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3 years ago

What is the concentration of hydroxide ions in pure water at 30.0 ∘C, of Kw at this temperature is 1.47x10-14?

Chemistry

1 answer:

klio [65]3 years ago

7 0

Answer:

[OH⁻] = 1.21×10⁻⁷

Explanation:

Water dissociates in the solution as:

H₂O ⇔ H⁺ + OH⁻

For pure water, the concentration of [H⁺] and [OH⁻] are equal.

Kw is defined as the product of the active concentration of H⁺ and OH⁻ furnished by the water.

So,

Kw = [H⁺] [OH⁻]

Given that, at 30.0 °C, the Kw is 1.47×10⁻¹⁴

So,

Kw = [H⁺] [OH⁻]

As stated above, [H⁺] = [OH⁻]

1.47×10⁻¹⁴ = [OH⁻]²

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Hii pls helpnme to write out the ionic equation

Oxana [17]

Answer:

CO32-(aq) + 2H+(aq) → CO2(g) + H2O(l)

Explanation:

According to this question, sodium carbonate reacts with sulfuric acid to form aqueous sodium sulfate, carbon dioxide and water. The balanced chemical equation is as follows:

Na2CO3(aq) + H2SO4(aq) → Na2SO4(aq) + CO2(g) + H2O(l)

- Next, split compounds that are aqueous into ions.

2Na+(aq) + CO32-(aq) + 2H+(aq) + SO42-(aq) → 2Na+(aq) + SO42-(aq) + CO2(g) + H2O(l)

- Next, we cancel out the spectator ions, which are ions that remain the same in the reactants and products side of a chemical reaction. The spectator ions in this equation are 2Na+(aq) and SO42-(aq).

CO32-(aq) + 2H+(aq) → CO2(g) + H2O(l)

- Hence, the balanced ionic equation is as follows:

CO32-(aq) + 2H+(aq) → CO2(g) + H2O(l)

3 0

3 years ago

Atoms of the same element can have different forms; for example, carbon-12 and carbon-14.

cricket20 [7]

A carbon-12 atom has 6 protons (6P) and 6 neutrons (6N). But some types of carbon have more than six neutrons. We call forms of elements that have a different number of neutrons, isotopes. For example, carbon-14 is a radioactive isotope of carbon that has six protons and eight neutrons in its nucleus.
Hope that helps

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3 years ago

(HELP ME ASAP!)

slega [8]

A) Ca(OH)2 + CO2 —> CaCO3 + H2O

B) when Ca(OH)2 is reacted with CO2, the CaCO3 produced is a precipitate which turns the solution milky

8 0

3 years ago

g Consider an ideal atomic gas in a cylinder. The upper part of the cylinder is a moveable piston of negligible weight. The heig

kumpel [21]

A cylindrical weight with a mass of 3 kg is dropped onto the piston from a height of 10 m. The entropy of the gas is 1.18 J/K and the change in the entropy of the environment is -1.18 J/K.

A cylindrical weight with a mass (m) of 3 kg is dropped, that is, its initial velocity (u) is 0 m/s and travels 10 m (s). Assuming the acceleration (a) is that of gravity (9.8 m/s²). We can calculate the velocity (v) of the weight in the instant prior to the collision with the piston using the following kinematic equation.

$v^{2} = u^{2} + 2as = 2 (9.8 m/s^{2} ) (10m) \\\\v = 14 m/s$

The object with a mass of 3 kg collides with the piston at 14 m/s, The kinetic energy (K) of the object at that moment is:

$K = \frac{1}{2} m v^{2} = \frac{1}{2} (3kg) (14m/s)^{2} = 294 J$

The kinetic energy of the weight is completely converted into heat transferred into the gas cylinder. Thus, Q = 294 J.

Given all the process is at 250 K (T), we can calculate the change of entropy of the gas using the following expression.

$\Delta S_{gas} = \frac{Q}{T} = \frac{294 J}{250K} = 1.18 J/K$

The change in the entropy of the environment, has the same value but opposite sign than the change in the entropy of the gas. Thus, $\Delta S_{env} = -1.18 J/K$

Learn more: brainly.com/question/22655760

6 0

2 years ago

The force of 75 N must overcome in order to get the truck to start moving. What type of friction must be overcome?

Tamiku [17]

Answer:

Static Friction.

Explanation:

Friction is the force that resists the relative motion between the surfaces sliding against each other.

Static friction is friction between objects that are not in relative motion with each other.

The coefficient of static friction, typically denoted as μs,

Static friction arises due to surface roughness( relative term)

The static friction force can be overcome by an applied maximum force

F max = μs x N

N= normal force

Any force smaller than F max attempting to slide one surface over the other is opposed by a frictional force of equal magnitude and opposite direction.

Any force larger than F max overcomes the force of static friction and causes sliding to occur.

This maximum force is sometimes called the limiting value also. Here that value is 75 N.

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3 years ago