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
mixas84 [53]
4 years ago
13

An unkown element has been found to occur in two different stable isotopes. One isotope has an abundance of 57.21 percent and ha

s a mass of 120.9 amu. The other isotope has an abundance of 42.79 percent and has a mass of 122.9 amu. What is the average atomic mass of the unknown element?
Chemistry
1 answer:
NeX [460]4 years ago
6 0

Answer: 121.7558 amu

Explanation:

Average atomic mass of the unknown element =

(Mass of isotope 1 x Relative Abundance of Isotope 1) + ( Mass of Isotope 2 x Relative Abundance of Isotope 2)

(120.9 x 0.5721) + (122.9 x 0.4279) = 69.16689 + 52.58891

Average mass of the unknown element = 121.7558 amu

You might be interested in
A neutral atom has 1 valence electron and its atomic mass is 39. How many
uranmaximum [27]

Answer: I think probaly wrong so probaly dont

listen to me

Explanation:

5 0
3 years ago
To determine the concentration of SO4 2– ion in a sample of groundwater, 100.0 mL of the sample is titrated with 0.0250 M Ba(NO3
Brrunno [24]

Answer:

1.87x10⁻³ M SO₄²⁻

Explanation:

The reaction of SO₄²⁻ with Ba²⁺ (From Ba(NO₃)₂) is:

SO₄²⁻(aq) + Ba²⁺(aq) → BaSO₄(s)

<em>Where 1 mole of  SO₄²⁻ reacts per mole of Ba²⁺</em>

<em />

To reach the end point in this titration, we need to add the same moles of Ba²⁺ that the moles that are of SO₄²⁻.

Thus, to find molarity of SO₄²⁻ we need to find first the moles of Ba²⁺ added (That will be the same of SO₄²⁻). And as the volume of the initial sample was 100mL we can find molarity (As ratio of moles of SO₄²⁻ per liter of solution).

<em>Moles Ba²⁺:</em>

7.48mL = 7.48x10⁻³L ₓ (0.0250moles / L) = 1.87x10⁻⁴ moles of Ba²⁺ = Moles of SO₄²⁻

<em>Molarity SO₄²⁻:</em>

As there are 1.87x10⁻⁴ moles of SO₄²⁻ in 100mL = 0.1L, molarity is:

1.87x10⁻⁴ moles of SO₄²⁻ / 0.1L =

<h3> 1.87x10⁻³ M SO₄²⁻</h3>
8 0
3 years ago
4. Rock is broken down as a result of chemical reactions;
tekilochka [14]

Answer:

A

Explanation:

CHEMICALS WEATHER IN CHEMICAL WEATHERING

7 0
3 years ago
Read 2 more answers
In the "Design a Thermos" lab, the temperature of the thermos was compared with a container that was not insulated.
Hitman42 [59]

Answer:

B

Explanation:

so you can see the difference

8 0
3 years ago
Read 2 more answers
All of the following are true except foreshocks can happen before an earthquake aftershocks can happen after an earthquake fores
Snowcat [4.5K]
Foreshocks and aftershocks can happen at the same time is not true. 
4 0
3 years ago
Other questions:
  • When calculating global population growth, the death rate is _____.
    14·2 answers
  • Sodium-24 has a half life how much sodium-24 will remain in an 18 g sample after 75 hours
    15·1 answer
  • 20 POINTS PLZ ANSWER FAST !!!!!!!!!!!!!!!!!!
    7·1 answer
  • Can someone double check my work? (Ideal Gas Law Equation)
    7·1 answer
  • Please hurry Which of the following statements is true?
    14·1 answer
  • 1. How many atoms of chlorine are present in 1.70x1023 molecules Cl2?​
    11·1 answer
  • What type of bond (Ionic, Covalent or Metallic) would be created when carbon bonds with bromine?
    11·1 answer
  • How many atoms of each element are in one molecule of the product?
    10·2 answers
  • Four students presented different analogies to describe the formation of an ionic bond.
    12·2 answers
  • Which isoelectronic series is correctly arranged in order of increasing radius?.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!