A substance that is made up of more than one kind of molecule is called a

How many moles of methanol must be added to 4.50 kg of water to lower its freezing point to -11.0 ∘c? for each mole of solute, t

DochEvi [55]

Given:

Mass of solvent water = 4.50 kg

Freezing point of the solution = -11 C

Freezing point depression constant = 1.86 C/m

To determine:

Moles of methanol to be added

Explanation:

The freezing point depression ΔTf is related to the molality m through the constant kf, as follows:

ΔTf = kf*m

where ΔTf = Freezing point of pure solvent (water) - Freezing pt of solution

ΔTf = 0 C - (-11.0 C) = 11.0 C

m = molality = moles of methanol/kg of water = moles of methanol/4.50 kg

11.0 = 1.86 * moles of methanol/4.50

moles of methanol = 26.613 moles

Ans: Thus around 26.6 moles of methanol should be added to 4.50 kg of water.

3 0

3 years ago

O que são processos físicos de separação das misturas? Dê 3 exemplos

chubhunter [2.5K]

Answer:

Explanation:

The physical methods of separating mixtures are used in sorting a mixture of substances.

It requires no chemical changes occurring between their components and parts in any significant way.

Examples are:

Decantation
Filtration
Sublimation
Magnetism
Centrifugation

The methods simply relies on the physical properties of matter.

8 0

3 years ago

Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas: PCl3(g)+Cl2(g)⇌PCl5(g). A 7.5-L gas vess

Tpy6a [65]

Answer:

The equilibrium constant in terms of concentration that is, $K_c=3.6243\times 10^{3}$ .

Explanation:

$PCl_3(g)+Cl_2(g)\rightleftharpoons PCl_5(g)$

The relation of $K_c\& K_p$ is given by:

$K_p=K_c(RT)^{\Delta n_g}$

$K_p$ = Equilibrium constant in terms of partial pressure.=98.1

$K_c$ = Equilibrium constant in terms of concentration =?

T = temperature at which the equilibrium reaction is taking place.

R = universal gas constant

$\Delta n_g$ = Difference between gaseous moles on product side and reactant side= $n_{g,p}-n_{g.r}=1-2=-1$

$98.1=K_c(RT)^{-1}$

$98.1 =\frac{K_c}{RT}$

$K_c=98.1\times 0.0821 L atm/mol K\times 450 K=3,624.30=3.6243\times 10^{3}$

The equilibrium constant in terms of concentration that is, $K_c=3.6243\times 10^{3}$ .

5 0

3 years ago

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How would I fill out this chart?

Sloan [31]

Answer:

[Top row] - Chemical bonds

[2nd Row L-R] - Force, Ionic, Covalent

[3rd Row L-R] - Atoms, Lost or Gained, Shared

[4th Row L-R] - More stable, Metal and Nonmetal, Nonmetal and Nonmetal

Explanation:

Chemical bonds are a force that hold together atoms in a substance to make compounds more stable.

Chemical bonds include two kinds: Ionic and Covalent.

Ionic in which electrons are lost or gained where attraction is between a Metal and Nonmetal.

Covalent in which electrons are shared where attraction is between a nonmetal and nonmetal.

I have been able to fill the concept map using the correct terms or phrases. The concept map talks about chemical bonds. There are two types of chemical bonds; which ionic bond and covalent bond.

3 0

3 years ago

1. Lab Investigator: Chemical Reactions cannot be used for

Elina [12.6K]

1: viewing any chemical reaction in a laboratory

2: dangerous to look at when it burns & used in photography, fireworks, and flares

3: the product

3 0

3 years ago

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