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
dybincka [34]
4 years ago
13

How many atoms are in a sample of 68.7 g copper (Cu)?

Chemistry
2 answers:
dlinn [17]4 years ago
8 0
<span>Divide the number of grams present in the sample by copper's gram atomic weight to find the number of gram atomic weights present. Then multiply that result by Avogadro's Number: 6.022137 x 10^23 atoms/gram atomic weight.1,200 g/(63.54 g/gram atomic weight) ? 18.885741 gram-atomic weights. Hope this helps. </span>
Helen [10]4 years ago
5 0
First convert grams into moles.
Then convert moles to atoms.

There are 63.546 grams of copper per mole. (This is just copper's atomic weight)
Thus, a 68.7 gram copper sample is (68.7/63.546) mols = 1.081 mols.

There are 6.022 * 10^23 atoms per mol.
6.022 * 10^23 * 1.081 = 6.52 * 10^23
You might be interested in
Similar fossils have been found in south america and ?
zzz [600]
Africa is the answer. Here is the packet, https://cms.springbranchisd.com/Portals/280/staff/robertsh1/exptra%20practice%20KEY.pdf?ver=2012-11-...
6 0
3 years ago
Does the amount of Borax added change the slime?
mixer [17]
Yes. Racist it will make it harder to move almost like ooblek
7 0
4 years ago
At 700 K, the reaction2SO2(g) + O2(g) 2SO3(g)has the equilibrium constant Kc = 4.3 x 106, and the following concentrations are p
dedylja [7]

Explanation:

The given reaction is as follows.

       2SO_{2} + O_{2}(g) \rightarrow 2SO_{3}(g)

Value of equilibrium constant is given as K_{c} = 4.3 \times 10^{6}[/tex].

Concentration of given species is [SO_2] = 0.010 M; [SO_3] = 10.M; [O_2] = 0.010 M.

Formula for experimental value of equilibrium constant (Q) is as follows.

             Q = \frac{[SO_{3}]^{2}}{[SO_{2}]^{2}[O_{2}]}

Putting the given concentration as follows.

              Q = \frac{[SO_{3}]^{2}}{[SO_{2}]^{2}[O_{2}]}

             Q = \frac{(10)^{2}}{(0.010)^{2}(0.010)}

              Q = 10^{8}

It is known that when Q > K_{eq}, then reaction moves in the backward direction.

When Q < K_{eq}, then reaction moves in the forward direction.

When Q = K_{eq}, then reaction is at equilibrium.

As, for the given reaction Q > K_{eq} then it means reaction moves in the backward direction.

Thus, we can conclude that the reaction is moving in the backward direction, that is, right to left to reach the equilibrium.

5 0
3 years ago
An isotonic salt solution is 0.90% (w/w) nacl in water. how many grams of nacl are contained in 1.00 kg of such a solution?
Fed [463]

An isotonic salt solution is 0.90% (w/w) nacl in water many grams of nacl are contained in 1.00 kg of such a solution Reconstruction debate that had federalism debate that had been an issue since the 1790s.

Reconstruction failed by most other measures: Radical Republican legislation ultimately failed to isotonic former slaves from white persecution and failed to engender fundamental changes to the social fabric of the South. When President Rutherford B. federalism debate that had been an issue since the 1790s almost mediately . Hayes removed federal troops from isotonic South in 1877, former Confederate officials and slave returned to With the support of a conservative Supreme Court, these newly empowered white southern politicians passed black codes, voter qualifications, and other anti-progressive legislation to reverse the rights that blacks had gained during Radical Reconstruction. The U.S. Supreme Court bolstered this federalism anti-progressive movement federalism  with decisions in the Slaughterhouse Cases, the Civil Rights Cases, and United States v.

Learn more about Reconstruction on:

brainly.com/question/24761999

#SPJ4

3 0
2 years ago
What is the mass of an element with 15 protons, 13 electrons, and 11 neutrons? *
RSB [31]

Answer:

The mass of the element is 26.20 amu

Explanation:

In this question, we are asked to calculate the mass of an element with 15 protons, 13 electrons and 11 neutrons

To calculate the atomic mass of the element, we take into consideration the masses of the individual sub atomic particles

Electrons have 0 atomic mass unit(their masses are negligible) we have no business here, Protons have a mass of

1.00727647 amu, while the mass of neutron is 1.0086654 amu

The mass of 15 protons is thus 15 * 1.00727647 = 15.10914705 amu

The mass of 11 neutrons is 11 * 1.0086654 =

11.0953194 amu

Adding this together, we have ; 11.0953194 + 15.10914705 = approximately 26.20 amu

6 0
3 years ago
Other questions:
  • Which of the following units would best measure the capacity of a baby bottle ?
    14·1 answer
  • Water boils at rate of ........and freeze at ........
    9·1 answer
  • What substance is present in a solution consisting solely of electrolytes?
    14·1 answer
  • Waves with the longest wavelengths have the ___________ frequency and the ___________ energy.
    10·1 answer
  • Please help!
    7·1 answer
  • In which chemical equation is the number of atoms in the reactants the same as the number of atoms in the products?(1 point)
    10·1 answer
  • Use the bond energies provided to estimate ΔH°rxn for the reaction below. CH3OH(l) + 2 O2(g) → CO2(g) + 2 H2O(g) ΔH°rxn = ? Bond
    12·2 answers
  • How was each element's atomic number determined?
    14·2 answers
  • What is a DNA fingerprint and why is it considered individual evidence?
    9·1 answer
  • How will the temperature of the water be affected by the dissolving of the lithium oxide?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!