1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Nostrana [21]
3 years ago
10

In nature, oxygen has three common isotopes. The atomic masses and relative abundances of these isotopes are given in the table

below.
Isotope Atomic Mass (amu) Relative Abundance
O-16          15.995                          99.759%
O-17          16.995                             0.037%
O-18          17.999                               0.204%
Calculate the average atomic mass of oxygen. Show all of your calculations below.
Chemistry
1 answer:
Reil [10]3 years ago
7 0
<span>15.995* 0.99759 + 16.995*0.00037 + 17.999*0.00204 = 15.999</span>
You might be interested in
Deterioration of buildings, bridges, and other structures through the rusting of iron costs millions of dollars a day. The actua
GrogVix [38]

The value of ∆H when 0.250kg of iron rusts is -1.846 × 10³kJ.

The rust forms when 4.85X10³ kJ of heat is released is 888.916 g.

<h3>Chemical reaction:</h3>

4 Fe + 3O2 ------ 2Fe2O3

∆H = -1.65×10³kJ

A) Given,

mass of iron = 0.250kg = 250 g

<h3>Calculation of number of moles</h3>

moles = given mass/ molar mass

= 250/ 55.85 g/mol.

= 4.476 mol

As we know that,

For the rusting of 4 moles of Fe, ∆H = -1.65×10³kJ

For the rusting of 4.476 moles of Fe ∆H required can be calculated as

-1.65×10³kJ × 4.476 mol/ 4mol

∆H required = -1.846 × 10³kJ

Now,

when 2 mol of Fe2O3 formed, ∆H = - 1.65×10³kJ

It can be said that,

-1.65×10³kJ energy released when 2 mol of Fe2O3 formed

So, -4.6 × 10³kJ energy released when 2 mol of Fe2O3 formed

= 2 × -4.6 × 10³kJ / -1.65×10³kJ

= 5.57 mol of Fe2O3 formed

Now,

mass of Fe2O3 formed = 5.57 mol × 159.59 g/mol

= 888.916 g

Thus, we calculated that the rust forms when 4.85X10³ kJ of heat is released is 888.916 g. and the value of ∆H when 0.250kg of iron rusts is -1.846 × 10³kJ.

learn more about ∆H:

brainly.com/question/24170335

#SPJ4

DISCLAIMER:

The given question is incomplete. Below is the complete question

QUESTION:

Deterioration of buildings, bridges, and other structures through the rusting of iron costs millions of dollars a day. The actual process requires water, but a simplified equation is 4Fe(s) + 3O₂(g) → 2Fe₂O₃(s) ΔH = -1.65×10³kJ

a) What is the ∆H when 0.250kg iron rusts.

(b) How much rust forms when 4.85X10³ kJ of heat is released?

7 0
1 year ago
4. Which atomic particles are found inside the nucleus of an atom?
grin007 [14]

Answer:

the atomic particles in the necluse are called ions which are positive and negive charged atoms

Explanation:

6 0
3 years ago
Why would the presence of oxygen bubbles be a good indicator of photosynthesis occurring?
irina1246 [14]

kdjsbjsof in bwjfiejwnjfifihdhwhbsd

6 0
2 years ago
What was the history and use of the periodic table?
cestrela7 [59]
<span>In 1669 German merchant and amateur alchemist Hennig Brand attempted to created a Philosopher’s Stone; an object that supposedly could turn metals into pure gold. He heated residues from boiled urine, and a liquid dropped out and burst into flames. This was the first discovery of phosphorus.

In 1680 Robert Boyle also discovered phosphorus, and it became public.

In 1809 at least 47 elements were discovered, and scientists began to see patterns in the characteristics.

In 1863 English chemist John Newlands divided the then discovered 56 elements into 11 groups, based on characteristics.

In 1869 Russian chemist Dimitri Mendeleev started the development of the periodic table, arranging chemical elements by atomic mass. He predicted the discovery of other elements, and left spaces open in his periodic table for them.

In 1886 French physicist Antoine Bequerel first discovered radioactivity. Thomson student from New Zealand Ernest Rutherford named three types of radiation; alpha, beta and gamma rays. Marie and Pierre Curie started working on the radiation of uranium and thorium, and subsequently discovered radium and polonium. They discovered that beta particles were negatively charged.

In 1894 Sir William Ramsay and Lord Rayleigh discovered the noble gases, which were added to the periodic table as group 0.In 1897 English physicist J. J. Thomson first discovered electrons; small negatively charged particles in an atom. John Townsend and Robert Millikan determined their exact charge and mass.

In 1900 Bequerel discovered that electrons and beta particles as identified by the Curies are the same thing.

In 1903 Rutherford announced that radioactivity is caused by the breakdown of atoms.

In 1911 Rutherford and German physicist Hans Geiger discovered that electrons orbit the nucleus of an atom.

In 1913 Bohr discovered that electrons move around a nucleus in discrete energy called orbitals. Radiation is emitted during movement from one orbital to another.

In 1914 Rutherford first identified protons in the atomic nucleus. He also transmutated a nitrogen atom into an oxygen atom for the first time. English physicist Henry Moseley provided atomic numbers, based on the number of electrons in an atom, rather than based on atomic mass.

In 1932 James Chadwick first discovered neutrons, and isotopes were identified. This was the complete basis for the periodic table. In that same year Englishman Cockroft and the Irishman Walton first split an atom by bombarding lithium in a particle accelerator, changing it to two helium nuclei.

In 1945 Glenn Seaborg identified lanthanides and actinides (atomic number >92), which are usually placed below the periodic table.</span>
8 0
3 years ago
Helpppppppp plzzzzzz asaaaapppp
9966 [12]

Answer:

Alright, the first thing we have to do is to balance the chemical equation

2Na3N -----> 6Na + 1N2

We have 60g of Na3N, we convert them into moles by dividing the mass of the compound by the molar mass.

Molar mass of Na3N = (22.98 x 3) + (14) = 82.94g/mol

  <u>60</u>          =  0.72341451651 moles of Na3N

82.94

Now because we did the balanced equation, we know the mole to mole ratio of Na3N to N2 would be 2:1, so in order to get the moles of N2 you have to divide the moles of Na3N by 2

0.72341451651 moles/2 = 0.361707258 moles of N2

Now that we have the moles of N2, we just have to determine the mass of it in grams. In order to do that, just multiply the moles by the molar mass of N2 (28g/mol)

0.361707258 x 28 = <u>10.13g of N2</u>

<u>Therefore the decomposition of 60g of Na3N would result in 10.13g of N2 (nitrogen gas)</u>

3 0
2 years ago
Other questions:
  • Which statement most accurately describes the behavior of a catalyst?
    14·1 answer
  • The first element on the periodic table of elements is hydrogen true or false
    5·2 answers
  • How do you predict products?
    12·1 answer
  • A runner wants to run 11.7 km. She knows that her running pace is 6.7 mph. How many minutes must she run?
    10·1 answer
  • Cuántos electrones contiene el átomo de helio​
    15·1 answer
  • What is not the same as 2.97
    6·1 answer
  • Akeem cut his finger during an investigation, and it is bleeding slightly. Before helping him bandage the wound,
    10·2 answers
  • Arrange the colors of visible light, green, red, and blue, in order of increasing wavelength.
    5·1 answer
  • What Will We Do? We will determine if a pen is a system. What function does a pen perform? ​
    9·1 answer
  • Pls help
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!