Please answer the question

Which substances will make a salt when combined?

BartSMP [9]

Vinegar and tea for sure

3 0

2 years ago

Melts in the system pb-sn exhibit regular solution behavior. at 473°c apb = 0.055 in a liquid solution of xpb = 0.1. calculate t

Masteriza [31]

Given the temperature 746 K and activity of Pb equal to 0.055. The mole fraction of Pb is 0.1. So, the mole fraction of Sn = 0.9.Activity coefficient, γ = 0.055 / 0.1 = 0.55.The expression for w=ln⁡〖γ_Pb x RT〗/(X_Sn^2 )=(-0.5978 x 8.314 J/(mol K ) x 746 K)/(0.9 x 0.9)= -4577.7 J= -4578 J

Now we use the computed value above and new temperature 773 K. The mole fraction of Sn and Pb are 0.5 and 0.5 respectively. Calculate the activity coefficient in the following manner.lnγ_Sn=w/RT X_Pb^2=(-4578 J)/(8.314 J/mol x 773 K) x 0.5 x 0.5= -0.718lnγ_Sn=exp⁡(-0.178)=0.386The activity of Sn= γ_Sn x X_Sn=0.386 x 0.5=0.418
w of the system is -4578 J and the activity of Sn in the liquid solution of xsn at 500 degree Celsius is 0.418

6 0

3 years ago

Please help IM IN HURRY!!!

Vladimir [108]

1.9000 kilogram/cubic meter
8400 kilogram/cubic meter
19300 kilogram/cubic meter

3 0

3 years ago

According to the experimental procedure of Experiment F1, 135 microliters of acetophenone (120.15 g/mol, 1.03 g/mL) was reacted

Delicious77 [7]

Answer: The theoretical yield of 4-nitrochalcone is, $2.13\times 10^2$

Explanation : Given,

Volume of acetophenone = 135 microliters = 135 × 10⁻⁶ L = 0.135 mL

conversion used : (1 microliter = 10⁻⁶ L) and (1 L = 1000 mL)

Density of acetophenone = 1.03 g/mL

Mass of acetophenone = Density × Volume = 1.03 g/mL × 0.135 mL = 0.139 g

Mass of 4-nitrobenzaldehyde = 127 mg = 0.127 g

Conversion used : (1 mg = 0.001 g)

First we have to calculate the moles of acetophenone and 4-nitrobenzaldehyde

$\text{Moles of acetophenone}=\frac{\text{Given mass acetophenone}}{\text{Molar mass acetophenone}}$

$\text{Moles of acetophenone}=\frac{0.139g}{120.15g/mol}=0.00116mol$

and,

$\text{Moles of 4-nitrobenzaldehyde}=\frac{\text{Given mass 4-nitrobenzaldehyde}}{\text{Molar mass 4-nitrobenzaldehyde}}$

$\text{Moles of 4-nitrobenzaldehyde}=\frac{0.127g}{151.12g/mol}=0.000840mol$

Now we have to calculate the limiting and excess reagent.

The balanced chemical equation is:

$C_8H_8O+C_7H_5NO_3\rightarrow C_{15}H_{11}NO_3$

From the balanced reaction we conclude that

As, 1 mole of 4-nitrobenzaldehyde react with 1 mole of acetophenone

So, 0.000840 mole of 4-nitrobenzaldehyde react with 0.000840 mole of acetophenone

From this we conclude that, acetophenone is an excess reagent because the given moles are greater than the required moles and 4-nitrobenzaldehyde is a limiting reagent and it limits the formation of product.

Now we have to calculate the moles of 4-nitrochalcone

From the reaction, we conclude that

As, 1 mole of 4-nitrobenzaldehyde react to give 1 mole of 4-nitrochalcone

So, 0.000840 mole of 4-nitrobenzaldehyde react to give 0.000840 mole of 4-nitrochalcone

Now we have to calculate the mass of 4-nitrochalcone

$\text{ Mass of 4-nitrochalcone}=\text{ Moles of 4-nitrochalcone}\times \text{ Molar mass of 4-nitrochalcone}$

Molar mass of 4-nitrochalcone = 253.25 g/mole

$\text{ Mass of 4-nitrochalcone}=(0.000840moles)\times (253.25g/mole)=0.21273g=212.73mg=2.13\times 10^2mg$

(1 g = 1000 g)

Therefore, the theoretical yield of 4-nitrochalcone is, $2.13\times 10^2mg$

4 0

3 years ago

Aluminium can not rust why .

lisabon 2012 [21]

Answer:

Aluminium Can not rust (Can't rust also meaning Corrode)

Because it's surface is protected by aluminium Oxide which stops the metal below from coming in contact with the air (which contains Oxygen) Unlike rust, which can flake off the surface of iron and steel objects, the layer of aluminium oxide does not flake off.

Corrode

destroy or damage (metal, stone, or other materials) slowly by chemical action.

5 0

2 years ago