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4 years ago

How many moles of carbon are in 7.87*10^7 carbon atoms

Chemistry

2 answers:

iris [78.8K]4 years ago

7 0

Answer:

1.31×10^-16moles

Explanation:

If 1 mole of carbon contains 6.02×10^23 carbon atoms (Avogadro's number)

X moles of carbon contain 7.87×10^7 carbon atoms

X = 7.87×10^7/6.02×10^23

X= 1.31×10^-16moles

Note that 1 moles of any substance contains Avogadro's number of elementary entities (atoms, ions, molecules etc)

bonufazy [111]4 years ago

6 0

There is 7 moles in C

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3 years ago

how do i word a formal letter to a teacher saying i didn't pay attention during the science lessons and i now have no idea what

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Explanation:

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3 years ago

How many moles of Ag+ ions are present in 10 ml of a 0.75 M AgNO3 solution?

lana66690 [7]

Answer:

b. 7.5 x 10^-3

Explanation:

To solve this problem we need to keep in mind the definition of molarity:

Molarity = moles of solute / liters of solution

With the above information in mind it is possible to calculate the moles of solute, given the volume (10 mL) and concentration (0.75 M) of the solution:

First we convert 10 mL to L ⇒ 10 mL / 1000 = 0.01 L

Then we calculate the moles of AgNO₃:

moles of solute = Molarity * Liters of solution

0.01 L * 0.75 M = 7.5x10⁻³ mol AgNO₃

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3 years ago

1. Nuclear decay by alpha particle emission is more common in atoms of elements that:

11111nata11111 [884]

Answer 1) Option a) have an atomic number greater than 83

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$He^{3}_{2} + He^{3}_{2} ----->$ $He^{4}_{2} + 2 P^{1}_{1}$

Two helium isotopes combines to give another helium isotope with emission of a proton (P).

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Answer 4) Option D) All of the above concerns.

Explanation : Nuclear reactions are usually very harmful in nature. It raises many concerns about the waste disposal that is generated from the reaction. It also requires safe operation for the working nuclear plants. It can also be misused for nuclear weapon proliferation. Hence, the answer is all of the above.

Answer 5) False.

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Explanation : In a nuclear reaction, the mass-energy of the reactants is generally less than that of the mass-energy of the products because some energy has to be generated while the reaction is progressing.

Answer 8) Option D) $9.00 X 10^{17} J$