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4 years ago

18. The mass of a quantity of NiCl2 is 24.6 g. How many formula units are in the sample?

Chemistry

2 answers:

MrRissso [65]4 years ago

8 0

its not A for sure becz i took the test i but b 1.9 3 1027 NiCl2 formula units

it was wrong answer

Charra [1.4K]4 years ago

4 0

Answer is: A. 1.1 3 1023 NiCl2 formula units.

m(NiCl₂) = 24.6 g; mass of nickel(II) chloride.

M(NiCl₂) = 129.6 g/mol; molar mass of nickel(II) chloride.

n(NiCl₂) = m(NiCl₂) ÷ M(NiCl₂).

n(NiCl₂) = 24.6 g ÷ 129.6 g/mol.

n(NiCl₂) = 0.19 mol; amount of nickel(II) chloride.

Na = 6.022·10²³ 1/mol; Avogadro constant.

N(NiCl₂) = n(NiCl₂) · Na.

N(NiCl₂) = 0.19 mol · 6.022·10²³ 1/mol.

N(NiCl₂) = 1.13·10²³; number of formula units.

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iragen [17]

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4 years ago

How many moles of H2 are produced from 5.8 moles of NH3

vodomira [7]

Answer:

1. 8.7moles of H2

2. 2.25moles of O2

Explanation:

1. 2NH3 —> N2 + 3H2

From the equation,

2moles of NH3 produce 3 moles of H2.

Therefore, 5.8moles of NH3 will produce Xmol of H2 i.e

Xmol of H2 = (5.8x3)/2 = 8.7moles

2. C3H8 + 5O2 —> 3CO2 + 4H2O

From the equation,

5moles of O2 produced 4moles of H2O.

Therefore, Xmol of O2 will produce 1.8mol of H2O i.e

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4 years ago

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Kamila [148]

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3 years ago

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3 years ago

During a chemical reacion, an iron atom beacme the ion Fe+2. what happened to the iron atom?

galben [10]

Answer:

That iron atom is oxidized. It loses two electrons.

Explanation:

Compare the formula of an iron atom and an iron(II) ion:

Iron atom: $\mathrm{Fe}$ ;
Iron(II) ion: $\mathrm{Fe^{2+}}$ .

The superscript $+2$ in the iron(II) ion is the only difference between the two formulas. This superscript indicates a charge of $+2$ on each ion. Atoms and ions contain protons. In many cases, they also contain electrons. Each proton carries a positive charge of $+1$ and each electron carries a charge of $-1$ . Atoms are neutral for they contain an equal number of protons and electrons.

Protons are located at the center of atoms inside the nuclei. They cannot be gained or lost in chemical reactions. However, electrons are outside the nuclei and can be gained or lost. When an atom loses one or more electrons, it will carry more positive charge than negative charge. It will becomes a positive ion. Conversely, when an atom gains one or more electrons, it becomes a negative ion.

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This definition can be written as the acronym OILRIG. (Khan Academy.)

In this case, each iron atom loses two electrons. Therefore the iron atoms here are oxidized.

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3 years ago