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Eddi Din [679]
2 years ago
9

A radioactive substance of mass 768g has a half life of 3 years. After how many years does it leave only 6g undecayed?​

Chemistry
2 answers:
vagabundo [1.1K]2 years ago
8 0

Answer:

The answer is 21 years.

Explanation:

7×3

sammy [17]2 years ago
5 0

Answer:

hi

good morning

myself veeresh

and you

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How many grams of water can be formed from the reaction of 8.76 grams of H2 with 10.5 liters of O2 (at STP) according to the bal
Kisachek [45]

Answer:

16.9g of H₂O can be formed

Explanation:

Based on the chemical reaction, 2 moles of H₂ react per mole of O₂. To anser this question we must find limiting reactant converting the mass and volume of each reactant to moles:

<em>Moles H₂ -Molar mass: 2.016g/mol-:</em>

8.76g * (1mol / 2.016g) = 4.345 moles

<em>Moles O₂:</em>

PV = nRT

PV/RT = n

P = 1atm at STP

V = 10.5L

R = 0.082atmL/molK

T = 273.15K at STP

n = 1atm*10.5L / 0.082atmL/molK*273.15K

n = 0.469 moles of oxygen

For a complete reaction of 4.345 moles moles of hydrogen are required:

4.345 moles H2 * (1mol O2 / 2mol H2) = 2.173 moles of O2 are required. As there are just 0.469 moles, Oxygen is limiting reactant

Now, 1 mole of O2 produce 2 moles of H2O. 0.469 moles will produce:

0.469 moles O₂ * (2 moles H₂O / 1mol O₂) = 0.938 moles H₂O.

The mass is -Molar mas H₂O = 18.01g/mol-:

0.938 moles * (18.01g/mol) =

<h3>16.9g of H₂O can be formed</h3>
8 0
3 years ago
The President's Challenge Program is a fitness evaluation designed for __________.
lara [203]
Hi there!

I believe the answer to this is B. Elementary and High school students.

Hope this helps! ☺♥
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3 years ago
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At STP, fluorine is a gas and iodine is a solid. This observation can be explained by the fact that fluorine has
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<span>The answer is 4. The molecules of each material entice each other over dispersion (London) intermolecular forces. Whether a substance is a solid, liquid, or gas hinge on the stability between the kinetic energies of the molecules and their intermolecular magnetisms. In fluorine, the electrons are firmly apprehended to the nuclei. The electrons have slight accidental to stroll to one side of the molecule, so the London dispersion powers are comparatively weak. As we go from fluorine to iodine, the electrons are far from the nuclei so the electron exhausts can more effortlessly misrepresent. The London dispersion forces developed to be increasingly stronger.</span>
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3 years ago
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Write empirical formula
andrew11 [14]

Answer:

Pb(ClO_{3})_{4}\\Pb(MnO_{4})_{4}\\Fe(ClO_{3})_{3}\\\Fe(MnO_{4})_{3}\\

Explanation:

Pb^{4+}(ClO_{3}^{-})_{4}--->Pb(ClO_{3})_{4}\\Pb^{4+}(MnO_{4}^{-})_{4}--->Pb(MnO_{4})_{4}\\Fe^{3+}(ClO_{3}^{-})_{3}--->Fe(ClO_{3})_{3}\\\Fe^{3+}(MnO_{4}^{-})_{3}--->Fe(MnO_{4})_{3}\\

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29.3g CO2 and 20.8g H2O
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the most best answer is 50.1 you never find such type of answer

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