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2 years ago

9

How many moles of al does 13.49 g of al represent?

1 answer:

Harlamova29_29 [7]2 years ago

7 0

Use equation
number of moles= sample mass/molar mass

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At a constant pressure and amount of gas, how are temperature and volume related?

RSB [31]

The volume is directly proportional to the absolute temperature so the answer is A.

7 0

2 years ago

Consider the following reaction: CH3OH(g)⇌CO(g)+2H2(g) Part A Calculate ΔG for this reaction at 25 ∘C under the following condit

kati45 [8]

<u>Answer:</u> The $\Delta G$ of the reaction at given temperature is -12.964 kJ/mol.

<u>Explanation:</u>

For the given chemical reaction:

$CH_3OH(g)\rightleftharpoons CO(g)+2H_2(g)$

The expression of $K_p$ for the given reaction:

$K_p=\frac{(p_{CO})\times (p_{H_2}^2)}{p_{CH_3OH}}$

We are given:

$p_{CO}=0.140atm\\p_{H_2}=0.180atm\\p_{CH_3OH}=0.850atm$

Putting values in above equation, we get:

$K_p=\frac{(0.140)\times (0.180)^2}{0.850}\\\\K_p=5.34\times 10^{-3}$

To calculate the Gibbs free energy of the reaction, we use the equation:

$\Delta G=\Delta G^o+RT\ln K_p$

where,

$\Delta G$ = Gibbs' free energy of the reaction = ?

$\Delta G^o$ = Standard gibbs' free energy change of the reaction = 0 J (at equilibrium)

R = Gas constant = $8.314J/K mol$

T = Temperature = $25^oC=[25+273]K=298K$

$K_p$ = equilibrium constant in terms of partial pressure = $5.34\times 10^{-3}$

Putting values in above equation, we get:

$\Delta G=0+(8.314J/K.mol\times 298K\times \ln(5.34\times 10^{-3}))\\\\\Delta G=-12963.96J/mol=-12.964kJ/mol$

Hence, the $\Delta G$ of the reaction at given temperature is -12.964 kJ/mol.

5 0

3 years ago

How many moles are in 2.0 grams of Na?

lisov135 [29]

Answer:

46

Explanation:

Sodium metal has a molar mass of

22.99

3 0

2 years ago

A sample of gas (24.2 g) initially at 4.00 atm was compressed from 8.00 l to 2.00 l at constant temperature. after the compressi

FinnZ [79.3K]

Answer: 16 atm
Explanation:
P1V1 = P2V2
P2 = P1V1/V2
=4 atm x 8.00 L/2.00L = 16 atm

5 0

2 years ago

1. Marisa determined the melting point of a substance to be 24.5C. Find the percent error of her measurement if the actual melti

USPshnik [31]

Answer:

$\%\ Error = 21.5\%$

Explanation:

Given

$Measured = 24.5$

$Actual = 31.2$

Required

Determine the percentage error

First, we need to determine the difference in the measurement

$Difference = |Actual - Measured|$

$Difference = |31.2 - 24.5|$

$Difference = |6.7|$

$Difference = 6.7$

The percentage error is calculated as thus:

$\%\ Error = \frac{Difference * 100\%}{Actual}$

$\%\ Error = \frac{6.7 * 100\%}{31.2}$

$\%\ Error = \frac{670\%}{31.2}$

$\%\ Error = 21.4743589744\%$

$\%\ Error = 21.5\%$ <em>approximated</em>

6 0

3 years ago