Why is air considered a fluid?

Which response has both answers correct? Will a precipitate form when 250 mL of 0.33 M Na 2CrO 4 are added to 250 mL of 0.12 M A

olchik [2.2K]

Answer:

A precipitate will form.

[Ag⁺] = 2.8x10⁻⁵M

Explanation:

When Ag⁺ and CrO₄²⁻ are in solution, Ag₂CrO₄(s) is produced thus:

Ag₂CrO₄(s) ⇄ 2 Ag⁺(aq) + CrO₄²⁻(aq)

Ksp is defined as:

Ksp = 1.1x10⁻¹² = [Ag⁺]² [CrO₄²⁻]

Where the concentrations [] are in equilibrium

Reaction quotient, Q, is defined as:

Q = [Ag⁺]² [CrO₄²⁻]

Where the concentrations [] are the actual concentrations

If Q < Ksp, no precipitate will form, if Q >= Ksp, a precipitate will form,

The actual concentrations are -Where 500mL is the total volume of the solution-:

[Ag⁺] = [AgNO₃] = 0.12M ₓ (250mL / 500mL) = 0.06M

[CrO₄²⁻] = [Na₂CrO₄] = 0.33M × (250mL / 500mL) = 0.165M

And Q = [0.06M]² [0.165M] = 5.94x10⁻⁴

As Q > Ksp; a precipitate will form

In equilibrium, some Ag⁺ and some CrO₄⁻ reacts decreasing its concentration until the system reaches equilibrium. Equilibrium concentrations will be:

[Ag⁺] = 0.06M - 2X

[CrO₄²⁻] = 0.165M - X

Where X is defined as the reaction coordinate

Replacing in Ksp expression:

1.1x10⁻¹² = [0.06M - 2X]² [0.165M - X]

Solving for X:

X = 0.165M → False solution. Produce negative concentrations.

X = 0.0299986M

Replacing, equilibrium concentrations are:

[Ag⁺] = 0.06M - 2(0.0299986M)

[CrO₄²⁻] = 0.165M - 0.0299986M

[CrO₄²⁻] = 0.135M

6 0

3 years ago

According to the image, identify the number of neutrons in the most common isotope of aluminum.

wolverine [178]

Answer:

The number of neutron in the Aluminium Isotope is :

B. 14

Explanation:

Isotopes : These are the atoms which have same atomic number but have different mass number.

This image shows the average atomic mass of Al element because it is in decimals.

Atomic mass = 26.98154

(Note : mass number of single isotope can never be in decimals)

It is the average of mass of different isotopes of Al

Major Isotopes of $_{13}^{26.98154}\textrm{Al}$ are :

$_{13}^{26}\textrm{Al}$ ......atomic mass = 26
$_{13}^{27}\textrm{Al}$ .......atomic mass = 27

mass of Al given in image(26.98) is nearly equal to mass of 2nd isotope(27)

mass of $_{13}^{26.98154}\textrm{Al}\ \approx 27$

Now calculate the neutron in $_{13}^{27}\textrm{Al}$

Number of neutron = mass number - atomic number

= 27 - 13

Number of neutron = 14

(Atomic mass is same as mass number)

5 0

3 years ago

When an apple or banana is cut, a chemical reaction with air causes the flesh to turn brown. Placing the fruit in a cold place,

PIT_PIT [208]

Apples turn brown when exposed to air because it undergoes aerial oxidation. Due to this, when the inside of the apple is exposed to the air containing oxygen and water, it turns brown. When apple is uncut, skin of the apple protects it from this process.

If the peeled apple in kept in the refrigerator, the oxidation reaction is greatly slowed down. This is because, rate of chemical reaction decreases with temperature. Hence, in refrigerator it would take several days for it to turn brown.

8 0

3 years ago

Which element is a liquid at STP? (1) bromine (3) francium (2) cesium (4) iodine

ollegr [7]

Among the choices, bromine exists as liquid under standard temperature and pressure conditions. Unlike other diatomic molecules which exist as gases, due to its heavy molecular weight, it exists as solid. Francium and cesium are solids while iodine is gas.Answer is 1.

7 0

4 years ago

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When you break an iron magnet into two pieces, you get ____.

Rudiy27

Answer:

two north poles and two south poles

Explanation:

A single magnet has a north pole and a south pole. If it is broken into two pieces, then each of the two pieces will have a north pole and a south pole.

No matter how many times or into how many pieces a magnet is broken, the resulting pieces will have two poles each.

5 0

3 years ago

Read 2 more answers