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
lesya [120]
3 years ago
10

The half life of radium-226 is 1600 years. How many grams of a 0.25g sample will remain

Chemistry
1 answer:
myrzilka [38]3 years ago
4 0

Answer:

Explanation:

half life = 1600 years .

m = M  x ( \frac{1}{2} )^n

m is mass of the radioactive object after n half lives , M is original mass.

n = 4800 / 1600

= 4

Putting the valus of n and M we have

m = .25 x ( \frac{1}{2} )^3

= .03125 g .

You might be interested in
Select the correct answer.
Serjik [45]

Ionic bond is a chemical bond formed by the complete transfer of electrons between two atoms. The atom that loses electrons gains a positive charge (cation) and that which accepts electrons gains a negative charge (anion). Now, electronegativity is a parameter that measures the tendency of an atom to accept electrons. In the context of ionic bonding, two elements which show a significant difference in their electronegativity values form ionic bonds.

In the given examples, the difference in electronegativity is greatest between K  and Br i.e. 0.8 and 2.8 respectively with a difference of 2.0. This also makes sense since K and Br are on the extreme ends of the periodic table. Hence, potassium with a valence electron configuration of 4s1 will lose its s electron to Br (4s24p6) and form an ionic molecule K⁺Br⁻

Ans E) potassium and bromine

8 0
3 years ago
Read 2 more answers
The second-order diffraction for a gold crystal is at an angle of 22.20o for X-rays of 154 pm. What is the spacing between the c
Alenkinab [10]

<u>Answer:</u> The spacing between the crystal planes is 4.07\times 10^{-10}m

<u>Explanation:</u>

To calculate the spacing between the crystal planes, we use the equation given by Bragg, which is:

n\lambda =2d\sin \theta

where,

n = order of diffraction = 2

\lambda = wavelength of the light = 154pm=1.54\times 10^{-10}m     (Conversion factor:  1m=10^{12}pm )

d = spacing between the crystal planes = ?

\theta = angle of diffraction = 22.20°

Putting values in above equation, we get:

2\times 1.54\times 10^{-10}=2d\sin (22.20)\\\\d=\frac{2\times 1.54\times 10^{-10}}{2\times \sin (22.20)}\\\\d=4.07\times 10^{-10}m

Hence, the spacing between the crystal planes is 4.07\times 10^{-10}m

4 0
3 years ago
How is ozone produced?
zubka84 [21]
The answer is A. the solar ultraviolet ray breaks the molecule apart
3 0
3 years ago
Read 2 more answers
Who is Alfred Wegener? What did he discover?
Aliun [14]

Answer:

Alfred Wegener proposed the theory of continental drift – the idea that Earth's continents move. Despite publishing a large body of compelling fossil and rock evidence for his theory between 1912 and 1929, it was rejected by most other scientists.

Hope this helps!

3 0
3 years ago
CS2 (s) + 3 O2 (g) → CO2 (g) + 2 SO2 (g)
Natasha_Volkova [10]

Answer:

2.067 L ≅ 2.07 L.

Explanation:

  • The balanced equation for the mentioned reaction is:

<em>CS₂(g) + 3O₂(g) → CO₂(g) + 2SO₂(g),</em>

It is clear that 1.0 mole of CS₂ react with 3.0 mole of O₂ to produce 1.0 mole of CO₂ and 2.0 moles of SO₂.

  • At STP, 3.6 L of H₂ reacts with (?? L) of oxygen gas:

It is known that at STP: every 1.0 mol of any gas occupies 22.4 L.

<u><em>using cross multiplication:</em></u>

1.0 mol of O₂ represents → 22.4 L.

??? mol of O₂ represents → 3.1 L.

∴ 3.1 L of O₂ represents = (1.0 mol)(3.1 L)/(22.4 L) = 0.1384 mol.

  • To find the no. of moles of SO₂ produced from 3.1 liters (0.1384 mol) of hydrogen:

<u><em>Using cross multiplication:</em></u>

3.0 mol of O₂ produce → 2.0 mol of SO₂, from stichiometry.

0.1384 mol of O₂ produce → ??? mol of SO₂.

∴ The no. of moles of SO₂ = (2.0 mol)(0.1384 mol)/(3.0 mol) = 0.09227 mol.

  • Again, using cross multiplication:

1.0 mol of SO₂ represents → 22.4 L, at STP.

0.09227 mol of SO₂ represents → ??? L.

∴ The no. of liters of SO₂ will be produced = (0.09227 mol)(22.4 L)/(1.0 mol) = 2.067 L ≅ 2.07 L.

8 0
3 years ago
Other questions:
  • What is cassini considered?
    5·1 answer
  • How does climate determine the organisms that live in a biome
    14·1 answer
  • Once the reaction has occurred as completely as possible, what mass (in g) of the excess reactant is left
    14·1 answer
  • CH2OHCH2OH is a general example of: an ethyl alcohol a methyl alcohol a polyhydroxyl alcohol an organic acid
    12·2 answers
  • An element is a mixture of two isotopes.one isotope has an atomic mass of 34.969 amu and an abundance of 64.88
    10·1 answer
  • Which of the following statements best describes the number of neutrons in an atom?
    12·1 answer
  • How does the immune system uses feedback mechanisms?
    15·1 answer
  • What was the hiker's average velocity during part C of the hike?
    6·2 answers
  • A soccer player kicks a soccer ball. The ball travels 20 meters before landing on the ground. The ball stayed in the air for 5 s
    15·1 answer
  • Describe how you could show by adding aqueous sodium hydroxide and aqueous ammonia that a solution contained zinc ions.
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!