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3 years ago

How many moles of Fe2O3 are in 209 g of the compound?

Chemistry

1 answer:

Bezzdna [24]3 years ago

7 0

M = 209g
M = 56 * 2 + 16 * 3 = 160 g/mol

n = m/M = 209g / 160 g/mol = 1,30625mol

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What is a non-example of an electrical conductor?

goblinko [34]

Answer: Sulphur, Phosphorus, Wood are non-conductors of electricity due to no presence of free electrons in outermost shell.

Explanation:

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3 years ago

Read 2 more answers

He rate constant of a reaction is 4.55 × 10−5 l/mol·s at 195°c and 8.75 × 10−3 l/mol·s at 258°c. what is the activation energy o

Xelga [282]

Answer : The activation energy of the reaction is, $17.285\times 10^4kJ/mole$

Solution :

The relation between the rate constant the activation energy is,

$\log \frac{K_2}{K_1}=\frac{Ea}{2.303\times R}\times [\frac{1}{T_1}-\frac{1}{T_2}]$

where,

$K_1$ = initial rate constant = $4.55\times 10^{-5}L/mole\text{ s}$

$K_2$ = final rate constant = $8.75\times 10^{-3}L/mole\text{ s}$

$T_1$ = initial temperature = $195^oC=273+195=468K$

$T_2$ = final temperature = $258^oC=273+258=531K$

R = gas constant = 8.314 kJ/moleK

Ea = activation energy

Now put all the given values in the above formula, we get the activation energy.

$\log \frac{8.75\times 10^{-3}L/mole\text{ s}}{4.55\times 10^{-5}L/mole\text{ s}}=\frac{Ea}{2.303\times (8.314kJ/moleK)}\times [\frac{1}{468K}-\frac{1}{531K}]$

$Ea=17.285\times 10^4kJ/mole$

Therefore, the activation energy of the reaction is, $17.285\times 10^4kJ/mole$

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3 years ago

Read 2 more answers

A chemist adds 36.0 g of sodium chloride to 200 g of water at STP and all of the sodium chloride dissolves. What is the solute i

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Answer:

The answer is the Sodium Chloride.

Explanation:

A solute is the minor component in a solution, dissolved in the solvent, and the sodium is being dissolved in water ( or the solvent).

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2 years ago

Fossil A is estimated to be 5,000 years old and fossil B is estimated to be 2,000 year old. If the two fossils had the same amou

elena-14-01-66 [18.8K]

The new fossil i.e, Fossil B (2,000 year old) contains more carbon-14 than the old fossil i.e, Fossil A (5,000 years old ) does.

<h3>What are Fossils ?</h3>

Fossils are the preserved left materials of ancient organisms in trace form.

Fossils are not just the remains of the organism But also the rocks.

Carbon 14 works to analyse the period organic remains that are between 100 years old (minimum) and about 50,000 years old, (maximum).

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Hence,the new fossil Fossil B (2,000 year old) contains more carbon-14 than the older Fossil A (5,000 years old ) does.

Learn more about Fossil here ;

brainly.com/question/19676397

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2 years ago

Calculate molality,molarity and mole fraction of KI if the density of 20%(mass) aqueous KI is 1.202 g/mL

Scorpion4ik [409]

Basis: 1 L of the substance.
(1.202 g/mL) x (1000 mL) = 1202 g
mass solute = (1202 g) x 0.2 = 240.2 g
mass solvent = 1202 g x 0.8 = 961.6 g
moles KI = (240.2 g) x (1 mole / 166 g) = 1.45 moles
moles water = (961.6 g) x (1 mole / 18 g) = 53.42 moles
1. Molality = moles solute / kg solvent
= 1.45 moles / 0.9616 kg = 1.5 m
2. Molarity = moles solute / L solution
= 1.45 moles / 1 L solution = 1.45 M
3. molar mass = mole solute / total moles
= 1.45 moles / (1.45 moles + 53.42 moles) = 0.0264

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4 years ago