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
Darya [45]
3 years ago
14

The average atomic mass of Eu is 151.96 amu. There are only two naturally occurring isotopes of europium, Eu with a mass of 151.

0 amu and Eu with a mass of 153.0 amu. The natural abundance of the Eu isotope must be approximately
Chemistry
1 answer:
earnstyle [38]3 years ago
7 0

Answer:

The percentage abundance of Eu isotopes are 52 %  and 48 % .

Explanation:

The formula for the calculation of the average atomic mass is:

Average\ atomic\ mass=(\frac {\%\ of\ the\ first\ isotope}{100}\times {Mass\ of\ the\ first\ isotope})+(\frac {\%\ of\ the\ second\ isotope}{100}\times {Mass\ of\ the\ second\ isotope})

Given that:

Since the element has only 2 isotopes, so the let the percentage of first be x and the second is 100 -x.

For first isotope,:

% = x %

Mass = 151.0 amu

For second isotope :

% = 100  - x  

Mass = 153.0 amu

Given, Average Mass = 151.96 amu

Thus,

151.96=\frac{x}{100}\times {151.0}+\frac{100-x}{100}\times {153.0}

Solving for x, we get that:

x = 52 %

<u>Thus percentage abundance of Eu isotopes are 52 %  and 48 % .</u>

You might be interested in
What is the cell potential of an electrochemical cell that has the half -reactions shown below? Ni^ 2+ +2e Ni A| A|^ 3+ +3e^ -
Nadya [2.5K]
<h3>Answer:</h3>

A. 1.4 V

<h3>Explanation:</h3>

We are given the half reactions;

Ni²⁺(aq) + 2e → Ni(s)

Al(s) → Al³⁺(aq) + 3e

We are required to determine the cell potential of an electrochemical cell with the above half-reactions.

E°cell = E(red) - E(ox)

From the above reaction;

Ni²⁺ underwent reduction(gain of electrons) to form Ni

Al on the other hand underwent oxidation (loss of electrons) to form Al³⁺

The E.m.f of Ni/Ni²⁺ is -0.25 V and that of Al/Al³⁺ is -1.66 V

Therefore;

E°cell = -0.25 V - (-1.66 V)

         = -0.250V + 1.66 V

         = + 1.41 V

         = + 1.4 V

Therefore, the cell potential will be +1.4 V

3 0
3 years ago
What is the formula for calcium carbonate?
mote1985 [20]
The formula is CaCO3
6 0
3 years ago
A 13.5g sample of gold is heated, then placed in a calorimeter containing 60g of water. The temperature of water increases from
sweet-ann [11.9K]

Answer:

T_i~=163.1 ºC

Explanation:

We have to start with the variables of the problem:

Mass of water = 60 g

Mass of gold = 13.5 g

Initial temperature of water= 19 ºC

Final temperature of water= 20 ºC

<u>Initial temperature of gold= Unknow</u>

Final temperature of gold= 20 ºC

Specific heat of gold = 0.13J/gºC

Specific heat of water = 4.186 J/g°C

Now if we remember the <u>heat equation</u>:

Q_H_2_O=m_H_2_O*Cp_H_2_O*deltaT

Q_A_u=m_A_u*Cp_A_u*deltaT

We can relate these equations if we take into account that <u>all heat of gold is transfer to the water</u>, so:

m_H_2_O*Cp_H_2_O*deltaT=~-~m_A_u*Cp_A_u*deltaT

Now we can <u>put the values into the equation</u>:

60~g*4.186~J/g{\circ}C*(20-19)~{\circ}C=-(13.5~g*0.13~J/g{\circ}C*(20-T_i)~{\circ}C)

Now we can <u>solve for the initial temperature of gold</u>, so:

T_i~=(\frac{60~g*4.186~J/g{\circ}C*(20-19)~{\circ}C}{13.5~g*0.13~J/g{\circ}C})+20

T_i~=163.1 ºC

I hope it helps!

5 0
2 years ago
Which of the following correctly describes one way that photosynthetic plants are involved in the carbon cycle? Choose 1 answer:
brilliants [131]

Answer:

The correct answer is - (Choice A) A Photosynthetic plants can move carbon from the atmosphere into an ecosystem’s food web.

Explanation:

Photosynthesis is the process performed by photosynthetic or green plants in presence of light atmospheric carbon dioxide and water converted into glucose (6 carbon compound) and oxygen.

This glucose or sugar is utilized by the plants that are producers in the ecosystem food web. These producers are fed by consumers and carbon molecules transfer from all the trophic levels in the food chain or food web in the process.

7 0
3 years ago
Which equation is balanced?
vichka [17]

Answer:

2Na+F2 yields 2NaF is balanced.

Explanation:

There are 2 sodium and 2 fluorine in both reactants and product: In 2NaF the 2 is distributed because it is in the beginning of the compound.

7 0
3 years ago
Read 2 more answers
Other questions:
  • HELP ASAP WILL GIVE BRAINLIESET How long is it between low tides for most places on Earth? A. about 12 hours B. about 24 hours C
    13·2 answers
  • Why don't we estimate an additional number on an electrical balance?​
    12·1 answer
  • the student measured the volume of water as 80.0 mL. she discovered that the actual volume was 80.1 mL. is her results ac urate
    11·2 answers
  • How many grams of iron metal do you expect to be produced when 325 grams of an 87.5 percent by mass iron (II) nitrate solution r
    10·1 answer
  • Manganese(II) oxide, lead(IV) oxide, and nitric acid react to produce permanganic acid, lead(II) nitrate, and water according to
    12·1 answer
  • Which chemical symbols will complete the equation for this single displacement reaction?
    12·2 answers
  • Helpppppppppppppppppppppppppppppppppppppppp
    12·2 answers
  • D) Evaluate your answer and explain why your answer makes sense​
    14·1 answer
  • A
    6·1 answer
  • 25 Points! A flashlight uses the chemical energy stored in a battery. This chemical energy is eventually converted into which tw
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!