Answer:
A. In the Presense of a base
Explanation:
Just took the test from Edgunuity
Phenolphthalein turns pink in color in the presence of a base. Therefore, option A is correct.
What is phenolphthalein and its use?Phenolphthalein is a chemical compound that is often used as an acid-base indicator. It is colorless in acidic solutions and pink or red in basic solutions.
Phenolphthalein is often used in titrations to determine the endpoint of a reaction between an acid and a base. It can also be used as a laxative or in forensic investigations to test for the presence of blood.
Phenolphthalein has a chemical formula of C₂₀H₁₄O₄ and is synthesized by reacting phthalic anhydride with phenol in the presence of a strong acid catalyst. It is also used as a pH indicator. phenolphthalein has been found to have potential health benefits, such as reducing the risk of cancer, improving digestion, and reducing inflammation. Therefore, option A is correct.
Learn more about phenolphthalein, here:
https://brainly.com/question/15211751
#SPJ5
Hydrogen iodide can decompose into hydrogen and iodine gases. 2HI(g) H2(g) I2(g) K for the reaction is 0.016. Of 0.148 atm of HI(g) is sealed in a flask, what is the pressure of each gas when equilibrium is established
Solution :
Given :
Hydrogen iodide decomposes to hydrogen and iodine gas
[tex]$2 HI \ \ \ \Leftrightarrow \ \ \ \ H_2 \ \ \\ + \ \ I_2 $[/tex]
I 0.148 0 0
C -2a +a +a
E 0.148-2a a a
We know
[tex]$k_p=\frac{P(H_2)P(I_2)}{P(HI)^2}$[/tex]
[tex]$0.016=\frac{a^2}{(0.148-2a)^2}$[/tex]
[tex]$0.016^{1/2}=\frac{a}{0.148-2a}$[/tex]
[tex]$0.12649=\frac{a}{0.148-2a}$[/tex]
0.0187 = 1.2529 a
a = 0.0149
Therefore
P(HI) = 0.148 - 2a
= 0.148 - 2(0.0149)
= 0.1182 atm
P([tex]$H_2$[/tex]) = a
= 0.0149 atm
P([tex]$I_2$[/tex]) = a
= 0.0149 atm
Question 4 (10 points)
If a sollition has a pOH of 5.2 the [OH-] of the solution is
оа
6x 10-6 M
Ob
6.3 x 10-6 M
Oc
1.58 x 10-5M
Od
2x10-5M
Answer:
Explanation:
Use the nutrition label to answer the following questions.
16.How much energy is contained in
the six-cookie serving size
recommended on the label?
17.How much energy in joules is provided by eating
six cookies? (1 cal = 4.184 J; ALSO: 1 Calorie = 1
kilocalorie)
Answer:
six cookies?(1 cal _4.184 j; ALSO: 1 Calorie -1 kilocalorie)
An increase in temperature will cause an increase in diffusion rate because Multiple Choice hot molecules get smaller and therefore diffuse faster. the frequency and force of molecular collisions decreases. hot water changes to a solid, so diffusion is easier. hot water is thinner than cold water. the frequency and force of molecular collisions increases.
Answer:
hot water is thinner than cold water.
Explanation:
The rate of diffusion of a substance has a lot to do with the temperature of a body.
Let us take water for instance, cold water has a greater density than hot water. As a result of this, the molecules in cold water are slower when in motion and more sluggish.
On the other hand, the molecules of hot water are quite faster since hot water has a lower density(thinner than cold water).
Thus, an increase in temperature will cause an increase in diffusion rate because hot water is thinner than cold water.
In the coal-gasification process, carbon monoxide is converted to carbon dioxide via the following reaction: CO (g) H2O (g) CO2 (g) H2 (g) In an experiment, 0.35 mol of CO and 0.40 mol of H2O were placed in a 1.00-L reaction vessel. At equilibrium, there were 0.19 mol of CO remaining. Keq at the temperature of the experiment is __________. A) 5.47 B) 1.0 C) 1.78 D) 0.75 E) 0.56
Answer: [tex]K_{eq}[/tex] at the temperature of the experiment is 0.56.
Explanation:
Moles of [tex]CO[/tex] = 0.35 mole
Moles of [tex]H_2O[/tex] = 0.40 mole
Volume of solution = 1.00 L
Initial concentration of [tex]CO[/tex] = [tex]\frac{0.35mol}{1.00L}=0.35M[/tex]
Initial concentration of [tex]H_2O[/tex] = [tex]\frac{0.40mol}{1.00L}=0.40M[/tex]
Equilibrium concentration of [tex]CO[/tex] = [tex]\frac{0.19mol}{1.00L}=0.19M[/tex]
The given balanced equilibrium reaction is,
[tex]CO(g)+H_2O(g)\rightleftharpoons CO_2(g)+H_2(g)[/tex]
Initial conc. 0.35 M 0.40 M 0 M 0M
At eqm. conc. (0.35-x) M (0.40-x) M (x) M (x) M
Given: (0.35-x) = 0.19
x= 0.16 M
The expression for equilibrium constant for this reaction will be,
[tex]K_{eq}=\frac{[CO_2]\times [H_2]}{[CO]\times [H_2O]}[/tex]
Now put all the given values in this expression, we get :
[tex]K_{eq}=\frac{0.16\times 0.16}{(0.35-0.16)\times (0.40-0.16)}[/tex]
[tex]K_{eq}=\frac{0.16\times 0.16}{(0.19)\times (0.24)}=0.56[/tex]
Thus [tex]K_{eq}[/tex] at the temperature of the experiment is 0.56.
For many purposes we can treat butane as an ideal gas at temperatures above its boiling point of . Suppose the pressure on a sample of butane gas at is cut in half. Is it possible to change the temperature of the butane at the same time such that the volume of the gas doesn't change? yes no If you answered yes, calculate the new temperature of the gas. Round your answer to the nearest °C.
Answer:
A. Yes
B. The new temperature of the gas is -116 °C
Note: The question is incomplete. The complete question is given below :
For many purposes we can treat butane C H10) as an ideal gas at temperatures above its boiling point of - 1. °C. Suppose the pressure on a 500 mL sample of butane gas at 41.0°C is cut in half. Iyes Is it possible to change the temperature of the butane at the same time such that the volume of the gas doesn't change? yes no If you answered yes, calculate the new temperature of the gas. Round your answer to the nearest °C.
Explanation:
A. According to the pressure law of gases,for a fixed mass of gas the pressure of a gas is directly proportional to its Kelvin temperature once the volume is kept constant. This means that a change in temperature can bring about a change in pressurein a gas at constant volume.
B. From the pressure law of gasese: P1/T1 = P2/T2
Where initial pressure = P1, final pressure = P2
Initial temperature = T1, final temperature = T2
For the butane gas;
P1 = P
P2 = P/2
T1 = 41°C = (273 + 41 ) K = 314 K
T2 = ?
From the equation, T2 = T1 × P2 / P1
T2 = 314 × P/2 /P
T2 = 157 K
T2 = (157 - 273) °C = -116 °C
Therefore, the new temperature of the gas is -116 °C
14. Simply, explain the role of both the nucleus and the ribosome in protein synthesis.
Answer:
Eukaryotic cells have a true nucleus, which means the cell's DNA is surrounded by a membrane. Therefore, the nucleus houses the cell's DNA and directs the synthesis of proteins and ribosomes, the cellular organelles responsible for protein synthesis.
Ribosomes are the sites in a cell in which protein synthesis takes place. ... Within the ribosome, the rRNA molecules direct the catalytic steps of protein synthesis — the stitching together of amino acids to make a protein molecule.
Students are asked to design an experiment with cookies to demonstrate their understanding of the scientific method. One group has decided to determine the amount of time it will take for a cookie to "dissolve" in a glass of milk.
Which variable would most likely NOT affect the time it takes for the cookie to dissolve?
a) the size of the cup of milk
b) the type of cookie
c) the number of students in the group
d) the temperature of the milk
e) the type of milk
I'm gonna guess E on this one, but I think you should choose either E or A
What is the name of Na
is this correct im just asking because my little brother not sure for his answer
What type of reaction is illustrated?
C3H8 +502 + 3C02 + 4H2O
А
B
decomposition
combustion
single
replacement
Answer:
Combustion
Explanation:
The ionization potential of Be atom is more than expected because it has -
(a) half filled valence p orbitals
(b) fully filled valence s orbitals
(c) both a and b
Answer:
(b) fully filled valence s orbitals
Explanation:
Electron configuration of Be: 1s22s2
2s2 is fully filled
Which equation represents a transmutation?
Answer:
A
Explanation:
edge21
A sample of air was collected on a day when the total atmosphere
pressure was 592 mmHg. The sample contained only oxygen and
nitrogen gas. If the oxygen in the sample had a pressure of 261
mmHg, how much pressure did the nitrogen have?
A. 853 mm Hg
B. 0.206 mm Hg
C. 4.76 mm Hg
D. 331 mm Hg
E. Other________
(Please show me how you did it)
Answer:
D. 331 mm Hg
Explanation:
We can solve this problem by keeping in mind the law of partial pressures, which states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of its components.
In other words:
P oxygen + P nitrogen = Total PWe input the given data:
261 mmHg + P nitrogen = 592 mmHgAnd calculate the pressure of the nitrogen:
P nitrogen = 331 mmHgexplain the process of finishing
Answer:
[Your answer would be in this document of mine below] Thanks :D
Explanation:
Calculate the freezing point of a solution made by dissolving 13 g potassium sulfide in 150 g H2O Kf for water = 1.86 C/m
Answer:
[tex]T_F=-4.4\°C[/tex]
Explanation:
Hello there!
In this case, according to the given information, it is possible for us to calculate the freezing point of an aqueous solution of potassium sulfide by using the following equation:
[tex]T_F=T_{solv}-i*m*Kf[/tex]
In such a way, we firstly calculate the molality of this solution according to:
[tex]m=\frac{\frac{13g}{110.262 g/mol} }{0.150kg} =0.79m[/tex]
Finally, since the Van't Hoff's factor for K2S is 3, the freezing point of the solution turns out to be:
[tex]T_F=0\°C-3*0.79m*1.86\°C/m\\\\T_F=-4.4\°C[/tex]
Regards!
How does carbonic acid work to maintain blood pH? (Select all that apply.) Check All That Apply When blood is too basic, carbonic acid can ionize to bicarbonate and H+ ions, adding H+ ions to the blood. When blood is too basic, carbonic acid can ionize to bicarbonate and H+ ions, adding H+ ions to the blood. When blood becomes too acidic, bicarbonate combines with extra H+ ions to form carbonic acid, removing H+ ions from the blood. When blood becomes too acidic, bicarbonate combines with extra H+ ions to form carbonic acid, removing H+ ions from the blood. Carbonic acid is added to the blood until the pH reaches 7.4. Carbonic acid is added to the blood until the pH reaches 7.4. Carbonic acid always lowers the blood pH to 7.4. Carbonic acid always lowers the blood pH to 7.4. Carbonic acid can raise or lower the pH of blood. Carbonic acid can raise or lower the pH of blood.
Answer:
When blood is too basic, carbonic acid can ionize to bicarbonate and H+ ions, adding H+ ions to the blood.
When blood becomes too acidic, bicarbonate combines with extra H+ ions to form carbonic acid, removing H+ ions from the blood.
Carbonic acid can raise or lower the pH of blood.
Explanation:
A buffer is a solution that resists changes to its pH when small quantities of acids or bases are added to it. The human blood serves as a buffer as it contains a buffer of carbonic acid (H2CO3) and bicarbonate anion (HCO3-) which serves to maintain blood pH between 7.35 and 7.45. Other buffering systems in blood exist such as the Hydrogen ion and oxygen gas which affects oxygen binding to haemoglobin, however the carbonic-acid-bicarbonate buffer is the most important buffer for maintaining acid-base balance in the blood.
A buffer solution is made up of an acid and its conjugate base or a base and its conjugate acid. For carbonic acid-bicarbonate buffer, carbonic acid serves as the acid while bicarbonate serves as the base. When a little quantity of a base as hydroxide ions is added to a buffer, the acid reacts with it and remove it from the solution. On the other hand, when a little quantity of an acid as hydrogen ions are added to a buffer, the conjugate base reacts with it and remove it from the solution, thus keeping the pH of the solution fairly constant.
In the carbonic acid-bicarbonate buffer:
When blood is too basic, carbonic acid can ionize to bicarbonate and H+ ions, adding H+ ions to the blood.
When blood becomes too acidic, bicarbonate combines with extra H+ ions to form carbonic acid, removing H+ ions from the blood.
Thus, carbonic acid can raise or lower the pH of blood.
Carbonic acid work to maintain blood pH as follows:
When blood is too basic, carbonic acid can ionize to bicarbonate and H+ ions, adding H+ ions to the blood.When blood becomes too acidic, bicarbonate combines with extra H+ ions to form carbonic acid, removing H+ ions from the blood.Carbonic acid can raise or lower the pH of blood.WHAT IS BUFFER SOLUTION:A buffer is a solution that resists changes to its pH when small quantities of acids or bases are added to it. A buffer is made up of an acid and its conjugate base or a base and its conjugate acid. Carbonic acid is an example of buffer that contains an acid with it's conjugate base.This means that, carbonic acid works to maintain blood pH as follows:
When blood is too basic, carbonic acid can ionize to bicarbonate and H+ ions, adding H+ ions to the blood.When blood becomes too acidic, bicarbonate combines with extra H+ ions to form carbonic acid, removing H+ ions from the blood.Carbonic acid can raise or lower the pH of blood.Learn more about buffers at: https://brainly.com/question/24188850
The tertiary structure of a protein is a complex arrangement formed as the polypeptide chain folds and twists.
a. True
b. False
Answer:
True
Explanation:
The tertiary structure of a protein is a complex arrangement formed as the polypeptide chain folds and twists.
This folding & twisting of polypeptide chain leading to its complex structure, is true about tertiary structure of protein. It occurs due to different interactions between side chains of amino acids.
During a combustion reaction, 9.00 grams of oxygen reacted with 3.00 grams of CH4.
What is the amount of the leftover reactant?
0.74 grams of methane
0.89 grams of methane
1.22 grams of oxygen
1.45 grams of oxygen
Answer:d
Explanation:
Which of the following is an example of an environmental impact of agriculture?
high use of mineral resources
high use of water
high use of gold, copper, and silver
high use of rock supplies
Answer:
high use of mineral resources
Explanation:
brainliest pls
The lattice-like structure of a metal consists of negative metal ions in a "sea" of electrons.
O True
O False
Answer:
True
Explanation:
How many valance electrons does He need to get to 8
Answer:
Any element in group 18 has eight valence electrons (except for helium, which has a total of just two electrons
______ is the process of change from a liquid to a gas at temperatures below the boiling
point.
Answer:
evaporation is the process
Answer:
EvaporationExplanation:
Evaporation is the process of becoming a vapor. The process of extracting moisture as by heat.
Evaporation is the process of change from a liquid to a gas at temperatures below the boiling point.
Therefore, the final answer is evaporation.
write a story of your life when you were hurted by someone whom you trusted blindly...
Answer:
Sis I think it happened with me but I am not able to remember if u want u can share if it happened with u
Find the % composition for each element in Zinc Chlorate
Answer:
chlorine ~ 30%
zinc ~ 28%
oxygen ~ 41%
Explanation:
Use the scenario to answer the following question. A group of students working in a chemistry lab are planning a procedure to neutralize 10.0mL of 5.0 M hydrochloric acid (strong acid) with 5.0 M potassium hydroxide (strong base). In their procedure they plan on adding an equal volume of the base to the acid. What would be the expected outcome of carrying out this step as planned?
a- The resulting pH will be less than 7 because potassium hydroxide is less concentrated than the hydrochloric acid.
b- The resulting pH will not be able to be determined because the concentrations of the acid and base are not the same.
c- The resulting pH will be greater than 7 because potassium hydroxide is less concentrated than the hydrochloric acid.
d- The resulting pH will be equal to 7 because a strong base will neutralize a strong acid.
Answer:
d- The resulting pH will be equal to 7 because a strong base will neutralize a strong acid.
Explanation:
The reaction between potassium hydroxide and hydrochloric acid of equal volume and equal concentration yields a solution of pH 7 at equivalence point. We must note that KOH is a strong base while HCl is a strong acid. This fact influences the pH of the system at equivalence point.
Owing to the fact that the acid is exactly neutralized by the base; at the equivalence point of such titration, it is expected that hydrogen ions(H+) and hydroxide ions (OH-) must have reacted to form water, this leads to a final pH of 7.
Select the correct answer.
Using this activity chart, which reaction will happen when a piece of copper is placed in a lead nitrate solution?
A.
2Cu + 3Pb(NO3)2 3Cu(NO3)2 + 2Pb
B.
No reaction occurs.
C.
2Cu + 3Pb(NO3)2 2Cu(NO3)2 + 3Pb
D.
3Cu + 3Pb(NO3)2 3Cu(NO3)2 + 3Pb
E.
The answer cannot be determined from the information given.
Answer:
B, No reaction will occur
Explanation:
Copper as compared to lead is less reactive. This is the reason when lead is added to copper nitrate solution, it replaces the copper and itself combines with nitrate to form lead nitrate aqueous solution
Lead + Copper(II) nitrate → Copper + Lead (II) nitrate
The same is not the case when the reaction is revered i.e Cu is added to Pb NO3 solution.
Hence, option B is correct
can someone please do the balanced equation for potassium fluoride?
Answer:
K + F2 = KF
Explanation:
Thats the balancee equation for potassium fluoride. The equation is 2K + F2 → 2KF and the balanced equation is K + F2 = KF
how to make 100 ml of 0.001 mM solution with 0.0405mM solution?
Answer:
Measure 2.47 mL of the stock solution (i.e 0.0405 mM) and dilute it to the 100 mL mark with water
Explanation:
To make 100 mL of 0.001 mM solution from 0.0405mM solution, we need to determine the volume of 0.0405mM solution needed. This can be obtained as follow:
Molarity of stock (M₁) = 0.0405 mM
Volume of diluted (V₂) = 100 mL
Molarity of diluted solution (M₂) = 0.001 mM
Volume of stock solution needed (V₁) =?
M₁V₁ = M₂V₂
0.0405 × V₁ = 0.001 × 100
0.0405 × V₁ = 0.1
Divide both side by 0.0405
V₁ = 0.1 / 0.0405
V₁ = 2.47 mL
Therefore, to make 100 mL of 0.001 mM solution from 0.0405mM solution, measure 2.47 mL of the stock solution (i.e 0.0405 mM) and dilute it to the 100 mL mark with water.
Can you tell me any chemical reaction that occur due to kinetic energy
Answer:
The molecules in gasoline (octane, the chemical formula shown) contain chemical energy. This energy is transformed into kinetic energy that allows a car to race on a racetrack.