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Fittoniya [83]
3 years ago
5

Someone help please.

Chemistry
1 answer:
mojhsa [17]3 years ago
6 0

After 3 half life periods you would have 5 grams of krypton left because half of 40 is 20 half of 20 is 10 and half of 10 is 5

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In determining nuclear binding energy, what is Einstein's equation used to do?
natita [175]
Basically this is used in calculating the nuclear binding energy by converting the mass defect (calculated first) to energy and if we recall, Einstein's equation E=mc2 is the perfection equation to use because E=mc2 in which E represents units of energy, m represents units of mass, and c 2 is the speed of light squared. 
3 0
3 years ago
What is the empirical formula of a compound containing 12 g of carbon, 2 g of hydrogen, and 16 g of oxygen only
Hoochie [10]

Answer:

The empirical formula=CHO. To explain it is C1H1O1 but we don't put the one that's why it is CHO

Explanation:

7 0
3 years ago
Use the rules (in order) to assign oxidation numbers to each of the elements in the compounds below.
xz_007 [3.2K]

Answer:

Explanation:

The oxidation number is an integer that represents the number of electrons that an atom receives or makes available to others when it forms a given compound.

The oxidation number is positive if the atom loses electrons, or shares them with an atom that has a tendency to accept them. And it will be negative when the atom gains electrons, or shares them with an atom that has a tendency to give them up.

Chemical compounds are electrically neutral. That is, the charge that all the atoms of a compound contribute must be globally null. That is, when having positive or negative charges in a compound, their sum must be zero.

There are some rules for determining oxidation numbers in compounds. Among them it is possible to mention:

  • Hydrogen (H) has an oxidation number +1 with nonmetals and - 1 with metals.
  • Oxygen (O) presents the oxidation number -2
  • Fluorine F has a unique oxidation state -1

Then:

  • NOF: N+(-2)+(-1)=0 → N=3 → oxidation number of  nitrogen (N) is +3, oxidation number of oxygen (O) is -2 and oxidation number of  fluorine (F) is -1.
  • ClF₅: Cl + 5*(-1)=0 → Cl= 5 → oxidation number of  chlorine (Cl) is +5 and oxidation number of  fluorine (F) is -1.
  • H₂SO₃: 2*(+1)+S+3*(-2)=0 → S=4 → oxidation number of hydrogen (H) is +1, oxidation number of oxygen (O) is -2 and oxidation number of sulfur (S) is +4.
8 0
3 years ago
63Ni decays by a first-order process via the emission of a beta particle. The 63Ni isotope has a half-life of 100. years. How lo
rewona [7]

Answer:

151.4863 years

Explanation:

Half life, t1/2 = 100 years

Initial concentration,[A]o = 100%

Final concentration, [A] = 35% (after 65% have been decayed)

Time = ?

Half life for a first Order reaction is given as;

t1/2 = ln (2) / k

k = ln(2) / 100

k = 0.00693y-1

The integral rate law for first order reactions is given as;

ln[A] = ln[A]o − kt

kt = ln[A]o - ln[A]

t = ( ln[A]o - ln[A]) / k

t = [ln(100) - ln(35)] /0.00693

t = 1.0498 / 0.00693

t = 151.4863 years

8 0
3 years ago
-QUESTION 5-
vodomira [7]
The tall trees much of the sun
have you ever been in a forest? if you have, you’ve probably noticed that it’s usually very shady, and not a lot of sunlight hits the ground. That’s cause the tall trees are so dense, the sunlight doesn’t reach the ground
5 0
3 years ago
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