How are the elements arranged in the modern periodic table?
O A. According to atomic number
B. According to atomic mass
C. According to the number of neutrons
O D. According to the number of electrons

Answers

Answer 1
According to atomic
Answer 2

Answer:

A

Explanation:


Related Questions

When N2gas is passed through water at 293k.how many moles of N2 dissolve in 1litre water

Answers

Answer: 7 milimoles of [tex]N_2[/tex] dissolve in 1 litre water.

Explanation:

Given:  [tex]N_2[/tex] gas is passed through water at 293K.

Assumption :[tex]N_2[/tex] exerts a partial pressure of 0.987 bar.

Take : Henry's constant [tex]p_N_2[/tex] = 76.8 Kbar

[tex]K_H=76800[/tex]

To find : Number of moles of  [tex]N_2[/tex] gas dissolve in 1 litre water.

According to Henry's law,

[tex]p_N_2=K_HX_{N_2}[/tex]

[tex]\Rightarrow\ 0.987=76800X_{N_2}[/tex]

[tex]\Rightarrow\ X_{N_2}=\dfrac{0.987}{76800}=0.0000128515625\approx1.29\times10^{-5}[/tex]

moles in 1 liter  of water = [tex]\dfrac{1000}{18}=55.56\ [\text{Molar mass of }H_2O=18\ g][/tex]

Let n= moles of nitrogen

Total moles = 55.56+n

So,

[tex]X_{N_2}=\dfrac{n}{55.56+n}=1.29\times10^{-5}\\\\\Rightarrow\ 55.56\times1.29\times10^{-5}+1.29\times10^5n=n\\\\\Rightarrow\ n- 1.29\times10^5n=0.000714033\\\\\Rightarrow\ 0.999987n=0.000714033\\\\\Rightarrow\ n\approx7\text{ milimoles}[/tex]

Hence, 7 milimoles of [tex]N_2[/tex] dissolve in 1 litre water.

Which electrons are the valence electrons of the atom?
O A. The electrons closest to the nucleus
O B. The electrons that have lost their charge
O C. The electrons farthest away from the nucleus
O D. The electrons that have entered the nucleus

Answers

Answer:

[tex]\boxed{C}[/tex]

Explanation:

The electrons farthest away from the nucleus are the valence electrons of an atom.

The valence electrons are the electrons orbiting in the last shell around the nucleus.

Answer:

Option C

Explanation:

The electrons that are the farthest away from the nucleus are valence electrons. These are electrons are present in the outermost shell which is also called valence shell.

The client had the following for dinner: 8 ounces of pears 8 ounces of ginger ale 8 ounces of peaches 1 chicken tenders meal 1 popsicle (40 mL) 8 ounces of liquid meal supplement (i.e. Ensure®) What is the client's total intake?

Answers

Answer:

Client's total intake = 32 ounce of liquid meal supplement

Explanation:

Given:

Meal take

8 ounces of pears

8 ounces of ginger

8 ounces of peaches

liquid meal supplement = 8 ounces

Find:

Client's total intake.

Computation:

Client's total intake = 8 ounces of pears + 8 ounces of ginger + 8 ounces of peaches + 8 ounces liquid meal supplement  

Client's total intake = 32 ounce of liquid meal supplement

6. A diamond contains 5.0 ×10^21 atoms of carbon. What amount(moles) of carbon and what mass (grams) of carbon are in this diamond? *
a. 0.008303 and 0.0997
b. 0.008303g and 0.0997mol
c. 0.008303amu and 0.0997
d. 0.008303 and 0.0997amu

Answers

Answer:

0.008303 mol and 0.0997 g

Explanation:

From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.022×10²³ atoms.

This implies that 1 mole of carbon also contains 6.022×10²³ atoms.

Next, we shall determine the mole of carbon that contains 5.0×10²¹ atoms. This can be obtained as follow:

1 mole of carbon contains 6.022×10²³ atoms.

Therefore, Xmol of carbon will contain 5.0×10²¹ atoms i.e

Xmol of carbon = 5.0×10²¹ / 6.022×10²³

Xmol of carbon = 0.008303 mole

Therefore, 0.008303 mole of carbon contains 5.0×10²¹ atoms.

Finally, we shall determine the mass of carbon. This can be obtained as follow:

Mole of carbon = 0.008303 mole

Molar mass of carbon = 12.01 g/mol

Mass of Carbon =.?

Mole = mass /Molar mass

0.008303 = mass of carbon/12.01

Cross multiply

Mass of Carbon = 0.008303 x 12.01

Mass of Carbon = 0.0997 g.

Consider a gas in a container that can adjust its volume to maintain constant pressure. Suppose the gas is cooled. What happens to the gas particles with the decrease in temperature? What happens to the volume of the container?

Answers

Answer:

The volume will also decrease.

Explanation:

This illustration clearly indicates Boyle's law.

Boyle's law states that the volume of a fixed mass of gas is directly proportional to the absolute temperature, provided the pressure remains constant. Mathematically, it is represented as:

V & T

V = KT

K = V/T

V1/T1 = V2/T2 =... = Vn/Tn

Where:

T1 and T2 are the initial and final temperature respectively, measured in Kelvin.

V1 and V2 are the initial and final volume of the gas respectively.

From the illustration above, the volume is directly proportional to the temperature. This implies that as the temperature increases, the volume will also increase and as the temperature decreases, the volume also will decrease.

Determine the rate of a reaction that follows the rate law: rate = k[A]^m[B]^n, where: k = 0.2, [A] = 3 M, [B] = 3 M, m = 1, n = 2 A. 1.2 (mol/L)/s B. 27 C. 1.8 D. 5.4

Answers

[tex]7.408 \;X 10 ^ {-3} m^{-2} s^{-1}[/tex]  is rate of a reaction when k = 0.2, [A] = 3 M, [B] = 3 M, m = 1, n = 2 .

What is the rate of a reaction?

The rate at which the concentration of reactant or product participating in a chemical reaction alters is called the rate of reaction.

Rate of reaction = [tex]\frac{change \;in \;concentration}{time}[/tex] =  (mol/litre)/time.

m= 1 and n = 2

[tex]rate = K [A] [B]^2[/tex]

[tex]0.2 = K X 3 X 3 ^2[/tex]

K =   [tex]\frac{0.2 }{27 }[/tex]

K =   [tex]7.408 \;X 10 ^ {-3} m^{-2} s^{-1}[/tex]

Hence, [tex]7.408 \;X 10 ^ {-3} m^{-2} s^{-1}[/tex]  is rate of a reaction when k = 0.2, [A] = 3 M, [B] = 3 M, m = 1, n = 2 .

Learn more about the rate of a reaction here:

https://brainly.com/question/8592296

#SPJ2

Answer: 7.4 10-3

Explanation:

7.4 10-3 this is right ong

Which of the following is an aldehyde?

Answers

Answer:  [tex]CH_3CH_2CH_2CHO[/tex] has aldehyde functional group.

Explanation:

Functional groups are specific group of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules.

A.  [tex]CH_3CH_2CH_2COCH_3[/tex] has ketone [tex]C=O[/tex] functional group .

B.  [tex]CH_3CH_2CH_2COOH[/tex] has carboxylic acid [tex]COOH[/tex] functional group .

C.  [tex]CH_3CH_2CH_2CHO[/tex] has  aldehyde [tex]H-C=O[/tex] functional group .

D. [tex]CH_3CH_2CH_2COOCH_3[/tex] has ester [tex]RO-C=O[/tex] functional group .

Thus [tex]CH_3CH_2CH_2CHO[/tex] has aldehyde (CHO) group.

what is the smallest particle which prossesses the properties of a compound called?​

Answers

Answer:

Molecule

Explanation:

Compounds are chemical substances comprising of two or more elements. The smallest particle contained in a compound is the MOLECULE. Molecules are combinations of atoms (same or different) of an element held together by a chemical bond.

Since a compound is a molecule with two or more elements combined, the chemistry of the molecules contained in a compound determines its chemical properties. This means that the molecules of a compound are responsible for the interactions of a compound in a chemical reaction. Examples of molecules are H2O, N2, O3 etc.

Where are electrons found in the atom?
O A. Within the isotopes of the atom
O B. Within the nucleus of the atom
O C. All at the same distance from the nucleus
O D. At different distances from the nucleus

Answers

Answer:

D. At different distances from the nucleus

Explanation:

Electrons are found outside the nucleus on electron shells.

These electron shells extend outwards from the nucleus, so the electrons are found at different distances further away from the nucleus if they are on different electron shells.

someone plz plz answer this hurry plz it

Answers

Answer:

b

Explanation:

Which quantity can be calculated using the equation E=MC^2

Answers

Answer:

The energy needed to split an atom into separate protons, neutrons, and electrons

Explanation:

The equation E = MC^2 is developed by Einstein’s Special Relativity Theory

where,

E = Energy

M = mass

C = speed of the light

The energy should be measured in Joules i.e J

The mass should be measured in Kilogram i.e Kg

And, the speed of the light should be measured in meters per second i.e ms-1

The C should be squared

Now the energy is required to divided into three particles i.e protons, electrons and neutrons

It also needs to allocate the nucleus into distinct protons and neutrons that we called binding energy of nuclear

And if the energy is required to take off an electron from an atom we called the energy of ionization

And if the energy is required to add an electron to an atom so we called it affinity of electron

Which event is most likely occurring? diffusion because particles move from regions of high concentration to regions of low concentration diffusion because particles move from regions of low concentration to regions of high concentration effusion because there is a movement of a gas through a small opening into a larger volume effusion because there is a movement of a gas through a large opening into a smaller volume

Answers

Answer: c

Explanation: effusion because there is a movement of a gas through a small opening into a larger volume

Which of the following has the smallest radius ? A. Br B. I C. I- D. Br-

Answers

Answer:

A. Br

Explanation:

Atomic radius increases down the group. As the increase in the attractive force of the nucleus increases owing to increase in the size of its positive charges, extra electrons are added to the shells to more than counterbalance this effect down the group hence the atomic radius becomes larger. Iodine has a larger atomic radius than bromine.

Secondly, the ionic radius of a negative ion is greater than its corresponding atomic radius since a negative ion is formed by adding a negative charge (electron) to the atom thus making it bigger. Hence the radius of I^- is greater than that of Br^-.

This means that Br atom must possess the smallest radius among the options listed.

Answer:

D

Explanation:

Br-

Why does this experiment need a water pump?

Answers

Answer:

because the water/air needs to be pumped out.

Explanation:

hoped this helped! (just give it a 1 star if it didn't)

A large scuba tank with a volume of 18 L is rated for a pressure of 220 bar. The tank is filled at 20 °C and contains enough air to supply 1860 L of air to a diver at a pressure of 2.37 atm (a depth of 45 feet). Was the tank filled to capacity at 20 °C?

Answers

Answer:

Yes, at 20 °C the tank was filled to full capacity

Explanation:

Given;

let initial pressure, P₁ = 2.37 atm

let initial volume, V₁ = 1860 L

let final pressure, P₂ = 220 bar = 217.123 atm

let final volume, V₂ = ?

Subject the air volume (1860 L )  at 2.37 atm to the tank rating (220 bar)

Ideal law is given by;

PV = nRT

At a fixed mole and gas temperature, the equation becomes;

P₁V₁ = P₂V₂

V₂ = (P₁V₁) / P₂

V₂ = (2.37 x 1860) / 217.123

V₂ = 20.3 L

After subjecting the air volume to tank rating, the volume of the air at 220 bar is 20.3 L which is greater than tank volume (18 L).

The extra 2.3 L can be assumed to be compressed gas volume due to the given (lower) temperature.

Thus, at 20 °C the tank was filled to full capacity.

HELP PLS!! WILL GIVE BRAINLIEST What is a catalyst? A a substance that slows a reaction down without being used up itself in a reaction. B a substance that is used up while speeding up a reaction. C a reactant that is added to speed up a reaction. D a substance that increases the rate of a reaction without being used up itself in a reaction.

Answers

Answer:

D a substance that increases the rate of a reaction without being used up itself in a reaction.

Explanation:

Examples are

ammonia synthesis ==> iron

sulfuric acid manufacture ==> nitrogen(II) oxide, platinum

cracking of petroleum==> zeolites

hydrogenation of unsaturated hydrocarbons ==> nickel, platinum, or palladium

I hope it helps

Answer:

Hey there!

The correct answer would be D. "a substance that increases the rate of a reaction without being used up itself in a reaction."

Hope this helps :)

what is the scientific name for the layer of gas that surrounds the earth A. hydrosphere B. biosphere C. atmosphere D. lithosphere

Answers

Answer:

hydro

Explanation: hydrogen

Answer:

C. Atmosphere

Explanation:

First, let’s define each answer choice.

Hydrosphere: all of the water on Earth

Biosphere: the global ecosystem where organisms live

Atmosphere: the envelope of gases around the planet

Lithosphere: the outermost part of the Earth( the crust and upper mantle)

The question asks us to find the scientific name for the layer of gas that surrounds the Earth. The best choice is C. Atmosphere.

Triangle DEF is congruent to TriangleD'EF' by the SSS theorem. Which single rigid transformation is required to map TriangleDEF onto TriangleD'EF'? dilation reflection rotation translation

Answers

Answer:

B. reflection

Explanation:

Rigid transformations are methods involved in changing the dimensions or orientation of a given figure. The methods are; dilation, rotation, translation and reflection.

Reflection is the process in which a given figure is turned or flipped with respect to a point or line of reference.

In the given question,

ΔDEF ≅ ΔD'EF' (Side-Side-Side congruence property)

This implies that ΔDEF was reflected about point E to produce ΔD'EF'. Thus the required rigid transformation is reflection.

Answer:

Is C - Rotation

Explanation:

I have right on my test

What statement discribes the relationship of voltage and current

Answers

Answer:

Explanation:

Ohm's Law. The relationship between voltage, current, and resistance is described by Ohm's law. This equation, i = v/r, tells us that the current, i, flowing through a circuit is directly proportional to the voltage, v, and inversely proportional to the resistance, r.

The figure shows a graph of Allison’s walk to school. She follows the black vectors to get to her school. Which if the following best describes her walk?

Answers

Answer:

Allison walks 5 blocks west and 3 blocks south.

Explanation:

Vectors have both magnitude and direction. The attached figure shows the graph of Allison’s walk to school. She follows the black vectors to get to her school.

The first vector on the horizontal axis points towards west and there are 5 blocks. Initially, she walks 5 blocks in west direction.

The second vector points in the negative vertical axis. It means that she walks  3 block in south direction.

Hence, the correct option is (D) i.e. Allison walks 5 blocks west and 3 blocks south.

Place the following substances in order of decreasing vapor pressure at a given temperature: BeF2, CH3OH, OF2?
(a) OF2 > BeF2 > CH3OH
(b) BeF2 > OF2 > CH3OH
(c) BeF2 > CH3OH > OF2
(d) CH3OH > OF2 > BeF2
(e) OF2 > CH3OH > BeF2

Answers

Answer:

(b) BeF2 > OF2 > CH3OH

Explanation:

The degree and type of intermolecular forces present in a substance influences its vapour pressure considerably. The greater the magnitude and strength of intermolecular forces in the substance, the lower the vapour pressure of the substance.

BeF2 molecules are held together by weak vanderwaals forces hence BeF2 will exhibit the least degree of intermolecular interaction and have the highest vapour pressure. OF2 molecules are bound together by dipole interactions hence it will exhibit a lower vapour pressure compared to BeF2. CH3OH molecules form hydrogen bonds with water molecules hence it will exhibit the least vapour pressure among the trio.

What is a scientific question?
O A. One that everyone agrees on
OB. One that only scientists ask
O c. One that is answered through observation
O D. One that never changes

Answers

Answer:

O c. One that is answered through observation

I used process of elminations so

Explanation:

One that everyone agrees one doesnt mean it's accurate.

Only the one that scientists ask doesnt make sense

One that never changes and One that is answered through observation.... So C

How would you measure the mass and weight of an object?

Answers

Answer:

Weight = mass × earth's gravitational acceleration

Explanation:

Follow the following steps to measure the mass and weight of an object:

Measure the mass of the object using an accurate measuring scale.Multiply the mass of that object with earth's gravitational  acceleration which is approximately 9.8 N/kg

This law relates a planet's orbital period and its average distance to the Sun.
The orbits of planets are ellipses with the Sun at one focus.
The speed of a planet varies, such that a planet sweeps out an equal area in equal time frames.

Answers

Answer:

These are Kepler's Laws of Planetary Motion

Explanation:

Answer:

its Keplers third law,

then first law,

then second law

Explanation:

Why does anhydrous aluminium chloride have lower melting point than anhydrous aluminium fluoride?

Answers

Answer:

Explanation:

Molecule of aluminium fluoride is more polar than molecule of aluminium chloride . It is so because fluorine is more electronegative than chlorine . On Pauling scale , the electronegativity of fluorine is 3.98 whereas that of chlorine is 3.16 . Hence in aluminium fluoride , there is stronger inter molecular bonding because of  more polar nature of molecules .  In aluminium chloride  , there is weaker  inter molecular bonding because of  comparatively  polar nature of molecules . Hence melting point of anhydrous aluminium fluoride is higher than that of anhydrous aluminium chloride .

What is the change that turns paper into ashes ? Why ? give reasons​

Answers

Answer:

Chemical change

Explanation:

Burning  paper is a chemical change.

Burning (or combustion ) is a high temperature chemical reaction that takes place  between fuel and an oxidant(mostly  oxygen)

Research has proved has taught us that ;

When paper is burned , the  oxygen (from the air) combines with carbon and hydrogen in the paper turning some of it into carbon dioxide and water vapor, which waft away with carbon particulates in the smoke

I hope it helps :)

What type of reaction is: ammonium nitrate -> dinitrogen monoxide + water?

Answers

Answer:

The thermal decomposition of ammonium nitrate to produce dinitrogen monoxide and water. This reaction takes place at a temperature of 200-260°C.

If 156.06 g of propane, C3H8, is burned in excess oxygen, how many grams of water are formed? C3H8 + O2 → CO2 + H2O Select one: a. 255.0 b. 765.1 c. 191.3 d. 31.88

Answers

Answer:

The correct option is;

a. 255.0 g

Explanation:

The given information are;

Mass of propane, C₃H₈ in the combustion reaction = 156.06 g

The equation of the combustion reaction is C₃H₈ + 5O₂ → 3CO₂ + 4H₂O

From the balanced chemical equation of the reaction, we have;

One mole of propane, C₃H₈ reacts with five moles oxygen gas, O₂, to form three moles of carbon dioxide, CO₂, and  four moles of water, H₂O

The molar mass of propane gas = 44.1 g/mol

The number of moles, n, of propane gas = Mass of propane gas/(Molar mass of propane gas) = 156.06/44.1 = 3.54 moles

Given that one mole of propane gas produces 4 moles of water molecule (steam) H₂O, 3.54 moles of propane gas will produce 4×3.54 = 14.16 moles of  (steam) H₂O

The mass of one mole of H₂O = 18.01528 g/mol

The mass of 14.16 moles of H₂O = 14.16 × 18.01528 = 255.0 g

The mass of H₂O produced = 255.0 g

If the pH of a weak acid solution is 2.500 and the solution has a concentration of 0.100M, what is the Ka of the weak acid HA?

Answers

Answer:

The Kₐ of the weak acid is 1.033×10⁻⁴

Explanation:

The dissociation of a weak acid in aqueous solution is limited to about 5 to 10%

The acid dissociation reaction is given as follows;

HA (aq) + H₂O (l) → H₃O⁺(aq) + A⁻ (aq)

Given that the pH = 2.5, we have

pH = -log₁₀[H₃O⁺] = 2.5

∴ [H₃O⁺] = 10^(-2.5) = 0.0031623

[tex]K_a = \dfrac{[H_3O^+][A^-]}{[HA]}[/tex]

Kₐ = [H₃O⁺][A⁻]/[HA] = (0.0031623^2)/(0.1 - 0.0031623) = 1.033×10⁻⁴

The acid dissociation constant, Kₐ for weak acid is very low as obtained

You combine 13 g of magnesium with 5 g of nitrogen to form a compound.
What is the mass percent of nitrogen in the compound?

Answers

Answer:

[tex]\large \boxed{28 \, \% }[/tex]

Explanation:

magnesium  + nitrogen ⟶ Product

      13 g                5 g

Mass of product = 13 g + 5 g = 18 g

The product contains 5 g of nitrogen .

[tex]\text{Percent N} = \dfrac{\text{5 g}}{\text{18 g}} \times \, 100\% = \mathbf{28 \, \%}\\\text{The percent by mass of nitrogen is $\large \boxed{\mathbf{28 \, \% }}$}[/tex]

Other Questions
A book has 282 pages,each 0.02mm thick.How thick is the book? 21. Preferred stock pays quarterly dividend of $3 a share. If investors require 12% return on a stock of a similar risk level, what is the price Personality is:_____________. 1. the unpredictable actions of individuals that are typical of most people at least some of the time. 2. a collection of characteristics that defines how a person behaves in different situations. 3. a manner of acting characterized by uniqueness and appeal. 4. the part of a person that is exhibited when in the presence of others. Hey, I need help.A school has 486 students, and this is an 8% increase from the number of students last year. How many students were in school last year?Please also show working out, thanks :) Le ______ t una carta a tu abuela?A. escribisteB. dijiste C. dijoD. escribi hello:)!! for the preparation of salts , I dont really understand the part where acids react with insoluble bases. do I just memorise it? :) thanks! Which character from Achebe Things fall apart is best described as the protagonist foil It is urgent plz answer Anna is saving to buy some souvenirs on a family vacation. She has already saved $125, and she saves another $2 from her allowance every day. Formulate and then graph the equation that models the total amount Anna saves, y, in terms of the number of days she adds to her savings, X. Describe the events by which depolarization of a smooth muscle cell results in contraction and explain why smooth muscle contractions are slow and sustained. a student answered 44 questions correctly on a test with 55 questions. what percent of the test was answered correctly?(plz tell me how to figure it out) The speed at which a ball bits the ground is proportional to theheight to which the ball rebounds. If the ball hits the ground ata speed of 20 miles per hour and rebounds to a height of 10 feet,then how fast must it be traveling (in miles per hour) to reboundto a height of 15 feet? Which of the following is correct about the polyadenylation mechanism? Rewrite the sentences, using verbal phrases in place of the italicized words.I know that I can do better. This knowledge will help me persist. Every day, Jason runs for 34 minutes and lifts weights for 49 minutes. How many minutes will Jason spend working out in 8 days? Help me with this please I have no idea what to do. It says solve for a if the line through the two given points has the given slope a, 3) and (-3, - 1), m = -2 What is the value of $\sqrt{36 \times \sqrt{16}}$? Which option is it?????? Represent the expression(4 x 1,000) + (3 x 100) + (6 x1/100) + (7x1/1000)as a decimal number. Determine the settlement set of the following trigonometric equations! cos (x - 1/3) = cos 1/2, 0 x 2