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3 years ago

Classify correct or incorrect.

Chemistry

2 answers:

olga_2 [115]3 years ago

6 0

Answer:

1. Incorrect, it occurs in gases as well or generally in fluids.

2. Correct.

3. Incorrect.

Explanation:

Hello,

1. Convection, is a heat transport phenomena which occurs when a fluid transfers energy in the form of heat to a surface or vice-versa, in such a way, it occurs fluid, say, in both gases and liquids.

2. In this case, radiation is a heat transfer phenomena which occurs by thermal waves transferring the heat; such waves are generated by a hot body which it is said to irradiate the waves by cause of its inner temperature, therefore, as it could be surrounded by a colder space, heat is transferred. As a result of the high temperature, all substances could radiate heat.

3. In this case, it is widely known that normal temperature is between 20 and 25 ºC while the body's inner temperature is about 37 ºC for our organism to work properly. In such a way, those temperatures are different.

Best regards.

Musya8 [376]3 years ago

5 0

1. incorrect also gases
2. correct
3. incorrect

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3 years ago

What ion depolarizes the membrane when it diffuses into the axon of a neuron?

Agata [3.3K]

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3 years ago

Calculate ΔH o rxn for the following: CH4(g) + Cl2(g) → CCl4(l) + HCl(g)[unbalanced] ΔH o f [CH4(g)] = −74.87 kJ/mol ΔH o f [CCl

anzhelika [568]

Answer: ΔH for the reaction is -277.4 kJ

Explanation:

The balanced chemical reaction is,

$CH_4(g)+Cl_2(g)\rightarrow CCl_4(l)+HCl(g)$

The expression for enthalpy change is,

$\Delta H=\sum [n\times \Delta H(products)]-\sum [n\times \Delta H(reactant)]$

$\Delta H=[(n_{CCl_4}\times \Delta H_{CCl_4})+(n_{HCl}\times B.E_{HCl}) ]-[(n_{CH_4}\times \Delta H_{CH_4})+n_{Cl_2}\times \Delta H_{Cl_2}]$

where,

n = number of moles

Now put all the given values in this expression, we get

$\Delta H=[(1\times -139)+(1\times -92.31) ]-[(1\times -74.87)+(1\times 121.0]$

$\Delta H=-277.4kJ$

Therefore, the enthalpy change for this reaction is, -277.4 kJ

4 0

2 years ago

A 0.055 mol sample of formaldehyde vapor, CH2O, was placed in a heated 500 mL vessel and some of it decomposed. The reaction is

Elis [28]

Answer:

Kc for this reaction is 0.06825

Explanation:

Step 1: Data given

Number of moles formaldehyde CH2O = 0.055 moles

Volume = 500 mL = 0.500 L

At equilibrium, the CH2O(g) concentration = 0.051 mol

Step 2: The balanced equation

CH2O <=> H2 + CO

Step 3: Calculate the initial concentrations

Concentration = moles / volume

[CH2O] = 0.055 moles . 0.500 L

[CH2O] = 0.11 M

[H2] = 0M

[CO] = 0M

Step 4: The concentration at the equilibrium

[CH2O] = 0.11 - X M = 0.051 M

[H2] = XM

[CO] = XM

[CH2O] = 0.11 - X M = 0.051 M

X = 0.11 - 0.051 = 0.059

[H2] = XM = 0.059 M

[CO] = XM = 0.059 M

Step 5: Calculate Kc

Kc = [H2][CO]/[CHO]

Kc = (0.059 * 0.059) / 0.051

Kc = 0.06825

Kc for this reaction is 0.06825

7 0

3 years ago

In order to promote the common ion effect, the concentration of the common ion must first:_____.

Svet_ta [14]

We need to increase the concentration of common ion first, in order to promote the common ion effect

<h3>What is the Common ion effect?</h3>

It is an effect that suppresses the dissociation of salt due to the addition of another salt having common ions.

For example, a saturated solution of silver chloride in equilibrium has Ag⁺ and Cl⁻ . Sodium Chloride is added to the solution and has a common ion Cl⁻. As a result, the equilibrium shifts to the left to form more silver chloride. Thus, solubility of AgCl decreases.

The Equilibrium law states that if a process is in equilibrium and is subjected to a change

in temperature,
pressure,
the concentration of reactant or product,

then the equilibrium shifts in a particular direction, according to the condition.

Thus, an increase in the concentration of common ion promotes the common ion effect.

Learn more about common ion effect:

brainly.com/question/23684003

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1 year ago