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
Novosadov [1.4K]
3 years ago
11

An element has four naturally occurring isotopes with the masses and natural abundances given in the table below. Find the atomi

c mass of the element (express your answer to four significant figures and include the appropriate units).
Isotope Mass (amu) Abundance (%)
1 203.97304 1.390
2 205.97447 24.11
3 206.97590 22.09
4 207.97665 52.41
Identify the element, by spelling out its full name.
Chemistry
1 answer:
Anestetic [448]3 years ago
6 0

Answer:

Lead (Pb)

Explanation:

To find the atomic mass of the element, we need to take into consideration all the naturally occurring isotopes. We then find the atomic mass by multiplying the natural abundance of the isotopes by their mass for all of the isotopes and summing them together.

1. 1.390/100 * 203.97304 = 2.835225256

2. 24.11/100 * 205.97447 = 49.660444717

3. 22.09/100 * 206.97590 = 45.72097631

4. 52.41/100 * 207.97665 = 109.000562265

We then add all of these masses together:

109.000562265 + 45.72097631+ 49.660444717 + 2.835225256 = 207.217208548

To 4 sf = 207.2 amu

Element is Lead (Pb)

You might be interested in
Help please!!!! I need to know the answer to this problem it would mean a lot if u helped :))
inn [45]
Nobel gas, it is in the last row of the periodic table and therefore is a noble gas
4 0
3 years ago
What pressure is required to compress 196.0 liters of air at 1.83 atmosphere into a cylinder whose volume is 26.0 liters
drek231 [11]

Answer:

P₂ = 13.79 atm

Explanation:

Given data:

Initial volume = 196.0 L

Initial pressure = 1.83 atm

Final volume = 26.0 L

Final pressure = ?

Solution:

The given problem will be solved through the Boyle's law,

"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"

Mathematical expression:

P₁V₁ = P₂V₂

P₁ = Initial pressure

V₁ = initial volume

P₂ = final pressure

V₂ = final volume  

Now we will put the values in formula,

P₁V₁ = P₂V₂

1.83 atm × 196.0 L = P₂× 26.0 L

P₂ = 358.68 atm. L /  26.0 L

P₂ = 13.79 atm  

5 0
3 years ago
My swimming pool is rectangular (16 feet by 34 feet) and has a depth of 6 feet. Lets imagine that my pool water is full to the t
Reil [10]

Answer:

Number of moles of photons required = 5.04 × 10⁴ moles

Explanation:

The energy of a photon can be calculated from Planck's equation E = hc/λ

Where h = 6.63 × 10-³⁴ Js and c, the velocity of light = 3.0 × 10⁸ m/s

Energy of one mole of photons = N₀ × hc/λ

wavelength of photon, λ = 520 nm = 5.20 × 10-⁷ m

Energy of one mole of photons = 6.02 × 10²³ × 6.63 × 10−³⁴ × 3 × 10⁸/5.20 × 10-⁷

Energy of one mole of photons = 2.30 × 10⁵ J/mol

Energy required to raise the temperature of a given mass of a substance, E = mcΔT

Where m is mass of substance,  c is specific heat capacity,  ΔT is temperature difference

Mass ofnwternin the pool = volume × density

Volume of water = Volume of swimming pool

Volume of water = 16 × 34 × 6 ft³ = 3264 ft³

1 ft³ = 28316.8 cm³; 3264 ft³ = 28316.8 × 3264 = 92426035.2 cm³

Density of water = 1 g/cm³

Mass of water = 92426035.2 cm³ × 1 g/cm³ = 92426035.2g

ΔT = 80°C - 50°C = 30°C, c = 4.18 J/g/K

Energy required to raise 92426035.2 g water by 30° C = 92426035.2 × 4.18 × 30

Energy required = 1.16 × 10¹⁰ J

Hence, number of moles of photons required = 1.16 × 10¹⁰ J/2.30 × 10⁵ J/mol

Number of moles of photons required = 5.04 × 10⁴ moles

5 0
3 years ago
the rate of disappearance of Br- at some moment in time was determined to be 3.5 x 10-4 M/s. What is the rate of appearance of B
ddd [48]

Answer:

1.8 × 10⁻⁴ mol M/s

Explanation:

Step 1: Write the balanced reaction

2 Br⁻ ⇒ Br₂

Step 2: Establish the appropriate molar ratio

The molar ratio of Br⁻ to Br₂ is 2:1.

Step 3: Calculate the rate of appearance of Br₂

The rate of disappearance of Br⁻ at some moment in time was determined to be 3.5 × 10⁻⁴ M/s. The rate of appearance of Br₂ is:

3.5 × 10⁻⁴ mol Br⁻/L.s × (1 mol Br₂/2 mol Br⁻) = 1.8 × 10⁻⁴ mol Br₂/L.s

3 0
3 years ago
1.5 moles of Al is how many<br> atoms?
aev [14]

Answer:

<h2>9.03 × 10²³ atoms </h2>

Explanation:

The number of atoms of Al can be found by using the formula

<h3>N = n × L</h3>

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

N = 1.5 × 6.02 × 10²³

We have the final answer as

<h3>9.03 × 10²³ atoms</h3>

Hope this helps you

4 0
2 years ago
Other questions:
  • What is the molar mass of sn(oh)4
    12·1 answer
  • Cortisone consists of molecules, each of which contains 21 atoms of carbon (plus other atoms). the mass percentage of carbon in
    11·1 answer
  • If the density of Mercury is 1.36 × 10 by 4 Kgm - 3 at 0 degrees. Calculate its value at 100 degrees and at 22 degrees. Take cub
    13·1 answer
  • What mineral has 2 sugar-cube sized, irregularly shaped pieces. Brassy-yellow in color with metallic luster. Flat surfaces look
    5·1 answer
  • At a certain temperature, ethane has a vapor pressure of 304 torr and propane has a vapor pressure of 27 torr. What is the mole
    15·1 answer
  • Which is a chemical property of iron?
    11·2 answers
  • What do you know about a substance it you know its temperature? A.How heavy the substance is B.How large or small the particles
    8·2 answers
  • What is the mass of 14.10 moles of Li2O?
    10·1 answer
  • When the temperature of the water was 10°C the waterweed did not produce bubbles.
    6·2 answers
  • Chemistry practice ​
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!