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
Brrunno [24]
3 years ago
11

A hypothetical element has an atomic weight of 48.68 amu. It consists of three isotopes having masses of 47.00 amu, 48.00 amu, a

nd 49.00 amu. The lightest-weight isotope has a natural abundance of 10.0%. What is the percent abundance of the heaviest isotope?
Chemistry
2 answers:
prohojiy [21]3 years ago
7 0

Answer:

78 %

Explanation:

The atomic mass is the weighted average of the atomic masses of each isotope.

In a weighted average, we multiply each value by a number representing its relative importance.

In this problem, the percent abundance represents the relative importance of each isotope.

Data:

X-47: mass = 47.00 u; abundance = 10.0 % = 0.100  

X-48: mass = 48.00 u  

X-49: mass = 49.00 u

Calculations:

                 Let x = abundance of X-49

Then 0.900 - x = abundance of X-48

\begin{array}{cccc}\\\textbf{Isotope} & \textbf{Mass/u} & \textbf{Abundance} & \textbf{Contribution/u}\\\text{X-47} & 47.00 & 0.100 & 4.700\\\text{X-48} & 48.00 & 0.900 - x & 48.00(0.900 - x)\\\text{X-49} & 49.00 & x & 49.00x\\& \text{TOTAL} & = & \mathbf{48.68}\\\end{array}

\begin{array}{rcr}4.700 + 48.00(0.900 - x) + 49.00x & = & 48.68\\4.700 + 43.20 - 48.00x + 49.00x & = & 48.68\\47.90 +x & = & 48.68\\x & = & \mathbf{0.78}\\\end{array}

The heaviest isotope has an abundance of 78 %.

Morgarella [4.7K]3 years ago
5 0

Answer : The percent abundance of the heaviest isotope is, 78 %

Explanation :

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i

As we are given that,

Average atomic mass = 48.68 amu

Mass of heaviest-weight isotope = 49.00 amu

Let the percentage abundance of heaviest-weight isotope = x %

Fractional abundance of heaviest-weight isotope = \frac{x}{100}

Mass of lightest-weight isotope = 47.00 amu

Percentage abundance of lightest-weight isotope = 10 %

Fractional abundance of lightest-weight isotope = \frac{10}{100}

Mass of middle-weight isotope = 48.00 amu

Percentage abundance of middle-weight isotope = [100 - (x + 10)] %  = (90 - x) %

Fractional abundance of middle-weight isotope = \frac{(90-x)}{100}

Now put all the given values in above formula, we get:

48.68=[(47.0\times \frac{10}{100})+(48.0\times \frac{(90-x)}{100})+(49.0\times \frac{x}{100})]

x=78\%

Therefore, the percent abundance of the heaviest isotope is, 78 %

You might be interested in
A metal entrance door swings freely in the winter, but when
ivann1987 [24]

Answer:

This phenomenon occurs because the door, being metal and leading to changes in temperature, undergoes proportional and morphological changes, metals face expansion and expansion in the presence of heat, called thermal expansion.

On the other hand, against the cold, thermal contraction is suffered, that is why its volume decreases, and it contracts.

Explanation:

The expansion phenomenon of the door is not linear, since it increases its volume in width and height, therefore simultaneously on the entire surface.

When an area or surface expands, it does so by increasing its dimensions in the same proportion. For example, a metal sheet increases its length and width, which means an increase in area. Area dilation differs from linear dilation in that it involves an increase in area.

The area expansion coefficient is the increase in area that a body of a certain substance experiences, with an area equal to unity, as its temperature rises one degree centigrade. This coefficient is represented by the Greek letter gamma.

Regarding shrinkage, a clear example of this is when a metal foundry or a weld shrinks, sometimes it is difficult to understand with examples like these (doors) because it is little noticeable by our eyes and the dimensional changes for our perspective. it is infima.

3 0
3 years ago
Which of the following causes high and low tides on Earth? A. The moon's gravitational pull on Earth causes water to bulge on tw
Finger [1]
A. the moon's gravitational pull on earth causes water to bulge on two sides of the earth
5 0
3 years ago
Read 2 more answers
How many atoms are in ErAg
Semmy [17]
6.022 * 10^23 atoms
3 0
3 years ago
Zinc oxide adopts a face-centered cubic arrangement. Both Zinc ions and oxide ions adopt the face-centered cubic arrangement; wi
vichka [17]

Answer:

5.41 ×10⁻²²

Explanation:

We were told right from the question that both the Zinc ions and the Zinc oxide adopts a face-centered cubic arrangement.

Then, the number of ZnO molecule in one unit cell = 4

The standard molar mass of ZnO = 81.38g

Avogadro's constant = 6.023 × 10²³ mole

∴

The mass of one unit cell of zinc oxide can be calculated as:

= \frac{4*81.38}{6.023*10^{23}}

= 5.40461564×10⁻²²

≅ 5.41 ×10⁻²²

∴ The mass of one unit cell of zinc oxide = 5.41 ×10⁻²²

3 0
2 years ago
If the temperature of a liquid-vapor system at equilibrium increases, the new equilibrium condition will
nikdorinn [45]
If the temperature of a liquid-vapor system at equilibrium increases, it will shift towards the vapor phase, assuming that the pressure remains equal. The concentration of vapor will also increase relative to the concentration of liquid in the system. Thus, the new equilibrium condition will have more vapor than liquid. 
6 0
2 years ago
Other questions:
  • Explain how mixture melting points can be used to distinguish between two compounds
    8·1 answer
  • Which statement is true of unstable isotopes?
    9·1 answer
  • Draw all constitutional isomers with molecular formula c3h8o, and rank them in terms of increasing acidity:
    7·1 answer
  • Two atoms With diferent mass number but the same atomic number are called​
    15·1 answer
  • describe how astronomers are able to use the light from a distant star to determine what elements make up the stars.
    8·1 answer
  • Someone pleaseeeeee helppp
    14·1 answer
  • Pls help !! it’s a timed quiz answer
    15·1 answer
  • If 42.389 g of Fe3Br2 is dissolved in enough water to give a total volume of 750 mL, what is the molarity of the solution
    9·1 answer
  • Predict the products for the reaction shown in the picture. <br> Fe(s) + CuCrO4(aq) —&gt;
    8·1 answer
  • Two seventh grade students are studying how sound waves are transferring energy.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!