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
Ilia_Sergeevich [38]
3 years ago
6

The mass spectrum of a hypothetical element shows that 78.21% of the atoms have a mass of 27.977 u, 1.346% have a mass of 28.976

u, and the remaining have a mass of 29.974 u. Calculate the average atomic mass of this element (in units of u). (Use 4 Sig. Fig. Don't round until end.)
Chemistry
1 answer:
Crank3 years ago
4 0

Answer: 28.40

Explanation:

For A(27.977 u)

Mass number = 27.977

Abundance = 78.21%

For B (28.976 u)

Mass number = 28.976

Abundance = 1.346%

For C(29.974 u)

Mass number = 29.974

Abundance = 20.444%

Averages atomic mass

= (Mass of A x abundance of A)/100 + (Mass of B x abundance of B)/100 + (Mass of C x abundance of C)/100

= (27.977x78.21)/100 + (28.976x1.346)/100 + (29.974x20.444)/100

= 21.8808117 + 0.39001696 + 6.12788456

= 28.40

You might be interested in
An atom has 16 protons and 18 neutrons. Which symbol represents that atom, including its mass
AlladinOne [14]

Answer:

Sulfur, kill me if I'm wrong

4 0
3 years ago
When a lead acid car battery is recharged by the alternator, it acts essentially as an electrolytic cell in which solid lead(II)
katen-ka-za [31]

Answer:

3.81 g Pb

Explanation:

When a lead acid car battery is recharged, the following half-reactions take place:

Cathode: PbSO₄(s) + H⁺ (aq) + 2e⁻ → Pb(s) + HSO₄⁻(aq)  

Anode: PbSO₄(s) + 2 H₂O(l) → PbO₂(s) + HSO₄⁻(aq) + 3H⁺ (aq) + 2e⁻

We can establish the following relations:

  • 1 A = 1 c/s
  • 1 mole of Pb(s) is deposited when 2 moles of e⁻ circulate.
  • The molar mass of Pb is 207.2 g/mol
  • 1 mol of e⁻ has a charge of 96468 c (Faraday's constant)

Suppose a current of 96.0A is fed into a car battery for 37.0 seconds. The mass of lead deposited is:

37.0s.\frac{96.0c}{s} .\frac{1mole^{-} }{96468c} .\frac{1molPb}{2mole^{-} } .\frac{207.2gPb}{1molPb} =3.81gPb

6 0
3 years ago
Pls someone help ASAP
Alisiya [41]

Answer:

i cant see the picture good

6 0
3 years ago
Help me with this work plz plz
storchak [24]

Answer:

a -4

b - 8

c - 5

d 2

Explanation:

Significant Figures: The number of digits used to express a measured or calculated quantity. By using significant figures, we can show how precise a number is. ... Accuracy: Refers to how closely individual measurements agree with the correct or true value.

7 0
2 years ago
the difference in energy between the n=1 and n=2 energy levels in a hydrogen atom is 1.64x10^-18 J. what happens when an electro
CaHeK987 [17]

Answer:

It emits 1.64 x 10⁻¹⁸J of energy

Explanation:

The n = 1 is a lower quantum level compared to n = 2.

When a hydrogen atom moves from a higher level to a lower one, it simply emits the energy difference between the two levels.

  • If a hydrogen atom moves from a lower energy level to a higher one such as from 1 to 2, they absorb the energy difference to attain the new excited state.
  • So, for an electron in the hydrogen atom to move from a higher energy level to a lower one, it must emit 1.64 x 10⁻¹⁸J of energy.
6 0
3 years ago
Other questions:
  • What happens when light passes from air into water?
    12·1 answer
  • A multivitamin tablet contains 40 milligrams of potassium. how many moles of potassium does each tablet contain?
    5·2 answers
  • How does the equilibrium change to counter the removal of A in this reaction? A + B ⇌ AB The equilibrium . Simultaneously, there
    12·2 answers
  • The _______ are found on the right side of the arrow in a chemical reaction. A. reactants B. products C. subscripts D. coefficie
    7·2 answers
  • Which formula represents a hydrocarbon
    12·2 answers
  • What is the reaction for the formation of FeNCS^2+
    6·1 answer
  • Why doesn’t a broken wineglass spontaneously fix itself, from a thermodynamic point of view?
    9·2 answers
  • In calculating the equilibrium constant for a reaction, the coefficients of the chemical equation are used as exponents for the
    15·1 answer
  • Why won't a fat–soluble vitamin dissolve in water?
    9·1 answer
  • Solids , liquids are the three different states of matter However , they show some similarities of their properties
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!