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
just olya [345]
3 years ago
8

An element has two naturally occurring isotopes, X-85 with a mass of 84.9118 amu and a natural abundance of 72.17%, and X-87 wit

h a mass of 86.9092 amu and a natural abundance of 27.83%. Calculate the atomic mass of this element.
Chemistry
1 answer:
QveST [7]3 years ago
5 0

Answer:

This element is Rubidium (Rb) and has an average atomic mass of 85.468 u

Explanation:

The average mass of an element is calculated by taking the average of the atomic masses of its stable isotopes.

The enitre atomic mass = 100 % or 1

⇒ this consists of X-85 with 72.17 % abundance  with atomic massof  84.9118 g/mol

72.17 % = 0.7217

⇒ this consists of X-87 with  27.83 % abundance with atomic mass of 86.9092 g/mol

27.83 % = 0.2783

To calculate the mass of this isotope we use the following:

0.7271 * 84.9118 + 0.2783 * 86.9092 =85.468 g/mol

This element is Rubidium(Rb) and has an average atomic mass of 85.468 u

You might be interested in
Anabelle has noticed that her strawberry plants haven't produced any strawberries yet this year.
marusya05 [52]

Answer:0.260

Explanation:

4 0
4 years ago
The cells that allow your bones to move contain bundles of long cylinders. These cells have alternating light and dark bands cal
poizon [28]

Answer:

<h2>Actin and myosin.</h2>

Explanation:

The cells that allow your bones to move, the movement of thick (myosin) and thin (actin) filaments during contraction .

During a contraction thick and thin filaments do not shorten but increase their overlap  of each other.

Thin filaments slide past thick filaments extending more deeply into the A band.

The I bands and H bands decrease in lenght as Z discs are come closer together .

Sarcomere represents area between two Z disc, so the sarcomere gets smaller during a contraction .

8 0
3 years ago
The nuclides I-131 and I-133 are classifieds as
sasho [114]
Isotopes are two atoms with the same number of protons, but a different number of neutrons. Because they have the same number of proton they are atoms of the same element, but with different masses.
so, the answer is c.
i hope this will help you
3 0
4 years ago
Read 2 more answers
If the conjugate base of a molecule has a pkb of 1.4, what would you expect the molecule to be?
maw [93]

If the conjugate base of a molecule has a pKb of 1.4, the molecule should be a Weak Acid.

Notice this question gives us the pKb of the molecule, not the pKa. Because of this, the pH scale basically gets reversed, so lower numbers in pKb correlate with stronger bases, and higher numbers in pKb correlate with stronger acids - the exact opposite of the pH scale.

It's important to make sure you completely understand the terms of conjugate base, conjugate acid, pKb, pKa, and how they all relate. It's easy to mix up the meanings of these definitions.

Here are the two other pieces of information you need to know to correctly answer this question:

  • Strong acids have a weak conjugate base.
  • Strong bases have a weak conjugate acid.

So if the problem says you have a strong conjugate base, then the molecule must be a weak acid. To illustrate this, think of ammonium, NH4+. Ammonium is a weak acid, but the conjugate base of ammonium is ammonia, NH3, which is a reasonably good base.

Learn more about conjugate base here : brainly.com/question/22514615

#SPJ4

3 0
2 years ago
How many moles are there in 3.45 moles of Carbon
VladimirAG [237]

Answer:

It would be 151.832775 because one mole is 44.0095*3.45 i hope this helps!

Explanation:

7 0
3 years ago
Other questions:
  • When a substance melts, is energy being added or removed?
    5·2 answers
  • Lungs function as part of the __________ system and the __________ system.
    12·2 answers
  • Select the correct classification for the reaction.<br> 4NH3(g) + 502(g) – 4NO(g) + 6H20(9)
    12·1 answer
  • The mass of an electron is 9.11× 10–31 kg. What is the uncertainty in the position of an electron moving at 2.00 × 106 m/s with
    15·1 answer
  • Calculate the change in enthalpy (LaTeX: \DeltaΔH) of a reaction with the following information:
    12·1 answer
  • How are scientists able to study the composion of a star that is located out of the solar system
    11·1 answer
  • PLEASE CAN SOMEONE HELP I WILL GIVE BRAINLIEST!!! IF YOU DO ALL 10 QUESTIONS I UPLOAD I WILL GIVE AWAY A LOT OF POINTS!!!
    14·1 answer
  • Ian uses litmus paper to determine whether five unknown solutions are acids or bases. The litmus paper turns red when the pH is
    10·1 answer
  • Which will not appear in the equilibrium constant expression for the reaction below?
    5·1 answer
  • How does it? Please help
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!