In a classroom, which comparison would a teacher most likely use for describing a mole?
a cup of water and a liter of oil
a dozen eggs and a dozen jellybeans
a jar of jellybeans and a gram of salt crystals
20 marbles in a bag and 10 large ice cubes

Answers

Answer 1
B That the answer (hope this helps)
Answer 2

Answer:

B

Explanation:

a mole is "a chemist's dozen" lol


Related Questions

Is mass conserved when 40 g of sodium hydroxide undergoes a chemical change during an interaction with 37g of hydrogen chloride? Use complete sentences to support your answer by explaining how this can be demonstrated. (10 points)​

Answers

Answer:

Mass is conserverd

Explanation:

Any chemical reaction must follow the law of conservation of mass. Meaning that mass cannot be created nor destroyed. Since all chemical reactions must follow this law, no matter what reaction happens, mass is conserved.

410X
412
412
410
183
186
183R
Which two are isotopes?

Answers

Answer:

412/410X and 412/410

Explanation:

Isotopes have same atomic number but different mass number.

HURRY PLEASE HELP
Four students are discussing the benefits and problems associated with using nuclear energy as alternative energy source. Which student has the strongest argument about using nuclear energy?
A. Nuclear power plants pollute the environment and causes cancer in populations that use nuclear energy instead of traditional electricity.
B. Nuclear power plants provide more energy than traditional coal plants; however, nuclear power plants also produce more greenhouse gases.
C. Nuclear power plants run a high risk of nuclear meltdown killing all the organisms in a 20 mile radius.
D. Nuclear power plants provide more energy than traditional coal plants and these plants do not produce greenhouse gases.

Answers

Answer:

A

Explanation:

its A

facts o.o

Nuclear power plants pollute the environment and causes cancer in populations that use nuclear energy instead of traditional electricity. Hence option A is correct.

What is nuclear power plant?

Nuclear power plant is defined as a particular kind of power plant that produces electricity by nuclear fission. Nuclear power plants use the heat generated by nuclear fission to transform water into steam in a controlled environment, which then powers generators to produce electricity.  Low-enriched uranium fuel is used in nuclear power plants to generate electricity through a process known as fission, which involves breaking uranium atoms in a nuclear reactor.

A clean energy source with no emissions is nuclear. It produces energy by fission, which is the splitting of uranium atoms to release energy. Without the toxic consequences that come from burning fossil fuels, electricity is produced using the heat from fission to produce steam, which turns a turbine.

Thus, nuclear power plants pollute the environment and causes cancer in populations that use nuclear energy instead of traditional electricity. Hence option A is correct.

To learn more about nuclear power plant, refer to the link below:

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2. Which test for iron(II) ions is conclusive ​

Answers

Answer:

please brainlist answer

Explanation:

The addition of K 3 Fe(CN) 6 to a solution causes the formation of a deep blue precipitate which indicates that iron(II) ions are present.

The conclusive test for iron(II) ions is the test by the use of potassium hexacyanoferrate III solution.

In qualitative analysis certain reagents are used to test for the presence of certain cations or anions. Those reagents react in a certain way with those reagents. Usually, a positive test may involve a color change, formation of a precipitate or evolution of a gas.

In the case of iron(II) ions, potassium hexacyanoferrate III solution is used in the conclusive qualitative test for the ion. A positive test involves the appearance of a deep blue precipitate.

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Describe how this instrument works.

Operation:

Answers

Answer:

Microscope

Explanation:

Answer:

its a telescope you see stars or plants

Explanation:

How many electrons are in the nucleus of an atom with an atomic number of
16?
O None. Electrons are not in the nucleus
08
O 16
O 32

Answers

Answer:

None. Electrons are not in the nucleus.

Explanation:

We know that an atom consist of electrons, protons and neutrons. Neutrons and protons are present inside the nucleus while electrons are present out side the nucleus. Electron has a negative charge and is written as e⁻. The mass of electron is 9.10938356×10⁻³¹ Kg . While mass of proton and neutron is 1.672623×10⁻²⁷Kg and 1.674929×10⁻²⁷ Kg respectively.

Symbol of proton= P⁺  

Symbol of neutron= n⁰  

The number of electron or number of protons are called atomic number while mass number of an atom is sum of protons and neutrons. The umber of protons and electrons are always equal to make the atom electrically neutral .

The atom having atomic number 16 have 16 electrons and these electrons are present out side the nucleus.

Hat is the answer for this

Answers

Answer:

C

Explanation:

Answer:

I think is A

Explanation:

Hope it helps

Which is the Lewis structure for H3PO4? An upper P is single bonded above to an O, and to the left, right, and below to an O single bonded to an H. The O above the P has three pairs of dots to the left, above, and below; the O's to the sides have pairs of dots above and below, and the O below the P has pairs of dots right and left. A central upper P is single bonded left, right, above, and below to upper Os. The O above the P is single bonded to upper H on the left and the right, and has two electron dots above it. The O below the P is single bonded to an H below, and has pairs of electron dots to the left and right. A central upper P is double bonded to an O above, and single-bonded to an upper O single-bonded to an upper H to the left and the right. The O above the P has three pairs of electron dots, to the left, above, and to the right; the O's to the right and left have pairs of dots above and below. A central upper P is bonded to an upper H above, an upper O below, and upper O's bonded to upper H's to the left and the right. The O below the P has three pairs of electron dots, to the left, right, and below; the other two O's have pairs of dots above and below. A central upper P is double bonded to an O above, and single-bonded to an upper O single-bonded to an upper H to the left and the right. The O above the P has three pairs of electron dots, to the left, above, and to the right; the O's to the right and left have pairs of dots above and below.

Answers

Answer:

It is A.

Explanation:

I took the test.

The Lewis structure shows the arrangement of valence electrons in H3PO4.

The Lewis structure gives us a picture of the number of valence electrons in a molecule. This is because, in a Lewis structure, the electrons in the molecule are shown as dots. A single line may be used to show shared electrons in a covalent bond.

The correct Lewis structure of H3PO4 is an upper P is single bonded above to an O, and to the left, right, and below to an O single bonded to an H. The O above the P has three pairs of dots to the left, above, and below; the O's to the sides have pairs of dots above and below, and the O below the P has pairs of dots right and left.

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J.J. Thomson's plum pudding model of the atom followed the discovery of
A)
negatively charged particles with a very small mass.
B)
positively charged particles with a very large mass.
0)
negative electrons that revolved around a positive nucleus.
D)
positively charged protons that were contained in a concentrated area.

Answers

the answer is A i think from the options though the answers are worded a bit weird

J.J. Thomson's plum pudding model of the atom followed the discovery of negatively charged particles with a very small mass. Thus, the correct option for this question is A.

Who was J. J. Thomson?

J.J. Thomson was a British physicist who discovered sub-atomic particles known as electrons within an atom. He also announced that atoms are made up of smaller components.

The plum pudding model is defined by Thomson in order to demonstrate that negatively charged sub-atomic particles known as electrons are surrounded by a volume of positively charged particles known as protons. It is one of the historical scientific model of the atom that governs all sorts of properties of sub-atomic particles.

Therefore, "negatively charged particles with a very small mass" is the discovery that follows J.J. Thomson's plum pudding model of the atom. Thus, the correct option for this question is A.

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Which is a valid reason why total dissolved solids (TDS) cannot be accurately calculated by conductivity alone?

Global warming has significantly increased the conductivity of water.

Big blobs of algae do not conduct electricity.

Fish poop changes the conductivity.

Ionic compounds may behave differently based on ion characteristics (e.g. charge or size).

Some dissolved solids may be nonelectrolytes.

Answers

Answer:

The correct option is the last option (Some dissolved solids may be nonelectrolytes)

Explanation:

Total dissolved solids (TDS) cannot be calculated by conductivity alone because conductivity involves ionic charges and there are solids that dissolve in water but do not carry ionic charges (and thus form non-electrolytes). Examples include sucrose (common sugar) and glucose. These two solids will dissolve in water but would not form ions that will carry ionic charges which are responsible for conductivity. Thus, if TDS only depends solely on conductivity, then a solution that contains dissolved sucrose will be wrongly accounted for as the sucrose will be omitted from the dissolved substances.

A valid reason why total dissolved solids (TDS) cannot be accurately

calculated by conductivity alone because some dissolved solids may be

non-electrolytes.

Conductivity means the ability of electric current to pass through a

substance and an electrolyte has a high conductivity when dissolved in

water.

Dissolved solids can't be measured by conductivity because not all

dissolved solids are electrolytes.

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Consider the two electron arrangements for neutral atoms A and B. What is the atomic number of A?
A - 1s?, 2s 2p6,35
B - 1s2, 2s 2p, 5s

Answers

Your answer is B: The outer electron of Adam B has moved to a higher energy state

A sample is found to contain 2.98x10^-10 g of salt. Express this quantity in nanograms.

Answers

This quantity = 0.298 nanograms(ng)

Further explanation

Mass is one of the principal quantities, which is related to the matter in the object

The main mass unit consists of 7 units of other than other units of mass such as quintals, tons, pounds, ounces:

Kilogram, kg

Hectogram, hg

Decagram, dag

gram, g

Desigram, with

centigram, cg

milligram, mg

Each unit descends then multiplied by 10, and if one unit increases then divided by 10

Conversion of other mass units:

10⁻³ g ⇒mg-milligrams

10³ g ⇒kg-kilograms

10⁻⁶ g ⇒µg-micrograms (mcg)

10⁶ g ⇒Mg-megagrams (tons)

10⁻⁹ g ⇒ng-nanograms

10⁹ g ⇒Gg-gigagram

10⁻¹² g ⇒pg-pikogram

2.98 x 10⁻¹⁰ g to nanograms(ng)

[tex]\tt 2.98\times 10^{-10}\times 10^9=0.298~ng[/tex]

5. Psilocybin is made of C 50.70%, H 6.03%, N 9.86%, 22.51%, P 10.90%. a. Find the empirical formula.​

Answers

The empirical formula : C₁₂H₁₇N₂O₄P

Further explanation  

The empirical formula is the smallest comparison of atoms of compound =mole ratio of the components

The principle of determining empirical formula

Determine the mass ratio of the constituent elements of the compound.   Determine the mole ratio by by dividing the percentage by the atomic mass

C

[tex]\tt \dfrac{50.7}{12}=4.225[/tex]

H

[tex]\tt \dfrac{6.03}{1}=6.03[/tex]

N

[tex]\tt \dfrac{9.86}{14}=0.704[/tex]

O

[tex]\tt \dfrac{22.51}{16}=1.407[/tex]

P

[tex]\tt \dfrac{10.9}{31}=0.352[/tex]

Divide by the smallest mole ratio(0.352)

C : H : N : O : P

[tex]\tt C\rightarrow \dfrac{4.225}{0.352}=12[/tex]

[tex]\tt H\rightarrow \dfrac{6.03}{0.352}=17[/tex]

[tex]\tt N\rightarrow \dfrac{0.704}{0.352}=2[/tex]

[tex]\tt O\rightarrow \dfrac{1.407}{0.352}=4[/tex]

[tex]\tt P\rightarrow \dfrac{0.352}{0.352}=1[/tex]

Determine the wavelength of the energy that needs to be absorbed for a 3p electron in chlorine to be promoted to the 4s subshell. Assume that Zeff=6 for a chlorine atom.

Answers

Answer:

The wavelength of the energy that needs to be absorbed  = 52.36 nm

Explanation:

For this study;

Let consider the Rydgberg equation from Bohr's theory of atomic model:

i.e.

[tex]\dfrac{1}{\lambda} = R_H (Z^*)^2( \dfrac{1}{n_1^2}-\dfrac{1}{n_2^2})[/tex]

where

Z* = effective nuclear charge of atom = Z - σ = 6

n₁ = lower orbit = 3

n₂ = higher orbit = 4

[tex]R_H[/tex] = Rydyberg constant = 1.09 × 10⁷ m⁻¹

λ = wave length of the light absorbed

[tex]\dfrac{1}{\lambda} = 1.09 \times 10^7}(6)^2( \dfrac{1}{3^2}-\dfrac{1}{4^2})[/tex]

[tex]\dfrac{1}{\lambda} = 1.09 \times 10^7}(36)( \dfrac{1}{9}-\dfrac{1}{16})[/tex]

[tex]\dfrac{1}{\lambda} = 392400000\times0.0486111111[/tex]

[tex]\dfrac{1}{\lambda} =19075000[/tex]

[tex]\lambda = \dfrac{1}{19075000}[/tex]

[tex]\lambda = \dfrac{1}{1.91\times 10^7 \ m^{-1}}[/tex]

[tex]\lambda = 5.236 \times 10^{-8} m[/tex]

[tex]\lambda = 52.36 \times 10^{-9} m[/tex]

[tex]\lambda = 52.36\ n m[/tex]

Therefore, the wavelength of the energy that needs to be absorbed  = 52.36 nm

22. In 4f12, the 12 stands for the

Answers

The 12 stands for the number of electrons that fill the f orbital

Further explanation  

In an atom there are levels of energy in the shell and sub shell  

This energy level is expressed in the form of electron configurations.  

Writing electron configurations starts from the lowest to the highest sub-shell energy level. There are 4 sub-shells in the shell of an atom, namely s, p, d and f. The maximum number of electrons for each sub shell is  

• s: 2 electrons  

• p: 6 electrons  

• d: 10 electrons and  

• f: 14 electrons  

4f¹² :

4 : number of shell

12 : the number of electrons that fill the f orbital

How many milliliters of a 3.4 M NaCl solution would be needed to prepare each solution?

a. 45 mL of a 0.10 M solution:
mL

b. 330 mL of a 0.074 M solution:
mL

Answers

Answer:

a. Approximately [tex]1.3\; \rm mL[/tex].

b. Approximately [tex]7.2\; \rm mL[/tex].

Explanation:

The unit of concentration "[tex]\rm M[/tex]" is equivalent to "[tex]\rm mol \cdot L^{-1}[/tex]", which means "moles per liter."

However, the volume of both solutions were given in mililiters [tex]\rm mL[/tex]. Convert these volumes to liters:

[tex]\displaystyle 45\; \rm mL = 45\; \rm mL \times \frac{1\; \rm L}{1000\; \rm mL} = 0.045\; \rm L[/tex].

[tex]\displaystyle 330\; \rm mL = 330\; \rm mL \times \frac{1\; \rm L}{1000\; \rm mL} = 0.330\; \rm L[/tex].

In a solution of volume [tex]V[/tex] where the concentration of a solute is [tex]c[/tex], there would be [tex]c \cdot V[/tex] (moles of) formula units of this solute.

Calculate the number of moles of [tex]\rm NaCl[/tex] formula units in each of the two solutions:

Solution in a.:

[tex]n = c \cdot V = 0.045\; \rm L \times 0.10\; \rm mol \cdot L^{-1} = 0.0045\; \rm mol[/tex].

Solution in b.:

[tex]n = c \cdot V = 0.330\; \rm L \times 0.074\; \rm mol \cdot L^{-1} = 0.02442\; \rm mol[/tex].

What volume of that [tex]3.4\; \rm M[/tex] (same as [tex]3.4 \; \rm mol \cdot L^{-1}[/tex]) [tex]\rm NaCl[/tex] solution would contain that many

For the solution in a.:

[tex]\displaystyle V = \frac{n}{c} = \frac{0.0045\; \rm mol}{3.4\; \rm mol \cdot L^{-1}} \approx 0.0013\; \rm L[/tex].

Convert the unit of that volume to milliliters:

[tex]\displaystyle 0.0013\; \rm L = 0.0013\; \rm L \times \frac{1000\; \rm mL}{1\; \rm L} = 1.3\; \rm mL[/tex].

Similarly, for the solution in b.:

[tex]\displaystyle V = \frac{n}{c} = \frac{0.02442\; \rm mol}{3.4\; \rm mol \cdot L^{-1}} \approx 0.0072\; \rm L[/tex].

Convert the unit of that volume to milliliters:

[tex]\displaystyle 0.0072\; \rm L = 0.0072\; \rm L \times \frac{1000\; \rm mL}{1\; \rm L} = 7.2\; \rm mL[/tex].

The definition of having to do with the physical properties and terrain of an area refers to the
term
environmental
forecasting
meticulous
topographical
adjacent

Answers

Answer:

Topographical

Explanation:

When it comes to questions such as this one, the thing that could help you the most is a dictionary. A dictionary is an alphabetically arranged listing of words that contains various information about those words, such as their definitions, examples, origin, pronunciation, etc.

The term the given definition refers to is topographical. Topography is the study of the forms and features of land surfaces. The topography of an area refers to its physical properties and terrain or their description (e.g. how they're shown on a map).

the illustration shows how sonar can be used to study the deep ocean which type of waves does sonar use

Answers

Answer: D. Sound Waves

Answer:

d

Explanation:

How did you organize the tiles in part A? Describe the method that you used.
Periodic table of numbers tiles

Answers

I need to know part A before I am able to answer this

Answer:

I ordered the tiles from left to right and top to bottom as the numbers kept increasing. The tiles were also organized based on the color and shape that they were. The tiles with the same color and shape were arranged in the same column.

Explanation:

In the modern periodic table, the elements are listed in order of increasing atomic number and elements having similar chemical properties naturally line up in the same column (group).

An overhead view of two people at the start of a maze. The person in a purple shirt has a line running forward, right, backward, right, forward, ending with an arrowhead pointing to a large gold star. The person in a green shirt has a line running forward, right, backward, right, forward, right, backward, right, forward, ending with an arrowhead pointing to a small gold star.
Zamir and Talia raced through a maze. Zamir walked 2 m north, 2 m east, 4 m south, 2 m east, 4 m north, 2 m east, 3 m south, 4 m east, and 4 m north. Talia walked 2 m north, 6 m east, 3 m south, 4 m east, and 4 m north.

Compare their distances:

Zamir walked
meters and Talia walked

Answers

Answer:

Zamir walked

27

meters and Talia walked

19

meters.

Explanation:

27 and 19

Answer:

zamir:27  Talia:19

Explanation:

i got it right on my test :)

Regional Metamorphism occurs when great masses of rock are exposed to pressure. What does this typically form?

Answers

Answer:

Gneiss forms by regional metamorphism from both high temperature and pressure. Quartzite and marble are the most commonly used metamorphic rocks.

Which describes a speed?
O A. Moving 8 meters in 2 seconds
O B. Falling down at 100 miles/hr
O C. Moving north at 40 km/hr
O D. Speed changing from 2 km/hr to 5 km/hr

Answers

Its A or B... Correct me if im wrong. :)

Naming inconic compounds and lots of iconic naming

Answers

if you just look up the answer it comes up btw!!

have a great day

Determine the volume (mL) of 15.0 M sulfuric acid needed to react with 45.0 g of
aluminum to produce aluminum sulfate.

Answers

Answer:

167 mL.

Explanation:

We'll begin by calculating the number of moles in 45 g of aluminum (Al). This can be obtained as follow:

Mass of Al = 45 g

Molar mass of Al = 27 g/mol

Mole of Al =?

Mole = mass /Molar mass

Mole of Al = 45/27

Mole of Al = 1.67 moles

Next, the balanced equation for the reaction. This is given below:

2Al + 3H2SO4 → Al2(SO4)3 + 3H2

From the balanced equation above,

2 moles of Al reacted with 3 moles of H2SO4.

Next, we shall determine the number of mole of H2SO4 needed to react with 45 g (i.e 1.67 moles) of Al. This can be obtained as:

From the balanced equation above,

2 moles of Al reacted with 3 moles of H2SO4.

Therefore, 1.67 moles of Al will react with = (1.67 × 3)/2 = 2.505 moles of H2SO4.

Thus 2.505 moles of H2SO4 is needed for the reaction.

Next, we shall determine the volume of H2SO4 needed for the reaction. This can be obtained as follow:

Molarity of H2SO4 = 15.0 M

Mole of H2SO4 = 2.505 moles

Volume =?

Molarity = mole /Volume

15 = 2.505 / volume

Cross multiply

15 × volume = 2.505

Divide both side by 15

Volume = 2.505/15

Volume = 0.167 L

Finally, we shall convert 0.167 L to mL. This can be obtained as follow:

1 L = 1000 mL

Therefore,

0.167 L = 0.167 L × 1000 mL / 1 L

0.167 L = 167 mL

Thus, 0.167 L is equivalent to 167 mL.

Therefore, 167 mL H2SO4 is needed for the reaction.

How does the number of atoms or molecules in a system affect its thermal energy?
A. A system with fewer atoms and molecules has more thermal energy.
B. A system with more atoms and molecules has more thermal energy.
C. The number of atoms or molecules does not affect the thermal energy of a system.
D. Thermal energy increases as the atoms and molecules in a system move more.

Answers

Answer:

D. Thermal energy increases as the atoms and molecules in a system move more.

Explanation:

Thermal energy is a form of kinetic energy possessed by molecules of a system. The measure of this kinetic energy in an atom is called heat.

The average kinetic energy of a system is the temperature.

According to the kinetic theory, the more the particles move, the more their thermal energy. Thermal energy is often predicated on the velocity of the particles of the medium.

The density of a substance is 1.63 grams per milliliter. What is the volume, in ml, of a sample of the substance with a mass of 5.40Kg? 1000 g = 1 kg

Answers

Answer:

############################

Explanation:


trioxocarbonate iv acid​

Answers

Answer:

Trioxocarbonate (iv) are salts derived from trioxocarbonate (iv) acid when it reacts with metals and metallic oxides. All trioxocarbonate (iv) salts of Sodium (Na), Potassium (K) and Ammonium(NH4+) are soluble while all others are insoluble.

True or False: Scientists use what they know about the properties of different molecules to separate mixtures. *

Answers

Answer:

True

Explanation:

Mixtures are substances with indefinite composition. They consist of two or more elements  and or compounds in any proportion by mass.

Their constituents retain their identities i.e. physical properties are retained. Their constituents reacts differently to changed conditions. They can easily be separated into constituents by physical methods.

From these properties we can clearly identify that to separate mixtures, we use the differences in the chemical properties of the constituents of the mixtures.

________________naturally helps cold-blooded animals warm up so that they can function.

Question 5 options:

Radiation


Convection


Warm Water


Heating pad

Answers

Answer:

Warm Water

Explanation:

In warm temperatures, cold-blooded animals are more active and can travel more quickly. This occurs because heat activated reactions provide energy to move muscles. In the absence of heat the animal becomes slow and sluggish. So they are usually inactive and rest when it is cold. As they do not need to feed much, they spend less time looking for food, so this life strategy works for them.

Brainliest?

Answer warm water Explanation:i have the same question

What two subatomic particles add up to make the mass?

Answers

protons and nuetrons :) ! hope this helps and please rate
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