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jeka94
3 years ago
14

An element has three naturally occurring isotopes. The relative abundances of the isotopes are 0.27%, 9.25%, and 90.48%. The mos

t abundant isotope has an atomic mass of 19.99 amu. The least abundant isotope has an atomic mass of 20.99 amu, and the remaining isotope has an atomic mass of 21.99 amu.
Based on these data, what is the average atomic mass of this element? (Round your answer to the nearest hundredth and do not enter units in your answer.)
Chemistry
1 answer:
Nat2105 [25]3 years ago
8 0

Answer

20.18

Explanation:

The atomic mass of X is the <em>weighted average</em> of the atomic masses of its isotopes.

We multiply the atomic mass of each isotope by a number representing its <em>relative importance</em> (i.e., its percent of the total).

Set up a table for easy calculation

0.9048 ×  19.99 u = 18.087   u

0.0027 × 20.99 u =  0.0567 u

0.0925 × 21.99  u =  <u>2.0341  u </u>

                TOTAL = 20.18      u

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Is Oxygen - O2 a pure substance or a mixture?
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Need help I don’t understand this at all need to show my work and strategy it’s stoichiometry gram to gram please help
laila [671]

Answer:

781×10¯² g of MgCl₂.

Explanation:

The balanced equation for the reaction is given below:

Mg + 2HCl —> MgCl₂ + H₂

Next, we shall determine the mass of HCl that reacted and the mass of MgCl₂ produced from the balanced equation. This is illustrated below:

Molar mass of HCl = 1 + 35.5

= 36.5 g/mol

Mass of HCl from the balanced equation = 2 × 36.5 = 73 g

Molar mass of MgCl₂ = 24 + (35.5×2)

= 24 + 71

= 95 g/mol

Mass of MgCl₂ from the balanced equation = 1 × 95 = 95 g

SUMMARY:

From the balanced equation above,

73 g of HCl reacted to produce 95 g of MgCl₂.

Finally, we shall determine the mass of MgCl₂ produced by the reaction of 6 g of HCl. This can be obtained as follow:

From the balanced equation above,

73 g of HCl reacted to produce 95 g of MgCl₂.

Therefore, 6 g of HCl will react to produce = (6 × 95)/73 = 781×10¯² g of MgCl₂.

Thus, 781×10¯² g of MgCl₂ were obtained from the reaction.

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a_sh-v [17]

Answer:

the top one is 100.000 and bottom one is 100.000

Explanation:

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Read 2 more answers
What is the speed of a horse in meters per second that runs a distance of 1.2 miles in 2.4 minutes? (Hint: 1 mile = 1609 m)
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Time t=2.4 minutes=2.4×60=144 seconds
distance s=1.2 miles=1.2×1609=1930.8 meters
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4 years ago
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