Which of the following statements best describes the number of neutrons in an atom?
It is the same as the element's atomic number.
It is equal to the sum of atomic number and average atomic mass.
it is the same as the average atomic mass.
it is equal to the difference between atomic number and atomic mass number.

Answers

Answer 1

Answer:

its the last one

Explanation:


Related Questions

A student plans a two-step synthesis of 1-ethyl-3-nitrobenzene from benzene. The first step is nitration of benzene to give nitrobenzene, and the second step is a Friedel-Crafts alkylation using CH3CH2Cl and AlCl3. The plan is flawed because: A : When the alkyl halide interacts with AlCl3, the resulting carbocation can rearrange before it has a chance to react with the aromatic ring. B : Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation. C : The nitro group will direct the incoming alkyl group para position, rather than to the meta position. D : A blocking group is required to achieve this synthesis.

Answers

Answer:

Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation.

Explanation:

The benzene ring in itself does not easily undergo electrophilic substitution reaction. Some groups activate or deactivate the benzene ring towards electrophilic substitution reactions.

-NO2 ia a highly deactivating substituent therefore, Friedel-Crafts alkylation of nitrobenzene does not take place under any conditions.

This reaction scheme is therefore flawed because Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation.

thermal energy is what we call energy that come from ___ of matter

Answers

Temperature is your answer hopefully

what is a 7 letter word that starts with f: Ancient plants and animals formed into rocks.

Answers

Answer:

Fossils?

Explanation:

Use the solubility rules from the Lab 4 introduction and your knowledge of qualitative separation schemes from the lab to answer the following questions. The qualitative analysis experiment you did is actually an abbreviated version of a much larger analysis scheme in which many different cations are separated and identified. Suppose a mixture contains Ag , K , NH4 , Hg22 , Pb2 , Mg2 , Sr2 , Ba2 , Cu2 , Al3 and Fe3 .
(a) Which of the following ions could you separate, by causing them to precipitate, with the addition of HCl?
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+
(b) After the addition of HCl, the above sample is centrifuged and decanted. Which of the following cations remaining in the supernatant could you separate, by causing them to precipitate, with the addition of H2SO4? (Hint: H2SO4 is a source of sulfate ions. Select all that apply.)
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+

Answers

Answer:

a13+a13

Explanation:

An empty steel container is filled with 2.0 atm of H₂ and 1.0 atm of F₂. The system is allowed to reach equilibrium according to the reaction below. If Kp = 0.45 for this reaction, what is the equilibrium partial pressure of HF?

Answers

The equilibrium partial pressure of HF is 0.55 atm.

The equation of the reaction is;

        H2(g) + F2(g) ⇄ 2HF

I         2           1             0

C       -x           -x            +x

E     2 - x        1 - x           x

We know that;

pH2 = 2.0 atm

PF2 =  1.0 atm

pHF = ??

Kp = 0.45

So;

Kp = (pHF)^2/pH2. pF2

0.45 = x^2/(2 - x) (1 - x)

0.45 =  x^2/x^2 - 3x + 2

0.45(x^2 - 3x + 2) = x^2

0.45x^2 - 1.35x + 0.9 =  x^2

0.55 x^2 + 1.35x - 0.9 = 0

x = 0.55 atm

Learn more about equilibrium: https://brainly.com/question/3980297

A certain protein transports a sodium ion from the inside of the cell membrane to the outside using active transport. Which of the following must be true? A. There is no change in concentration before or after transport. B. The transport process did not use chemical energy. C. After transport, the concentration of protein in the cell decreases. D. After transport, the concentration of sodium is lower inside the cell.

Answers

D is the answer because all the sodium will lower the cells inside due to the membrane using active transport

how many moles of nitrogen gas are produced in the reaction if we started with 6 moles of ammonium nitrate

Answers

9moIN2 :
The molar ratio between Nitrogen and ammonia is
1
:
3
, therefore, to produce 18 moles of ammonia, we will need

Calculate the pH of each of the following aqueous solutions. (Enter your answers to two decimal places.) (a) 10.0 mL deionized water WebAssign will check your answer for the correct number of significant figures. 2.72 Incorrect: Your answer is incorrect. (b) 10.0 mL deionized water plus 5.0 mL of 0.10 M NaOH WebAssign will check your answer for the correct number of significant figures. (c) 10.0 mL deionized water plus 10.0 mL of 0.10 M NaOH WebAssign will check your answer for the correct number of significant figures. (d) 10.0 mL deionized water plus 15.0 mL of 0.10 M NaOH WebAssign will check your answer for the correct number of significant figures.

Answers

Answer:

a. pH = 7.0

b. pH = 12.52

c. pH = 12.70

d. pH = 12.78

Explanation:

a. Deionized water has the [H⁺] of pure water = 1x10⁻⁷ (Kw = 1x10⁻¹⁴ = [H⁺][OH⁻] - [H⁺] = [OH⁻ -)

pH = -log[H⁺] = 7

b. Moles NaOH = 5x10⁻³L * (0.10mol / L) = 5x10⁻⁴moles OH⁻ / 0.015L = 0.0333M = [OH⁻]

-Total volume = 10mL+5mL = 15mL = 0.015L

pOH = -log[OH⁻] = 1.48

pH = 14-pOH

pH = 12.52

c. Moles NaOH = 0.010L * (0.10mol / L) = 1x10⁻³moles OH⁻ / 0.020L = 0.0500M = [OH⁻]

-Total volume = 10mL+10mL = 20mL = 0.020L

pOH = -log[OH⁻] = 1.30

pH = 14-pOH

pH = 12.70

d. Moles NaOH = 0.015L * (0.10mol / L) = 1.5x10⁻³moles OH⁻ / 0.025L = 0.060M = [OH⁻]

-Total volume = 10mL+15mL = 25mL = 0.025L

pOH = -log[OH⁻] = 1.22

pH = 14-pOH

pH = 12.78

number of molecules in lithium sulfate Li2So4​

Answers

What the question there is nun

If you began a reaction with the following ions in solution, what would be the net ionic equation?
Na+, PO43–, Fe2+, and NO3–

Answers

Answer:

2 PO₄³⁻(aq) + 3 Fe²⁺(aq) ⇒ Fe₃(PO₄)₂

Explanation:

Let's consider the complete ionic equation between the ions present. It includes all the ions and the insoluble compounds (Fe₃(PO₄)₂ is insoluble).

Na⁺(aq) + 2 PO₄³⁻(aq) + 3 Fe²⁺(aq) + NO₃⁻(aq) ⇒ Fe₃(PO₄)₂ + Na⁺(aq) + NO₃⁻(aq)

The net ionic equation includes only the ions that participate in the reaction (not spectator ions) and the insoluble compounds.

2 PO₄³⁻(aq) + 3 Fe²⁺(aq) ⇒ Fe₃(PO₄)₂

PLEASE HELP IMMEDIATE WORTH 10 POINTS

Fill in the blank with the word or phrase that best completes the statement or answers the question. The scientific name for a plant that reproduces with flowers is a(n)​

Answers

Answer:

the scientific name is Angiosperms

Explanation:

please mark brainliest

Lithium and nitrogen react to produce lithium nitride:
6Li (s) + N2 (g) = 2Li3N (s)
How many moles of lithium nitride are produced when 0.400 mol lithium are used in this reaction?
a. 1.28 mol
b. 0.133 mol
c. 0.800 mol
d. 0.0667 mol

Answers

Answer:

B : 0.133 M

Explanation:

moles Li3N3 = 0.4 mol Li x (2 moles Li3N/6 moles Li) = 0.133 M

How many grams equal 4.3 x 1024 atoms of oxygen (02)?

Answers

Answer: 248.66g

Explanation:

4.3e24 / 6.23e23 = 6.9 mols O2

6.9(18.02*2)=248.66

What is 6.25 in scientific notation?

Answers

It is 6.25x10^0 I believe :)
I think it’s 6.25 x 10^2

Hydrogen has an oxidation number of +1 in all compounds excepts when it binds with metals and has an oxidation state of -1.​

Answers

Answer:

See explanation

Explanation:

In the periodic table, hydrogen is placed in group 1 for convenience. Hydrogen is not a metal, however, its common oxidation state is +1. It easily forms a univalent positive ion just like group 1 elements.

So, when hydrogen is combined with strongly electropositive metals such as sodium, lithium, etc, hydrogen accepts one electron and exhibits an oxidation state of -1 in those compounds.

Such compounds in which hydrogen is combined with strongly electropositive metals to give a binary compound is called a hydride.

adaptive features of aquatic plants​

Answers

Aquatic plants can only grow in water or in soil that is frequently saturated with water. They have leaves with large air pockets allowing them to absorb oxygen from the water (they should have one air bubble in each leaf). The leaves of aquatic plants are soft. It allows them to move smoothly/easily with the waves.

CAN SOMEONE PLEASE HELP ME I WILL MARK AS BRAINLIEST :(

Answers

Answer:

ok so i did the problem and the answer was 8e+29

Explanation:

i dont really know what the answer is but thats the answer i got

sorry if this didnt help

Please someone help me with this!!

Answers

You’re answer would be A, when you open a parachute it captures air and shoots you upwards for a couple seconds because of how fast it slows the weight down.

What is produced when concentrated aqueous sodium chloride is electrolysed?

Answers

When an electric current is passed through concentrated sodium chloride solution, hydrogen gas forms at the negative electrode , chlorine gas forms at the positive electrode, and a solution of sodium hydroxide also forms. You might have expected sodium metal to be deposited at the negative electrode.

You’re welcome!! Have a good day/night :)

what is the structure of methane​

Answers

Answer:

CH4

Explanation:

if it is wrong, i blame my brain

hi, if your looking for extra points (50+) and br ainiest here is ur chance, answer this question correctly plz

Answers

C! the others don’t make sense

Copper has a specific heat of 0,900 J(g C). How much energy in kJ is needed to raise the temperature of a 700 g block of aluminum from 30.7°C to 82,1C?(show your steps)

Answers

Answer:

32.4 kJ

Explanation:

Given that:

Specific heat capacity fo copper, c = 0.9

Mass of copper, m = 700 g

Temperature change, dθ ;t2 - t1 = (82.1 - 30.7) = 51.4

Energy required, E = mcdθ

E = 700 * 0.9 * 51.4

E = 32382 J

Energy required on kJ

32382 / 1000

= 32.382 kJ

= 32.4 kJ

Do you think humans are responsible for global warming trends? Why or why not?

Answers

Answer:

Yes. At least some. There has been ups and downs in temperature ever since the Earth was created, and this is just another up in temperature. I do think that humans have made it worse though, with all of the greenhouse gases and things like that.

Whoever gets these 2 right gets brainliest! :)

Answers

the first one is A covalent bond.

the second one is Answer: B Decomposition

The human body can get energy by metabolizing proteins, carbohydrates or fatty acids, depending on the circumstances. Roughly speaking, the energy it gets comes mostly from allowing all the carbon atoms in the food molecules to become oxidized to carbon dioxide CO2 by reaction with oxygen from the atmosphere. Hence the energy content of food is roughly proportional to the carbon content.
Let's consider alanine, C3H7NO2, one of the amino acids from which proteins are made, and glucose C6H12O6, one of the simplest carbohydrates. Using the idea above about energy content, calculate the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose.

Answers

Answer:

the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose is 1.0111

Explanation:

Given the data in the question;

To determine the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose, first we get the molar masses of both alanine and glucose

we know that;

Molar mass of alanine ( C₃H₇NO₂ ) = 89.09 g/mol

Molar mass of glucose ( C₆H₁₂O₆ ) = 180.16 g/mol

now, { metabolizing each gram }

moles of alanine = mass taken / molar mass

= 1g / 89.09 g/mol = 1/89.09 moles

moles of glucose = mass taken / molar mass

= 1g / 180.16 g/mol = 1/180.16 moles

In each molecule of alanine, we have 3 atoms  of carbon.

Also, in each molecules of glucose, we have 6 atoms of carbon

so,

number of moles of Carbons in alanine = 3 × 1/89.09 moles = 0.03367

number of moles of Carbons in glucose = 6 × 1/180.16 moles = 0.0333

so ratio of energy will be the ratio of carbon atoms, which is;

⇒ 0.03367 / 0.0333 = 1.0111

Therefore, the ratio of the energy the body gets metabolizing each gram of alanine to the energy the body gets metabolizing each gram of glucose is 1.0111

Suppose an EPA chemist tests a 250.mL sample of groundwater known to be contaminated with nickel(II) chloride, which would react with silver nitrate solution like this: NiCl2(aq) + 2AgNO3(aq) → 2AgCl(s) + NiNO32(aq) The chemist adds 15.0mM silver nitrate solution to the sample until silver chloride stops forming. He then washes, dries, and weighs the precipitate. He finds he has collected 5.8mg of silver chloride. Calculate the concentration of nickel(II) chloride contaminant in the original groundwater sample. Round your answer to 2 significant digits.

Answers

Answer:

0.0010 w/v %

Explanation:

Based on the reaction:

NiCl₂(aq) + 2AgNO₃(aq) → 2AgCl(s) + Ni(NO₃)₂(aq)

Finding the moles of AgCl produced we can find the moles of NiCl in the reaction medium and its mass:

Moles AgCl -Molar mass: 143.32g/mol-:

5.8mg = 5.8x10⁻³g * (1mol / 143.32g) = 4.047x10⁻⁵ moles AgCl

Moles NiCl₂:

4.047x10⁻⁵ moles AgCl * (1mol NiCl₂ / 2mol AgCl) = 2.023x10⁻⁵ moles NiCl₂

Mass NiCl₂ -Molar mass: 129.60g/mol-:

2.023x10⁻⁵ moles NiCl₂ * (129.60g / mol) = 2.62x10⁻³g of NiCl₂ are produced.

And the concentration in w/v% is:

2.62x10⁻³g NiCl₂ / 250mL * 100 =

0.0010 w/v %

At what minimum temperature do rocks melt into lava?
A) 3,500 degrees Celsius
B) 6,332 degrees Fahrenheit
C) 800 degrees Fahrenheit
OD 800 degrees Celsius

Answers

The answer is D 800 degrees Celsius

How many atoms are in 90.43 moles of copper

Answers

409 g P2O5 2) 5.44 x 1025 atoms Cu

Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 8.12×10²³ atoms are in  90.43 mole of copper.

What is mole?

The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity of amount of substance. It measure the number of elementary entities of a given substance that are present in a given sample. There are so many formula for calculating mole.

we know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number

number of atoms/molecules=number of moles × 6.022×10²³(Avogadro number)

number of moles of copper=90.43 moles

Substituting all the given values in the above equation, we get

number of atoms/molecules= 90.43 × 6.022×10²³

number of atoms/molecules=8.12×10²³ molecules

Therefore, 8.12×10²³ atoms are in 90.43 mole of copper.

To know more about mole, here:

https://brainly.com/question/15209553

#SPJ2

Fill in the blanks. 3NH3

Answers

Answer:

3, 9, 3

Explanation:

The coefficient of 3 tells us that there are three molecules (the chemical unit of NH3). Each molecule of ammonia (NH3) is made up of 1 atom of nitrogen bonded to 3 atoms of hydrogen.

Since there are three molecules, we have three times the amount of atoms there are in one molecule.

3 x 1 = 3 nitrogen

3 x 3 = 9 hydrogen

What enzyme catalyses the reaction of PRPP transfer to hypoxanthine with
formation of IMP?

Answers

Answer:

HPRT

Explanation:

HPRT catalyzes the salvage reactions of hypoxanthine and guanine with PRPP to form IMP and GMP

The formation of GMP from IMP requires oxidation at C-2 of the purine ring, followed by a glutamine-dependent amidotransferase reaction that replaces the oxygen on C-2 with an amino group to yield 2-amino,6-oxy purine nucleoside monophosphate, or as this compound is commonly known, guanosine monophosphate.

Other Questions
A tank is is half full of oil that has a density of 900 kg/m3. Find the work W required to pump the oil out of the spout. (Use 9.8 m/s2 for g. Assume r = 15 m and h = 5 m.) W = 1.59 J please help ASAP!!!!40 points!!!!!!!!No fake answers!!!!!!!!!!!!need ALL answers ASAP!!!!!!!!!!!!please please please don't waste my points!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! k.Bill refuses to eat peas, _ _____ will he touch carrots. Don't waste my points!! Don't Answer Unless %100 PositiveWhich two choices were the effects of Neo-Confucianism on China during the Middle Ages?A.It led to the decline of agricultural practices.B.It gave rise to a new social class.C.It made people more financially secure.D.It helped with the selection of able government officials.E.It caused an increase in artistic publications. How does an increase in thermal energy affect the kinetic energy of the particles in each state of matter Which strategies are helpful for maintaining a healthy body temperature when exercising in hot weather?(Select all that apply.)drink 6-10 ounces of water for every 60 minutes of physical activitypaying attention to warning signs of overheating, such as leg cramps and headachearranging to work out early in the morning or evening to avoid the day's hottest time periodsdrink 6-10 ounces of an energy drink for every 45 minutes of physical activity. PLEASE HELP ILL GIVE BRAINLIEST FOR BEST ANSWER!!Palindrome numbers are numbers that read the same forward or backward. here are some palindrome numbers: 11, 121, 75257, and 1234321. The smallest three digit palindrome is 101. How many palindrome numbers are there between 10 to 1000? a square has a side length of (x-7) a what is the area? A package of 4 pair of insulated socks cost $32.76. What is the unit price of the pair of socks Caroline delivers flowers and earns $1.25 for each rose and $0.75 for each daisy. What is her total pay for a week in which she sold 288 roses and 432 daisies? March is National Women's Appreciation Month! I want you to think about a woman - whether a member of family, celebrity, person of importance - who you admire and look up to.Write 3-5 sentences about how that woman influenced you and why you feel they deserve recognition Can the table below represent values of a function? explain why. The Clinton Riot resulted from?an effort by federal troops to stop KKK activities. an effort by white supremacists to disrupt a Republican rally. an attempt by armed citizens to remove officials from office. an attack on a Democratic rally by armed African Americans. Which is a characteristic of Greek myths? A. The hero is perfect. B. The hero has a flaw. C. The characters are only humans. D. The characters are only gods. Who can help me with this question problem 1. The urban centres of the Harappan civilization developed from which millennium BCE. What is the effect of inputting stem cells instead of body cells into the original system? Mark all that apply. What purposes does Phi-oo serve in the novel?He translates for Mr. Cavor.He acts as Mr. Cavors guide.He is Mr. Cavors foe.He protects Mr. Cavor. Question 3: Mettez au pluriel1. Le livre2. La chaise Graph f(x)=|x+1|+2. Shows vertex and 4 points.