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1 year ago

How many moles are in 91.5 grams of Helium?

1 answer:

4 0

In order to find the number of moles with a given mass of Helium, we need to use its molar mass, which is 4.0026g/mol, therefore we will have:

4.0026g = 1 mol of Helium

91.5g = x moles of Helium

x = 22.86 moles of Helium in 91.5 grams

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alekssr [168]

Answer:

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the numbers 12, 13, and 14 refer to the ATOMIC MASS

how many protons and neutrons are in the first isotope?

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2 years ago

The student plans to conduct a spectrophotometric analysis to determine the concentration of Cu2+(aq) in a solution. The solutio

mestny [16]

Answer:

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Explanation:

Attached below you can find the diagram I found for this question elsewhere.

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At 400 nm Co⁺²(aq) shows no absorbance, however neither does Cu⁺²(aq). While at 700 nm Co⁺²(aq) shows no absorbance and Cu⁺²(aq) does.

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2 years ago

If an atom or ion has an atomic number of 3, 2 electrons, and the electronic configuration is 2, what is the mass number?

rjkz [21]

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3 years ago

Uranium is a metallic element that is used in nuclear reactors and nuclear weapons. the vast majority of uranium found on earth

katrin [286]

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3 years ago

Use the equation n2 + 3h2=2nh3 if 8.0g N2 react, how many grams of NH3 will be produced

Eduardwww [97]

the balanced equation for the formation of ammonia is

N₂ + 3H₂ ---> 2NH₃

molar ratio of N₂ to NH₃ is 1:2

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therefore number of N₂ moles reacted is - 8.0 g / 28 g/mol = 0.286 mol

according to the molar ratio,

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therefore 0.286 mol of N₂ should give - 2 x 0.286 mol = 0.572 mol of NH₃

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a mass of 9.72 mol of NH₃ is formed

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3 years ago