What is the mass number of an element?
A. Mass number is the number of protons in the nucleus.
B. Mass number is the mass of the protons in the nucleus.
C. Mass number is the mass of the most abundant isotope.
D. Mass number is the atomic mass of a particular isotope.

Answers

Answer 1

The mass number of an element is the sum of the protons and neutrons present in the nucleus of the atoms of the element.

What is mass number?

The mass number of an element is the number obtained when the number of protons and neutrons in the nucleus of an atom of the element are summed together.

The sum of protons and neutrons in the nucleus of an atom is collectively known as the nucleon. Thus, the mass number of an atom can also be referred to as the nucleon of the atom.

This can be mathematically expressed as:

Mass number = number of protons + number of neutrons.

Atoms generally contain protons, neutrons, and electrons. The protons are positively charged and are located in the nucleus, the neutrons are also located in the neucleus but have no charges. The electrons, on the other hand, are located outside the nucleus in regions referred to as orbitals.

The sum of the protons and neutrons determine the mass of an atom because the contribution of electrons to the mass of atoms is negligible.

Thus, the mass number of an element is the sum of proton and neutron numbers present in the nucleus of the atoms of the element.

More on mass number can be found here: https://brainly.com/question/4408975

#SPJ1


Related Questions

Why does sodium chloride form a crystal lattice

Answers

Answer:

Ions of opposite charge strongly attract each other; those of like charges repel. As a result ions in an ionic compound are arranged in a particular manner.

Explanation:

Google is smart

help pls
Which process of sedimentary rock formation occurs last?

cementation
compaction
deposition
erosion

Answers

Erosion is the answer

Answer:

Compaction.

Explanation:

All the others are before this.

When 2.16g of H2 reacts with excess O2 by the following equation, 258 kJ of heat are released. What is the change of enthalpy associated with the reaction of 1.00 mol of hydrogen gas? 2H2+O2⟶2H2O

Answers

Answer:

-241 kJ/mol

Explanation:

Let's consider the reaction of hydrogen with excess oxygen to form water.

2 H₂ + O₂ ⟶ 2 H₂O

When 2.16g of hydrogen reacts with excess oxygen, 258 kJ of heat are released, that is, Q = -258 kJ. Considering that the molar mass of hydrogen is 2.02 g/mol, the change of enthalpy associated with the reaction of 1.00 mol of hydrogen gas is:

ΔH° = -258 kJ/2.16 g × (2.02 g/1.00 mol) = -241 kJ/mol

Solid diarsenic trioxide reacts with fluorine gas (F2) to produce liquid arsenic pentafluoride and oxygen gas (O2). Write the Qc for this reaction.

Answers

Answer:

QC= [O2]^3/[F2]^10

Explanation:

Green light has a wavelength of 510 nm. What is the wavelength in meters?

Answers

5.1 × 10^-7 meter........................

PLEASE HELP! WILL DO BRAINLIEST! What do scientists call all of the compounds that contain carbon and are found in living things?
organic

inorganic

acidic

nonacidic

Answers

Answer:

acidic because of electrical issues and the body of electrical equipment

What is the most highly populated rotational level of Cl2 (i) 25deg C and (ii) 100 deg C? Take B=0.244cm-1.This question should not be resubmitted, it is a textbook question from the Atkins physical chemistry txtbook. 10 e.

Answers

Answer:

i

[tex]J_{m} = 20 [/tex]

ii

[tex]J_{m} = 22.5 [/tex]

Explanation:

From the question we are told that

  The first temperatures is [tex]T_1 =  25^oC =  25 +273 =298 \ K[/tex]

   The second temperature is  [tex]T_2 =  100^oC =  100 +273 = 373 \ K[/tex]

Generally the equation for  the most highly populated rotational energy level is mathematically represented as

     [tex]J_{m} = [ \frac{RT}{2B}]  ^{\frac{1}{2} } - \frac{1}{2}[/tex]

Here R is the gas constant with value [tex]R =8.314 \ J\cdot K^{-1} \cdot mol^{-1}[/tex]

Also  

      B is given as [tex]B=\ 0.244 \ cm^{-1}[/tex]

   Generally the energy require per mole to move 1 cm is  12 J /mole

So   [tex]0.244 \ cm^{-1}[/tex]  will require x J/mole

           [tex]x =  0.244 *  12[/tex]

=>          [tex]x =  2.928 \ J/mol [/tex]

So at the first temperature

     [tex]J_{m} = [ \frac{8.314 * 298  }{2*  2.928 }]  ^{\frac{1}{2} } - 0.5 [/tex]

=>  [tex]J_{m} = 20 [/tex]

So at the second temperature

           [tex]J_{m} = [ \frac{8.314 * 373  }{2*  2.928 }]  ^{\frac{1}{2} } - 0.5 [/tex]

=>  [tex]J_{m} = 22.5 [/tex]

In the laboratory you dissolve 18.7 g of copper(II) bromide in a volumetric flask and add water to a total volume of 375mL.

Required:
a. What is the molarity of the solution?
b. What is the concentration of the copper(II) cation?
c. What is the concentration of the acetate anion?

Answers

Answer:

a) - 0.2 M

b) - 0.2 M

c)- 0

Explanation:

The chemical formula of copper (II) bromide is CuBr₂. Its molar mass (MM) is calculated as follows:

MM(CuBr₂)= MM(Cu) + (2 x MM(Br) = 63.5 g/mol + (2 x 80 g/mol)= 223.5 g/mol

a). Molarity = moles CuBr₂/1 L solution

moles CuBr₂ = mass/MM = 18.7 g x 1 mol/223.5 g = 0.084 mol

Volume in L = 375 mL x 1 L/1000 mL = 0.375 L

M = 0.084 mol/(0.375 L) = 0.223 M ≅ 0.2 M

b). When is added to water, CuBr₂ dissociates into ions as follows:

CuBr₂ ⇒ Cu²⁺ + 2 Br⁻

We have 1 mol Cu²⁺ (copper (II) cation) per mol of CuBr₂. Thus, the concentration of copper (II) cation is:

0.2 mol CuBr₂ x 1 mol Cu²⁺/mol CuBr₂ = 0.2 M

c). The concentration of acetate anion is 0. There is no acetate anion in the solution (the anion from CuBr₂ is bromide Br⁻).

Which statements about mixture is FALSE?
A. The ingredients ofvthe mixture keep their physical properties
B. Mixture components can be separated
C. All mixtures are food or drink only
D. A mixture contains more than one ingredients

Answers

It’s b I took the test

If 25.98 mL of 0.1180 M KOH reacts with 52.50 mL of CH3COOH solution, what is the molarity of the acid solution?

Answers

Answer:

Explanation:

We shall use the formula S₁V₁ = S₂V₂

S₁ = .1180 M , V₁ = 25.98 mL

S₂ = ? , V₂ = 52.50 mL

.1180 M  x 25.98 = 52.50 x S₂

S₂ = .0584 M

Molarity of the acid solution = .0584 M .

The concentration of the acid solution is 0.058 M.

The equation of the reaction is;

CH3COOH(aq) + KOH(aq) ----->  CH3COOK(aq) + H2O(l)

The following are known;

Concentration of base CB = 0.1180 M

Volume of base VB =  25.98 mL

Concentration of acid CA = ?

Volume of acid VA = 52.50 mL

Number of moles of acid NA = 1

Number of moles of base NB = 1

Using;

CAVA/CBVB =NA/NB

CAVANB = CBVBNA

CA=  CBVBNA/VANB

CA = 0.1180 M × 25.98 mL × 1/52.50 mL × 1

CA = 0.058 M

Learn more: https://brainly.com/question/24381583

Which of the items below is a colloid?
a.fruit salad b.gelatin c.lacquer​

Answers

Answer:

b. gelatin

Explanation:

a homogeneous noncrystalline consisting of large molecules or ultramicroscopic particles of one substance.

Which of the following best describes the structure of a nucleic acid?


a. Carbon ring(s)
b. Globular or fibrous
c. Single or double helix
d. Hydrocarbon(s)

Answers

It’s A. Carbon Rings

Fluorine is the first element in Group 17 of the periodic table. Bromine is the third element in the same group. Which statement is true of both
elements?
A. Both of their ions will have the same positive charge.
B. The charge on the ion formed by fluorine will be less than the charge on the bromine ion.
C. The charge on the ion formed by fluorine will be greater than the charge on the ion formed by bromine.
D. Both of their ions will have the same negative charge.

Answers

Answer:D. Both of their ions will have the same negative charge

Explanation:

It is D both of their ions will have the same negative charge

What is the pH of a solution made by mixing 0.050 mol of NaCN with enough water to make a liter of solution

Answers

Answer:

pH = 11

Explanation:

The equilibrium of a weak base as NaCN in water is:

NaCN(aq) + H₂O(l) ⇄ OH⁻(aq) + Na⁺(aq) + HCN(aq)

And kb, the equilibrium constant, is:

Kb = [OH⁻] [HCN] / [NaCN]

Where Kb of NaCN is 2.04x10⁻⁵

In the beginning, the [NaCN] is 0.050mol / L = 0.050M.

Both [OH⁻] and [HCN] are produced from this equilibrium, and its concentration is X, that is:

2.04x10⁻⁵ = [X] [X] / [0.050M]

1.02x10⁻⁶ = X²

X = 1x10⁻³ = [OH⁻]

As pOH = - log [OH⁻]

pOH = 3.00

And pH = 14 - pOH

pH = 11

pencil has a density of 14.5 g/mL and a volume of 5 mL. Calculate the mass in grams.

Answers

Answer:

The answer is 72.5 g

Explanation:

The mass of a substance when given the density and volume can be found by using the formula

mass = Density × volume

From the question we have

mass = 14.5 × 5

We have the final answer as

72.5 g

Hope this helps you

What two types of elements make up an Ionic bond ?

Answers

Answer:

Metals and Non-metals

Explanation:

Which set of procedures would be best to follow when separating a mixture of sand, salt, and water?

Answers

Answer:

Pour the mixture through a filter to separate the sand, then evaporate the liquid to separate the salt.

Explanation:

There are various methods used to separate single substances from a mixture. The method adopted depends upon the type of mixture and the ingredients used in it. According to the given question, the mixture comprises of sand, salt and water. Here, the first process will be the process of filtration. Through filtration, the salt-water solution and sand can be separated. Salt-water solution can be separated by the process of evaporation in which sat and water will be separated individually.

what element has a higher ionization energy carbon or silicon

Answers

Carbon has the highest ionization energy
Carbon has the highest ionization energy in the group. The ionization energy for silicon is lower because the outermost electrons for silicon (3p) are further away from the nucleus than those of the 2p level for carbon.

When you finish exercising, you are hot, tired, and sweating. After a bottle of juice, you feel a lot better. Which organ systems are working together in this scenario?

Answers

Answer:

Nervous and Excretory

Explanation:

The nervous system makes you thirsty. The integumentary system makes you sweat. the integumentary system is very similar to the Excretory system.

Nervous and Excretory systems are working together in this scenario.

The nervous system makes you thirsty. The integumentary system makes you sweat. the integumentary system is very similar to the Excretory system.

The blood flow increases, your brain is exposed to more oxygen and nutrients. Exercise also induces the release of beneficial proteins in the brain. Sweating cools the body when it becomes warm. When the body temperature rises, such as when exercising on a hot day, the dermal blood vessels dilate.The excretory system works with the endocrine system to help maintain homeostasis.

Learn more:

brainly.com/question/17342396

How long would it take a bus traveling 52 km/h to travel 130 km

Answers

Answer:

2 and a half hours

Explanation:

Time is equal to distance over speed

9th grade science need help ASAP

Answers

Answer:

D

Explanation:

It is a solid everything that is a solid is heavier

a. Describe the molecule chlorine dioxide, CIO in terms of three possible resonance structures.
b. Do any of these resonance structures satisfy the octet rule for every atom in the molecule? Why or why not?

Answers

Answer:

See explanation

Explanation:

The compound ClO2 has 19 valence electrons.  ClO2 is a bent molecule with tetrahedral electron pair geometry but has two  lone pairs of electrons. This is indicated by the presence of four electron pairs on the outermost shell of the central atom.

The molecule has an odd number of valence electrons, hence, it is generally regarded as a paramagnetic radical. None of the proposed Lewis structures for the molecule is satisfactory because none of them obeys the octet rule.

From the images attached, one can easily see that the electron dots around the oxygen and chlorine atoms does not satisfy the octet rule in all the resonance structures shown.

If the earth was a guava fruit, the space where the seeds are would be the core/mantle​

Answers

Right on ! I need to answer a question to get mine answered so here I am :)

Please help I need to turn this in already

Answers

Answer:

The acceleration will be .5 and the force will be 37.5

Have a nice day!   :)

Answer:

Hello. The answer is 37.5N.

Explanation:

If you look carfully ، every time that you add one weight the force changes 2.5N so you can do this:

[tex](2.5 \times 5) + 25 = 37.5[/tex]

If you collect 5.74 mL of O 2 at 298 K and 1.00 atm over 60.0 seconds from a reaction solution of 5.08 mL, what is the initial rate of the reaction

Answers

Answer:

7.71 × 10⁻⁴ M/s

Explanation:

The initial rate of the reaction can be expressed by using the formula:

[tex]\dfrac{\Delta [O_2]}{\Delta t}[/tex]

where the number of moles of O₂ = [tex]\dfrac{PV}{RT}[/tex]

where;

Pressue P = 1.00 atm

Volume V =5.74mL =  (5.74 /1000) L

Rate R = 0.082 L atm/mol.K

Temperature = 298 K

[tex]= \dfrac{1.00 \ atm \times \dfrac{5.74 }{1000}L}{0.082 \ L \ atm/mol.K \times 298 K}[/tex]

= 2.35 × 10⁻⁴ mol

Δ[O₂] = [tex]\dfrac{moles \ produced - initial \ mole}{\dfrac{5.08 }{1000}L }[/tex]

Δ[O₂] = [tex]\dfrac{2.35 \times 10^{-4} M - 0 M}{\dfrac{5.08 }{1000}}[/tex]

Δ[O₂]  = 0.04626 M

The initial rate = [tex]\dfrac{\Delta [O_2]}{\Delta t}[/tex]

= [tex]\dfrac{0.04626}{60}[/tex]

= 7.71 × 10⁻⁴ M/s

Which of the following elements has the largest atomic radius? Bromine, Barium, Magnsium, Zinc

Answers

Answer:

Atomic radii vary in a predictable way across the periodic table. As can be seen in the figures below, the atomic radius increases from top to bottom in a group, and decreases from left to right across a period. Thus, helium is the smallest element, and francium is the largest.

Explanation:

2) (3 pts) Convert 85 oF to oC.

Answers

Answer:

The answer will be 29.4˚C.

Explanation:

Using the formula 5(˚F-32)/9, plug in the numbers and you'll get 29.4˚C.

A piece of metal has a mass of 0.650 kilograms, has a width of 0.136 meters, and has a length of 0.0451 meters.Part A: If the metal’s volume is 291 cm3, what is the height of the metal in centimeters? (The width & length values given above are in a different unit!)

Part B: What is the density of this piece of metal?

Answers

Answer:

height = 4.74 cm

density = 2.23 g/ cm³

Explanation:

Mass of metal = 0.650 kg (650 g)

Width = 0.136 m    

Length = 0.0451 m  

Volume of metal = 291 cm³

Height in cm = ?

density of metal =?

Solution:

Width = 0.136 m    (0.136 m×100 cm/1m = 13.6 cm)

Length = 0.0451 m  (0.0451 m×100 cm/1m = 4.51 cm)

First of all we will calculate the height:

Volume = height× width× length

291 cm³ =      h     × 13.6 cm × 4.51 cm

291 cm³ =      h     × 61.34 cm²

h = 291 cm³ / 61.34 cm²

h = 4.74 cm

Density:

d = m/v

d = 650 g/291 cm³

d = 2.23 g/ cm³

Which element will gain three electrons to form an anion?
A. aluminum
B. chromium
C. iron
D. nitrogen

Answers

Answer:

D represents the element nitrogen which will gain three valence electrons forming a 3 ion.

Answer:

answer is

Explanation:

D

which material should you use so that the area is cool in terms of temperture O asphalt O red bricks O concrete O soil O

Answers

Answer:

red bricks

Explanation:

right on edg 2020

Red bricks should you use so that the area is cool in terms of temperture. Therefore, option B is correct.

What are red bricks used for?

Red bricks can be used in the construction of structures such as buildings, foundations, arches, pavement, and bridges. These can also be used for aesthetic purposes such as landscaping, face work, and a variety of other architectural purposes.

Traditional red bricks are saw to be more robust, and structures constructed with them are stronger than hollow block structures.Red brick can be warm, with rust or terracotta undertones. They could also be cool and more burgundy.

Thus, Red bricks should you use so that the area is cool in terms of temperture, option B is correct.

To learn more about the red bricks, follow the link;

https://brainly.com/question/14893671

#SPJ6

Other Questions
10. (02.01 MC)Read the sentence:Today, Mandy needs to carefully transplant her tomato seedlings from their pot to their place in the garden,Using context clues, what is the meaning of the word transplant? (2 points)To give special care to a dying plantTo feed a plant a vitamin-rich dietTo trim extra leaves off of a young plantTo change where a plant is growing compare and contrast mexico and the caribbean islands. Into which two smaller groups are plants divided.(a)vascular and nonvascular (b)seed and seedless(c)monocots and dicots(d)seeds and spores giving 17 points please help he Production Department of Hruska Corporation has submitted the following forecast of units to be produced by quarter for the upcoming fiscal year: 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter Units to be produced 11,900 10,900 12,900 13,900 Each unit requires 0.20 direct labor-hours and direct laborers are paid $15.00 per hour. In addition, the variable manufacturing overhead rate is $1.50 per direct labor-hour. The fixed manufacturing overhead is $99,000 per quarter. The only noncash element of manufacturing overhead is depreciation, which is $39,000 per quarter. Required: 1. Calculate the companys total estimated direct labor cost for each quarter of the the upcoming fiscal year and for the year as a whole. 2&3. Calculate the companys total estimated manufacturing overhead cost and the cash disbursements for manufacturing overhead for each quarter of the upcoming fiscal year and for the year as a whole. In one full day, a kudzu vine can grow 15 inches in length. How many inches per hour is this? What is the value of x? Enter only the number in the box! Help Asap 1 poil2. A person who reflects as a trait is one who develops andmaintains impressions of confidence and responsibility. *A. ToleranceB. IntegrityC. CaringD. TrustworthinessE. Respect thermal energy transfer by conduction happens when heat moves from one object to another by Who negotiated a treaty to resolve the continuing problems with the British?Vice President John AdamsSecretary of State Thomas JeffersonChief Justice John JaySecretary of the Treasury Alexander Hamilton Question 61 ptsIf f(x) = 0.41x is a function that represents the cost to mailx number of letters, what is a reasonable domain for f?O all real numberso all real numbers greater than 0O the set of all whole numberso the set of all integers name every my hero acadamia character What did the French establish in the Americas? A. fishing and fur trade B. gold and silver mines C. new communities D. slave trade Find the slope of the line When people or animals travel from one place to the next, it is called what? Which statement best represents the US response to the September 11 attack? A)the Bush Administration launched operation enduring freedom in Afghanistan in the war in Iraq to remove Saddam Hussein B)the Clinton Administration launched the global war on terror to remove the various terrorist organizations. C)the Obama Administration signs the joint comprehensive plan of action to Limited Irans nuclear programsD) the Trump Administration loosened trade restrictions on North Korea to Foster political relations When solving for x, the sine of 33 is used. What other angle and trigonometric function could be used to solve for x? a. cos 57 c. tan 57 b. tan 33 d. cos 33hurry why might china's governmental system be the first truly merit based bureaucracy This is an opinion based question so plz don't delete i would actually like to know what people think.Most of the math we learn in school do you actually think that we use half of it?Also tell me how to give brainliest in your answer so I can give full pointsplease actually answer the question this is worth 50 points and i dont want to waste them What does this diagram represent? Which property of minerals is the least reliable for identifying minerals?hardnesslusterstreakcolor