HELP!!!
i will mark brainliest ​

pH of solution = 9.661

pH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.

pH = - log [H⁺]

So that the two quantities between pH and [H⁺] are inversely proportional because they are associated with negative values.

pOH=-log[OH⁻]

[tex]\tt pOH=-log[4.583\times 10^{-5}]\\\\pOH=5-log~4.583=4.339[/tex]

pH+pOH=pKw

[tex]\tt pH=14-4.339\\\\pH=9.661[/tex]

Answer:

n = 11.45 mol

Explanation:

Given data:

Number of moles = ?

Volume of gas = 98 L

Pressure = 2.8 atm

temperature = 292 K

Solution:

The given problem will be solve by using general gas equation,

PV = nRT

P= Pressure

V = volume

n = number of moles

R = general gas constant = 0.0821 atm.L/ mol.K  

T = temperature in kelvin

2.8 atm × 98 L = n × 0.0821 atm.L/ mol.K   × 292 K

274.4 atm.L = n ×  23.97atm.L/ mol

n = 274.4 atm.L /23.97atm.L/ mol

n = 11.45 mol

Answer:

In 1869, Friedrich Miescher isolated "nuclein," DNA with associated proteins, from cell nuclei. He was the first to identify DNA as a distinct molecule. Phoebus Levene was an organic chemist in the early 1900's. He is perhaps best known for his incorrect tetranucleotide hypothesis of DNA.

Explanation:

Phoebus Aaron Theodor Levene was born in Sagor in Russia. He grew up in St. Petersburg and studied medicine at the Imperial Military Medical Academy. As a student he worked in the laboratory of his organic chemistry professor where he likely developed an interest in biochemistry.

In 1891, because of growing anti-Semitism in Russia, Levene and his family emigrated to the U.S. They arrived on the symbolic day of July 4. Levene went back to Russia almost immediately to finish his medical degree, but by 1892, he was in New York and practicing medicine on the Lower East Side.

Levene did not give up research. He enrolled as a special student at Columbia University and he split his time between his medical practice and research in the department of physiology. By 1894, he began publishing papers on the chemical structure of sugars. Two years later, Levene received his first appointment as an Associate in the Pathological Institute of the New York State Hospitals. Unfortunately, around this time, Levene contracted tuberculosis and was forced to take time off to recuperate.

Levene used the time between 1896 and 1905 to regain his health and to work with a number of well-known chemists, including Albrecht Kossel and Emil Fischer, the nucleic acid and protein experts of the time. In 1905, Levene was hired by the newly established Rockefeller Institute of Medical Research to head the biochemical laboratory. Levene did most of his nucleic acid work at the Rockefeller and stayed there until his death.

Levene was a cultured man, an art lover and a collector. The walls of his house were lined with either prints and paintings or overflowing bookshelves. Levene was extremely well-read and was fluent in Russian, English, French and German. He also spoke passable Spanish and Italian. His experience, knowledge and his generosity made him a favorite with colleagues and friends. He was also said to be a great teacher, enthusiastic and supportive.

Although mostly remembered now for his incorrect tetranucleotide theory of DNA, Levene published over 700 original papers and articles on the chemical structures of many biochemicals. Levene died in 1940, before the true significance of DNA became clear.

Explanation:

Answer:

200 grams

Explanation:

If the exact same amount is placed on the scale the weight won't change due to the law of conservation of matter.

After the orange has been peeled, the total mass of the orange and peeling will still be 200 grams.

Mass is a physical property of matter which measures the amount of substance in an object. It is measured in grams (g) or kilograms (kg).

According to the law of conservation of mass, when the orange is weighed with the peeling on, the mass of the peeling is included in the measurement.

However, when the orange is peeled, and both the peeling and orange are weighed the mass of the orange and peeling will remain same as 200 grams.

Therefore, the total mass of the orange and peeling after the orange has been peeled is 200 grams.

Learn more about mass here:

https://brainly.com/question/11954533

#SPJ6

The intial temperature : 59.865 °C

Heat added :

Q = m . c . ΔT

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  

∆T = temperature difference, ° C / K  

[tex]\tt 305=94.8\times 0.128\times (85-t_1)\\\\85-t_1=25.135\\\\t_1=59.865^oC[/tex]

The formation of bands in a crystal

Explanation:

- hope that helped :)

Answer:

ummmm

Explanation:

Answer:

B is correct

Explanation:

pls Brainliest

Answer:

Eddie reeling in a fish that he has caught

Explanation:

This tablet insufficient to neutralize the acid in the patient's stomach

Reaction

Al(OH)₃(s) + 3HCl(aq) ⇒ 3 H₂O(l) + AlCl₃(aq)

0.25 g of  Aluminum hydroxide-Al(OH)₃ , mol (MW=78 g/mol) :

[tex]\tt \dfrac{0.25}{78}=0.00321[/tex]

mol HCl : mol Al(OH)₃ = 3 : 1

[tex]\tt mol~HCl=3\times 0.00321=0.00963[/tex]

mass HCl (MW=36,46 g/mol) :

[tex]\tt 0.00963\times 36.46=0.351[/tex]

0.351 < 0.88⇒this tablet insufficient to neutralize the acid

The question is incomplete, the complete question is;

The table above summarizes data given to a student to evaluate the type of change that took place when substance X was mixed with water. The student claimed that the data did not provide enough evidence to determine whether a chemical or physical change took place and that additional tests were needed. Which of the following identifies the best way to gather evidence to support the type of change that occurred when water and Xwere mixed?

A. Measuring the melting point of the mixture of water and X

B. Adding another substance to the mixture of water and X to see whether a solid forms

C Measuring and comparing the masses of the water,  X, and the mixture of water and X

D Measuring the electrical conductivities of X and the mixture of water and X

Answer:

D Measuring the electrical conductivities of X and the mixture of water and X

Explanation:

Unfortunately, I am unable to reproduce the table here. However, from the table,  the temperature of the of the mixture of the solid X and water was 101.6°C. This is above the boiling point of water and way below the temperature of the solid X.

This goes a long way to suggest that there was some kind of interaction between the water and X which accounted for the observed temperature of the system of X in water.

The only way we can be able to confirm if X actually dissolved in water is to measure the conductivity of the water. dissolved solids increase the conductivity of water.

The statement which identifies the best way to gather evidence to support the type of change that  occurred when water and X were mixed is:

According to the given question, we are asked to show the statement which identifies the best way to gather evidence to support the type of change that  occurred when water and X were mixed. \

As a result of this, we can see that from the complete question, there is a need to note the temperature of the solution which is 101.6°C and then to measure the conductivity of the water to know for sure the type of change that occured.

Therefore, the correct answer is option D

Read more here:

https://brainly.com/question/18384031

Answer:

D

Explanation:

cracks from temperature changes is a type of physical weathering often known as freezing and thawing

Answer:

protons, neutrons, electrons

Explanation:

the three main subatomic particles that form an atom protons,neutrons and electrons. the center of the atom is called the nucleus.

Answer:

[tex]{\boxed {\sf Protons: +1, Nucleus}}[/tex]

[tex]\boxed {\sf Neutrons: 0, Nucleus}}[/tex]

[tex]\boxed {\sf Electrons: -1, Surrounding \ the \ Nucleus}}[/tex]

Explanation:

There are 3 subatomic particles: protons, neutrons, and electrons.

Protons

Charge

Location

Neutrons

Charge

Location

Electrons

Charge

Location

Answer:

Electrons occupy the regions around the nucleus(energy levels) while protons and neutrons are found in the nucleus

Answer

ice wedging .................

Answer:

ice wedging

Explanation:

Answer:

An ionic compound is named first by its cation and then by its anion. The cation has the same name as its element. For example, K+1 is called the potassium ion, just as K is called the potassium atom.

Answer:

Acids are named based on their anion — the ion attached to the hydrogen. In simple binary acids, one ion is attached to hydrogen. Names for such acids consist of the prefix “hydro-“, the first syllable of the anion, and the suffix “-ic”. Complex acid compounds have oxygen in them.

Answer:

B. Electron pairs repelling each other push atoms apart

Explanation:

The VESPR theory explains molecular shape by suggesting that electron pairs repelling each other push atoms apart.

If an atom is bonded to two or more other kinds of atoms as in many covalent molecules and ions, the shape of the system is determined by the geometry of the bonds around the central atom.

Explanation:

As you cool a matter to absolute zero, their kinetic energy reduces significantly and the molecules slows down and begins to aggregate together.

Answer:

they represent liquid state of matter.

Answer:

they state liquid state of matter .

hope it is helpful to you

Answer: it’s B for edge !

Explanation: took the test

Answer:

Simple distillation

Answer: chill google dat junk sis lol but i thought i could help i just dont wanna get u da wrong answer su

Explanation:

Answer:

The kind of ion is X2+ ( where the ion is formed as a result of the loss of two valence electrons)

Explanation:

The ratio of ions of the element X to the phosphate ions is 3 to 2

So what we have as formula of these will be;

X3(PO4)2

Generally we have the phosphate ion formula as; PO4^3-

So for this formula above to be possible then the element x will have a formula of its ion X2+

Answer:

c

Explanation:

Answer:

the answer of the question is C

Answer:

The element hydrogen has the simplest atoms, each with just one proton and one electron. The proton forms the nucleus, while the electron orbits around it.

Explanation:

Answer:

Assuming pressure is held constant,the question reduces to a ratio and proportion type of question where;

At constant pressure,

21.0ft³-55.0°F

11.0fy³=11.0ft³/21.0ft³×55°F

The temperature is 28.809°F≈29°F

29°F is the temperature of the helium if the volume of the balloon decreases to 11.0ft³.

Temperature expresses hotness and coldness or a measure of the average kinetic energy of the atoms or molecules in the system.

Assuming pressure is held constant, the question reduces to a ratio and proportion type of question where;

At constant pressure,

21.0ft³- 55.0°F

11.0fy³ = 11.0ft³ ÷ 21.0ft³ × 55°F

The temperature is 28.809°F ≈ 29°F

Hence, 29°F is the temperature of the helium if the volume of the balloon decreases to 11.0ft³.

Learn more about temperature here:

brainly.com/question/28004147

#SPJ2

Answer: a 900 milliliter (ml) pitcher of orange juice at 20 degrees Celsius ( oC)

Explanation:

Thermal energy is the energy possessed by an object by virtue of its temperature. The hotter the substance, the more its molecules vibrate, and therefore the higher its thermal energy.

Thermal energy refers to the sum of kinetic, potential, vibrational ,electronic and rotational energies of the object.

For bodies at same temperature, the body with more molecules will have more thermal energy due to more collisions.

Answer:

[tex]\boxed {\boxed {\sf B. \ 22 \ grams}}[/tex]

Explanation:

We need to use the formula for heat of vaporization.

[tex]Q=H_{vap}*m[/tex]

Identify the variables.

[tex]H_{vap}=2260 \ J/g\\Q=50,000 \ J \\[/tex]

Substitute the values into the formula.

[tex]50,000 \ J=2260 \ J/g*m[/tex]

We want to find the mass. We must isolate the variable, m.

m is being multiplied by 2260 J/g. The inverse operation of multiplication is division. Divide both sides by 2260 J/g.

[tex]\frac{50,000 \ J}{2260 \ J/g} =\frac{2260 \ J/g*m}{2260 \ J/g}[/tex]

[tex]\frac{50,000 \ J}{2260 \ J/g} =m[/tex]

Divide. Note that the Joules (J) will cancel each other out.

[tex]\frac{50,000 \ }{2260 \ g} =m[/tex]

[tex]22.1238938 \ g =m[/tex]

Round to the nearest whole number. The 1 in the tenth place tells us to leave the number as is.

[tex]22 \ g \approx m[/tex]

The mass is about 22 grams, so choice B is correct.

Answer:

The blades of the fan are spinning

An air flow is felt

The fan warms up

Explanation:

I've never seen sparks on a fan and there is no light produced. Don't over think the question.