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3 years ago

How many moles are in 25.0 grams of KMnO4?

Chemistry

1 answer:

Lilit [14]3 years ago

3 0

Answer:- 0.158 moles

Solution:- Moles are calculated on dividing the grams by the molar mass.

25.0 grams of $KMnO_4$ are given and we are asked to calculate the moles.

For this we need the molar mass so let's calculate it first.

Molar mass is the sum of atomic masses of all the atoms present in the molecule.

Molar mass = $39.098+54.938+4(16)$

= 158.036 gram per mol

Now, we will divide the given grams by molar mass to get the moles and the set is shown as:

$25.0gKMnO_4(\frac{1mol}{158.036g})$

= $0.158molKMnO_4$

So, there are 0.158 moles of $KMnO_4$ .

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<h3>Further explanation</h3>

Given

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For first-order reaction :

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Input the value :

ln(0.040)=-(0.029)t+ln(0.050)

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3 years ago

The rate of a certain reaction is given by the following rate law: rate Use this information to answer the question below. At a

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Answer:

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Explanation:

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Initial rate of the reaction = R = $4.0\times 10^5 M/s$

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The initial rate of the reaction when concentration of hydrogen gas is doubled : R'

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3 years ago

What is the weight in grams of 3.36 × 10Æ³ molecules of copper sulfate (CuSOÁ)?

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3 years ago

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Mass of any substance can be calculated by using moles as:

n = W/M, where

W = required mass

M= molar mass

Given chemical reaction is:

3Ca(NO₃)₂ + 2Na₃PO₄ → 6NaNO₃ + Ca₃(PO₄)₂

From the stoichiometry it is clear that:

3 moles of Ca(NO₃)₂ = produce 1 mole of Ca₃(PO₄)₂

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So, 0.5859 moles of Ca(NO₃)₂ = produce 0.5859×1/3 = 0.0196 moles of Ca₃(PO₄)₂

Required mass of Ca₃(PO₄)₂ will be calculated by using moles as:

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Hence, 6.07 grams is the theoretical yield of calcium phosphate.

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2 years ago

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