Who believed that a grain of sand could be divided indefinitely?

If the ka of a monoprotic weak acid is 1.2 × 10-6, what is the ph of a 0.40 m solution of this acid?

frez [133]

First, we write out a balanced equation.
HA <--> H(+) + A(-)

Next, we create an ICE table

HA <--> H+ + A-
[]i 0.40M 0M 0M
Δ[] -x +x +x
[]f 0.40-x x x

Next, we write out the Ka expression.

Ka = [H+][A-]/[HA]

Ka = x*x/(0.40-x)

However, because Ka is less than 10^-3, we can assume the amount of dissociation is negligible. Thus,

Assume 0.40-x ≈ 0.40

Therefore, 1.2x10^-6 = x^2/0.40

Then we solve for the [H+] concentration, or x

$\sqrt{0.40(1.2*10^{-6})} =x$

x=6.93x10^-4

Next, to find pH we do

pH = -log[H+]

pH = -log[6.93x10^-4]

pH = 3.2

5 0

3 years ago

14. Ionic compound is brittle solid but break

lina2011 [118]

Answer:

A

not sure of answer ndhfhfjfjcjfjfj

7 0

3 years ago

OMG HELP!!!! I SUCK AT SCIENCE

Maksim231197 [3]

Organism are made up of organic molecules consisting of carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus.

The answer is B.

6 0

3 years ago

Read 2 more answers

A mixture is best described as:

Vesna [10]

The conglomeration of two quantities.

Two quantities that go together to become a new identity.

Here are two different definitions you can put in! Hope this helps! Please give brainliest❤️

3 0

3 years ago

32. Explain why carbon shows versatile nature why it forms so many organic compounds.

anyanavicka [17]

Answer:

Carbon is a versatile element and is found in many different chemical compounds, including those found in space. Carbon is versatile because it can form single, double, and triple bonds. It can also form chains, branched chains, and rings when connected to other carbon atoms.

Explanation:

meaning of versatile: capable of or adapted for many different uses, skills, etc. 2 variable or changeable.

The versatile nature of carbon can be best understood with its features such as, tetravalency and catenation. In this section let us learn more about versatility of carbon.

Carbon is a versatile element and is found in many different chemical compounds, including those found in space. Carbon is versatile because it can form single, double, and triple bonds. It can also form chains, branched chains, and rings when connected to other carbon atoms.

The two characteristic features seen in carbon, that is, tetravalency and catenation, put together give rise to a large number of compounds. Many have the same non-carbon atom or group of atoms attached to different carbon chains.

Catenation: The property of forming long chains by self-linking with other carbon atoms to form long chains, rings, double or triple bonds is called catenation.

Isomerism: Compounds with same molecular formula but different structural formula are called isomers. An isomerism commonly seen is due to difference in the arrangement of atoms or groups of atoms & is called structural isomerism. The 4 types of structural isomerism are:

Chain isomerism

Position

Functional

Metamerism

Tetravalency: Carbon has 4 electrons in its valence shell. Energy considerations do not allow it to gain or lose 4 electrons; therefore it forms covalent bonds with other elements to complete its octet. This accounts for its tetravalency and explains its ability to form a variety of compounds.

8 0

3 years ago