7,476 Knots

A wind up toy that is wound up and moving

Answers

Answer:

A wind-up toy is wound up and moving across level ground. The toy is speeding up.

Explanation:

this will or should helpyou

A Potassium isotope contains 19 protons, 19 electrons and 21 neutrons. What is its mass number? 40​

Answers

Answer:

17

Explanation:

you add 19+19 the subtract 21. I think

A  potassium isotope contains 19 protons, 19 electrons, and 21 neutrons, so the mass number is 40 as the mass number of the atom is the sum of the protons and the neutrons, the mass number is 40.

What is the significance of the mass number in the atom?

The mass number is significant as it is the sum of the number of protons and neutrons present in nucleus of an atom, which determines the atomic weight of an element and also determines its chemical properties and its position on the periodic table. Isotopes of an element have the same atomic number but a different mass number, so they have different properties than the original element.

Hence, a potassium isotope contains 19 protons, 19 electrons, and 21 neutrons, so the mass number is 40 as the mass number of the atom is the sum of the protons and the neutrons, the mass number is 40.

Learn more about the mass number in the atom here.

https://brainly.com/question/4408975

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110) Lake Michigan holds 1.3 x 10's gallons of water. If just Chicago removed water from the lake and it

never rained again, how many days would the water last? Chicago uses 1.2 x 109 gallons of water /day

gallons/day

Answers

You omitted what it was raised to the power in 1.3 x 10's gallons of water,  so i will put it up as   1.3 x 10^15 gallons of water and solve with it

Answer:1,083,333 days

Explanation:

Total amount of water held by lake Michigan= 1.3 x 10^15 gallons of water

Amount of water Chicago uses per day =Chicago uses 1.2 x 10^9 gallons of water /day

Therefore,

Number of days water would last if it doesnt rain =  Total gallons provided by lake Michigan/ Total gallons consumed per day

=1.3 x 10^15 gallons of water/ 1.2 x 10^9 gallons of water /day

= 1,083,333 days

A graduated cylinder is placed on an electronic balance, and the scale reads 78.32 g. 10.0mL of glycerine are added, and the scale reads 91.78 g. What is the density of glycerine

Answers

Answer:

1.346 g/mL

Explanation:

The density is defined as the mass of a substance per unit of volume.

In the problem, you add 10.0mL of glycerine. the mass change from 78.32g to 91.78g. The difference is the mass of the glycerine:

Mass glycerine: 91.78g - 78.32g = 13.46g

As the volume added was 10.0mL, the density, δ, in g/mL is:

δ =13.46g / 10.0mL =

1.346 g/mL

Eva buys a package of food, and the nutrition label says that one serving is equal to 36 grams and has 110 Calories. However, the box is printed with a label that says 0.150 pounds. If Eva eats the whole package, how many Calories will she have consumed?

Answers

Answer:74844

Explanation:

Answer:

208

Explanation:

(110 calories × 68.04 grams) ÷ 36 grams

= 208 calories

Got it right on my assignment

And experiment a student measures the speed of a toy car locations K through N as it rolls down a ramp based on the data collected in the table exclusion was shown by the student that the unbalanced forces acting on the toy car affect its average speed what reasoning lead to the interpretation of this data and conclusion

Answers

Answer:

B) The average speed of the car increases as distance traveled increases.

Explanation:

The unbalanced forces acting on the toy car affect its average speed, The average speed of the car increases as distance traveled increases. Therefore, option A is correct.

What do you mean by an average speed ?

The term average speed is defined as the total distance traveled by the object in a particular time interval. The average speed is a scalar quantity. It is corresponded to the magnitude and does not have direction.

Average speed is calculated by dividing the total distance something travels by the total amount of time it spends traveling.

Average speed = Total distance covered / Total Time. The S.I. unit of speed is meter per second.

The unbalanced forces acting on the toy car impact its average speed, The average speed of the car increases as distance traveled increases.

Thus, option A is correct.

To learn more about the average speed, follow the link;

https://brainly.com/question/12322912

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Your question is incomplete, most probably your question was

And experiment a student measures the speed of a toy car locations K through N as it rolls down a ramp based on the data collected in the table exclusion was shown by the student that the unbalanced forces acting on the toy car affect its average speed what reasoning lead to the interpretation of this data and conclusion

A.The average speed of the car increases as distance traveled increases.

B.The average speed of the car decrease as distance traveled increases.

C.The average speed of the car decreases as distance traveled decreases.

D. The average speed of the car increases as distance traveled decreases.

help? This is science btw​

Answers

the first choice. the greatest mass

List two things that do not change between isotopes of an element

Answers

Answer:

Explanation:

Because different isotopes have different numbers of neutrons, they do not all weigh the same or have the same mass. Different isotopes of the same element have the same atomic number. They have the same number of protons. The atomic number is decided by the number of protons.

Answer:

Because different isotopes have different numbers of neutrons, they do not all weigh the same or have the same mass. Different isotopes of the same element have the same atomic number. They have the same number of protons. The atomic number is decided by the number of protons.

18 grams
4 kilograms
8 kilograms

Answers

Answer:

1 18 grams

2 500g

4 960 grams

5 7 kilograms

Help me find the answer please

Which of the items shown here will protect you from a chemical burn? Select all that apply.

A hand in a rubber glove.
A fire extinguisher.
A pair of glasses with clear shields attached on the sides.
A power source.

Answers

Answer:1 & 2

Explanation:

Answer:

A. The rubber gloves and C. the protective glasses

Explanation:

I just answered this question and it was correct.

Hope this helps!!!!

Please mark my answer the Brainiest!!!!!!

Question 4
These are the uncharged particle located in the nucleus. The number of these tha
atom has is equal to its mass number minus its atomic number.
1. Protons
2.Nuclei
3.Neutrons
4.Electrons

Answers

The answer is
3. Neutrons
I hope that helped. Good Luck!

i know that they are all pure substances but what else?

Answers

Answer :Matter makes up everything visible in the known universe, from porta-potties to supernovas. And because matter is never created or destroyed, it cycles through our world. Atoms that were in a dinosaur millions of years ago—and in a star billions of years before that—may be inside you today.     To form water, however, hydrogen and oxygen atoms must undergo chemical changes. For a chemical change to occur, atoms must either break bonds and/or form bonds. The addition or subtraction of matomic bonds changes the chemical properties of the substances involved. Both hydrogen and oxygen are diatomic—they exist naturally as bonded pairs (H2 and O2, respectively). In the right conditions, and with enough energy, these diatomic bonds will break and the atoms will join to form H2O (water). Chemists write out this chemical reaction as:

2H2 + O2 → 2H2O

This equation says that it takes two molecules of hydrogen and one molecule of oxygen to form two molecules of water. Notice that there are the same number of hydrogen atoms and oxygen atoms on either side of the equation. In chemical changes, just as in physical changes, matter is conserved. The difference in this case is that the substances before and after the change have different physical and chemical properties. Hydrogen and oxygen are gases at standard temperature and pressure, whereas water is a colorless, odorless liquid.  

Ecosystems have many chemical and physical changes happening all at once, and matter is conserved in each and every one—no exceptions. Consider a stream flowing through a canyon—how many chemical and physical changes are happening at any given moment?

First, let’s consider the water. For many canyon streams, the water comes from higher elevations and originates as snow. Of course that’s not where the water began—it’s been cycled all over the world since Earth first had water. But in the context of the canyon stream, it began in the mountains as snow. The snow must undergo a physical change—melting—to join the stream. As the liquid water flows through the canyon, it may evaporate (another physical change) into water vapor. Water gives a very clear example of how matter cycles through our world, frequently changing form but never disappearing.

Light energy allows these bonds to break and reform to produce sugar and oxygen, as shown in the chemical equation for photosynthesis:

6CO2 + 6H2O + light → C6H12O6 (sugar)+ 6O2  

This equation says that six carbon dioxide molecules combine with six water molecules to form one sugar molecule and six molecules of oxygen. If you added up all the carbon, hydrogen, and oxygen atoms on either side of the equation, the sums would be equal; matter is conserved in this chemical change.

When animals in and around the stream eat these plants, their bodies use the stored chemical energy to power their cells and move around. They use the nutrients in their food to grow and repair their bodies—the atoms for new cells must come from somewhere. Any food that enters an animal’s body must either leave its body or become part of it; no atoms are destroyed or created.

Matter is also conserved during physical and chemical changes in the rock cycle. As a stream carves deeper into a canyon, the rocks of the canyon floor don’t disappear. They’re eroded by the stream and carried off in small bits called sediments. These sediments may settle at the bottom of a lake or pond at the end of the stream, building up in layers over time. The weight of each additional layer compacts the layers beneath it, eventually adding so much pressure that new sedimentary rock forms. This is a physical change for the rock, but with the right conditions the rock may chemically change too. In either case, the matter in the rock is conserved.

The bottom line is: Matter cycles through the universe in many different forms. In any physical or chemical change, matter doesn’t appear or disappear. Atoms created in the stars (a very, very long time ago) make up every living and nonliving thing on Earth—even you. It’s impossible to know how far and through what forms your atoms traveled to make you. And it’s impossible to know where they will end up next.  This isn’t the whole story of matter, however, it’s the story of visible matter. Scientists have learned that about 25 percent of the universe’s mass consists of dark matter—matter that cannot be seen but can be detected through its gravitational effects. The exact nature of dark matter has yet to be determined. Another 70 percent of the universe is an even more mysterious component called dark energy, which acts counter to gravity. So “normal” matter makes up, at most, five percent of the universe.

Explanation:

How many seconds are in .079 years? (conversation factors)

Answers

Answer:

2491344 seconds

Explanation:

By the way Google has a conversion system just in case you want to use it. Just google time conversion. It also does other types of conversion like Volume and Weight.

HELP 100 POINTS explain how you would separate the components of a dirty water mixture that consists of: • coffee grounds • garlic powder • vegetable oil • sodium chloride (table salt) • gravel and sand • water. For each step discuss what separation method you are using and why you chose that method​

Answers

Note that all detail explanation on why or how will be attached at the end

Step 1: Removing the Oil

Theoretically, step 1 and 2 can be alternated and preferably I would start with step 2, but I thought of one first. I would begin by setting up the liquid mixture in a funnel with a closed twist valve. Once the water mixture and oil has separated, I would slowly remove all the water, leaving the oil.

Step 2: Removing the Gravel and Sand

The second step is to filter out solids by using a sand filter. This filter is made by using a Styrofoam cup that has had small holes punched into the bottom with an open paperclip. The cup is filled with layers of clean washed gravel. The gravel will be layered by putting course gravel in the bottom and fine sand in the middle followed by course sand on the top. The gravel on the bottom stops the loss of sand out of the holes and the gravel on top stops the sand from washing out as a sample is poured.

Step 3: Removing the Coffee Grounds and Garlic Powder

You would start by lining a clean funnel with a coffee filter or something comparable. Then, you would add a spoonful or so of Charcoal to the funnel. Then you would pour the mixture of water, garlic powder, salt and coffee grounds into it.

Step 4: Removing Salt

You would preform a simple evaporation to remove the salt from the water. If the water is still needed, then you can preform a sealed distillation which has the same effect, but just keeps the water.

Step 5: Celebrate!

If you are doing this is a school, congratulations! you just finished your assignment/lab! If you are doing this in the wilderness for survival, congratulations! you won't die so soon!*

*The purification of water will not guarantee your extended survival in the wilderness, just extend the time in which you will not die of dehydration.™

Explanation:

Step 1 works because the density of oil and water are different, so as you let the liquid settle, the two liquids will separate into two sections. This allows you to funnel the water out. Step 2 work because the gravel and sand you want out cannot pass the sand-gravel filter you made (as long as it was made correctly) Step 3 works because the garlic powder and coffee grounds cannot pass the filter and the smell and colour that leaked into the water would be removed by the charcoal. Step 4 works because as water evaporates or is boiled off, the salt cannot evaporate with it, so it is left behind. Like how I was in the mall. Step 5 works because this was a long explanation and now you can go look at memes.

1.0250 - 0.00063 =
O 1.02
1.0243
1.02437
DONE

Answers

Answer:1.0243

Explanation: I think that is it

The answer is B aka 1.0250 :)

My teacher gave this assignment for homework, and I don’t get it. A little help please?

Answers

County: cell

State: Tissue

Country: Organ

Continent: Organ system

World: organism

(smallest to largest)

Which of the following metals is most reactive?
a. Mg
b. Rb
c. Cs
d. Li

Answers

the answer would be c :)

which best represents a particle containing 28 protons, 26 electrons,and 34 neutrons?

Answers

Answer:

This question lacks options, but the question can be answered based on knowledge of proton, electron and neutron number. The answer is:

62 Ni2+ particle

Explanation:

Nickel is a chemical element with atomic number 28. This means it has 28 electrons and 28 protons in its neutral atom. However, the isotope of nickel being described in the question has a mass number of 62. The mass number is calculated by adding the proton number with the neutron number. That is;

Mass number = number of protons + number of neutrons

Mass number = 28 + 34

Mass no. = 62

An element with mass number 62, which has lost two electrons to become positively charged (two positive charges) is described in the question. Hence, the particle that best fits this description is positively charged Nickel particle (Ni2+).

Ni2+ has 28 protons, 26 electrons (reduced by 2) and 34 electrons.

Note that, the 2+ charge is as a result of the loss of two electrons, hence, reducing the electron number by 2.

Which of the following is NOT a characteristic of metals?

Answers

I can’t see the question :/

Answer:

brittle is not a characteristic of medals.

ANSWER ASAPP
What is a compound?

Answers

Answer:

a compound is a substance that contains atoms of two or more chemical elements held together by chemical bonds. any combination of two or more parts, aspects, etc. a word formed from two existing words or combining forms.

Explanation:

a substance that contains atoms of two or more chemical elements held together by chemical bonds. any combination of two or more parts, aspects, etc. a word formed from two existing words or combining forms.

Answer:

a thing that is composed of two or more separate elements/mixture !

i hope this helps !

Block A has a mass of 5g and a volume of 15mL. What is the density of block A? Will it float in water (density of water is 1.0 g/mL) Don't forget the units!! PLSSSS PLSSS PLSSS HELP I WILL MARK BRAINLIEST AND HELP WITH UR QUESTIONS I PROMISE!!!!

Answers

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

From the question

mass of block = 5 g

volume = 15 mL

The density of the block is

[tex]density = \frac{5}{15} = \frac{1}{3} \\ = 0.33333333...[/tex]

We have the final answer as

0.33 g/mL

The block will float on water since it's density is less than that of water which is 1 g/mL

Hope this helps you

How many significant figures are in 320001

Answers

there are 6. looked it up

name two liquid fuels obtained from petroleum

Answers

Answer:

Diesel and kerosene.

Hope it helps :)

Answer:

Gasoline

Diesel

Kerosene

LPG

Rethanol

Ethanol

Butanol

Which of the following is NOT an extensive property?

Answers

Answer:

Density

Explanation:

It's an intensive property because it doesn't depend on mass

Other Questions
HEY GUYS PLEASE HELP JUST LABEL THEM 1 2 3 and tell me true or false The following cost data pertain to the operations of Rademaker Department Stores, Inc., for the month of March: Corporate headquarters building lease $ 94,000 Cosmetics Department sales commissions-Northridge Store $ 6,600 Corporate legal office salaries $ 58,600 Store manager's salary-Northridge Store $ 11,600 Heating-Northridge Store $ 12,600 Cosmetics Department cost of sales-Northridge Store $ 32,600 Central warehouse lease cost $ 7,600 Store security-Northridge Store $ 14,600 Cosmetics Department manager's salary-Northridge Store $ 5,600 The Northridge Store is just one of many stores owned and operated by the company. The Cosmetics Department is one of many departments at the Northridge Store. The central warehouse serves all of the company's stores. What is the total amount of the costs listed above that are direct costs of the Cosmetics Department An advantage of light microscopes compared to electron microscopes is that light microscopesallow you to view the surface of cells in greater detail than electron microscopes have a higher magnification capability because they use natural light allow you to view living cells, while electron microscopes do nothave a greater resolution available because they use white light need help asap !!!!!!!! You have $60 and your sister has $120. You are saving $7 per week and your sister is saving $5 per week. How long will it be before you and your sister have the same amount of money? 4. A train traveled 300 miles in 2.5 hours. At this rate, how far would the train travel in 9 hours?HELP PLEASE Look at the picture of the prism separating light. Which explains why a prism can separate sunlight into a rainbow of all the visible colors? Right triangle prism with beam of white light touching its right corner and beam of colored light coming out from its base Question 4 options: A. Light of each wavelength travels at a different speed through a vacuum. B. The glass of a prism absorbs some colors and transmits others. C. Light of each wavelength is refracted at a different angle. D. The prism reflects light of each wavelength at a different angle. The Triangular Trade is a large part of what made slavery so successful in the colonies. What is the best explanation for where the Triangular Trade gets its name? Identify two ways Helen yoshida shares her research with the public.Can someone plz answer this question cuz it's due tomorrow 6. A student driver travels at a speed of 3km/h for an hour and a half. Whatdistance does it travel? solve please: 40=8d What are two types of oligarchies?theocracy and monarchydictatorship and theocracycommunism and dictatorshiptheocracy and communism factorize : 8a-b An automobile travels 471 miles in 8 hours.183What is the average speed of the automobile to the nearest mile per hour? The mushrooms thrived without hurting trees. Value systems do not affect spending True or False? Which of the following shows the correct location of Georgia?A Georgia is located in the Southern Hemisphere.B Georgia is located south of Mexico and north of Canada.C Georgia is located on the west coast of the United States.D Georgia is located on the east coast of the United States. The midpoint of AB is M(1, -1). If the coordinates of A are (7,-4), what are thecoordinates of B? Solve the system of linear equations by elimination. 12x - 7y = -2 8x + 11y = 30 A painting operation is performed by a production worker at a labor cost of $1.40 per unit. A robot spray-painting machine, costing $15,000, would reduce the labor cost to $.20 per unit. If the device would be valueless at the end of 3 years, what is the minimum number of units that would have to have been painted each year to justify the purchase of the robot machine