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lutik1710 [3]
3 years ago
12

After two half-lives, the amount of radioactive substance remaining will be

Chemistry
1 answer:
Elan Coil [88]3 years ago
4 0

Answer:

A 25% of the initial parent nuclei.

Explanation:

One half life, you get 50%, two half lives you get 25% and you just keep dividing by 2 from there. :) Good luck my friend!

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Be sure to answer all parts. the equilibrium constant (kp) for the reaction below is 4.40 at 2000. k. h2(g) + co2(g) ⇌ h2o(g) +
svetoff [14.1K]
When we have the balanced reaction equation is:

H2(g)  + CO2(g) ↔ H2O(g)  + CO (g)

a) first, to calculate ΔG° for the reaction: 

we will use this formula:

ΔG° = -RT㏑Kp

when R is R- rydberg constant = 8.314J/mol.K

and T is the temperature in Kelvin = 2000 K

and Kp = 4.4 

so, by substitution:

ΔG° = - 8.314 *2000 *㏑4.4

        = - 24624 J/mol = - 24.6 KJ/mol

b) to calculate ΔG so, we will use this formula:

ΔG = ΔG° + RT㏑Qp

So we need first, to get Qp from the reaction equation:

when Qp = P products / P reactants

                 =  PH2O*PCO / PH2 * PCO2

                 = (0.66 atm * 1.2 atm) / (0.25 * 0.78)

                 = 4.1 

so by substitution:

ΔG = -24624 + 8.314*2000*㏑4.1

      = -1162 J/mol = - 1.16 KJ/mol
7 0
4 years ago
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a. Compare the motion of the particles as a solid, liquid, and gas. b. What happens to the intermolecular bonds during phase cha
natta225 [31]
The answer A I’m positively absolutely
3 0
3 years ago
An ionic bond occurs between what particles?
LenKa [72]
because a postive and negative can be used in. ion

5 0
3 years ago
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An element's most stable ion forms an ionic compound with bromine, having the formula XBr. If the ion of element X has a mass nu
earnstyle [38]

Answer:

The element is Rubidium . The ion only loss one electron to make the electron 36 . But the proton number(atomic number) is 37. The chemical compound should RbBr

X = Rubidium(Rb)

Explanation:

The ion of element X has a mass number of 85 and electron of 36. An elements is charge if it either loss or receive electron. Base on the charge the ion  has loss electron. Bromine usually possess a negatively charge ion. That makes the X electron a positively charge ion.

proton number = Atomic number

Proton number = electron number when not charged

Mass number = proton number + neutron number

Proton is usually same number with the electron to make the element neutral. But when the atom is charge the atom usually loss or gain electron.

In this case, the atom X loss one electron thereby reducing the electron number to 36 . Recall, the electron is equal to proton only if the atom is uncharged.  This means the proton number should be 37 as one electron was loss.

Element with proton number(atomic number) of 37 is rubidium. It is an alkali metal that is very reactive.

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4 years ago
Help me with my work please thanks?!
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Answer:

lighting a match or water and salt

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