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4 years ago

A 125-g sample of Fe2O3 contains how many moles?

Chemistry

1 answer:

dem82 [27]4 years ago

4 0

Answer:

To find the number of moles we must first calculate the molar mass( M) of Fe2O3

Molar mass = mass / number of moles

M(Fe2O3) = (55.8 ×2) + (16×3)

= 111.6 + 48

= 159.6 g/mol

number of moles = mass / molar mass

= 125g/159.6g/mol

= 0.783mol

Hope this helps

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3 years ago

Which would be the best way to represent the concentration of a 1. 75 M K2CrO4 solution? 1. 75% K2CrO4 [K2CrO4] (K2CrO4) K2CrO4,

tekilochka [14]

The amount of the solute present in the given solution is called the concentration. The best way to represent the concentration of the solution is $\rm [K_{2}CrO_{4}].$

<h3>What is molar concentration?</h3>

Molar concentration is the molarity of the solution that is the measure of the concentration of the solute dissolved in the solution.

The formula for calculating molar concentration is given as,

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brainly.com/question/1532164

8 0

2 years ago

If 200.4g of water is mixed with 101.42g of salt the mass of the final solution would be reported as

d1i1m1o1n [39]

Answer:

301.8 g

Explanation:

We prepare a solution with 200.4 g of water (solvent) and 101.42 g of salt (solute). The mass of the solution is equal to the sum of the mass of the solvent and the mass of the solute.

m(solution) = m(solute) + m(solvent)

m(solution) = 200.4 g + 101.42 g

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3 years ago

How many moles are in 20 grams of O₂ gas?

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2 years ago

Use one of your experimentally determined values of k, the activation energy you determined, and the Arrhenius equation to calcu

stealth61 [152]

Answer:

Explanation:

Use one of your experimentally determined values of k, the activation energy you determined, and the Arrhenius equation to calculate the value of the rate constant at 25 °C. Alternatively, you can simply extrapolate the straight line plot of ln(k) vs. 1/T in your notebook to 1/298 , read off the value of ln(k), and determine the value of k. Please put your answer in scientific notation. slope=-12070, Ea=100kJ/mol, k= 0.000717(45C), 0.00284(55C), 0.00492(65C), 0.0165(75C), 0.0396(85C)

Explanation;

According to Arrhenius equation:

i.e. ln(k2/k1) = -Ea/R (1/T2 - 1/T1)

Where, k1 = 0.000717, T1 = 45 oC = (45+273) K = 318 K

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6 0

3 years ago