# What happened if you put the Elodea leaf cells in a solution of 0.5% NaCl,1.8% NaCl and 0.9%NaCl?

36,754 questions, page 319
1. ## Chem 1LB

When 0.678 g of Ca metal is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 11.0C is observed. Assume the solution's final volume is 200.0 mL, the density is 1.00 g/mL, and the heat capacity is 4.184 J/gC. (Note: Pay attention to

asked by Libit on February 21, 2010
2. ## chemistry

When 0.712 g of Ca metal is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 116C is observed. Assume the solution's final volume is 200.0 mL, the density is 1.00 g/mL, and the heat capacity is 4.184 J/gC. (Note: Pay attention to significant

asked by wilson on May 18, 2009
3. ## Chem 1LB

When 0.678 g of Ca metal is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 11.0C is observed. Assume the solution's final volume is 200.0 mL, the density is 1.00 g/mL, and the heat capacity is 4.184 J/gC. (Note: Pay attention to

asked by Libit on February 21, 2010
4. ## Economics

3. Peter owns just his car and has £2,500 in cash. The car is worth £7,500. The probability that the car will be stolen (and never recovered) is 0.1. If his vNM utility function is two times the square root of his wealth, what is the maximum amount he

asked by Susan on December 5, 2009
5. ## chemistry

A sample of solid monoprotic acid with molar mass equal to 169.7 g/mol was titrated with 0.1599M sodium hydroxide solution. Calculate the mass in grms fo acid to be used if the volume of NAOH to be used is 25ml. My calculation 0.1599 x 0.025L = 0.00399

asked by Fai on August 4, 2012
6. ## chemistry HELP!!

Reaction Rate = -(1/2) [d(H2O2)/dt] = [d(O2)/ dt] Using 25 mL of a 0.2 M hydrogen peroxide solution, the following results are obtained from the equation above: 8.62 mL of gas is collected in 120 seconds. (Assume 760 Torr = 1 atm) Room temperature is 25

asked by Aaron on September 21, 2015
7. ## Chemistry

Lake VIda is an enormous hypersaline lake that lies under 19 m of ice in the Dry Valleys region of Antartica. The freezing point of this water is approximately -15.0 degrees C, owing to the fact that it is many times as salty as typical saltwater.

asked by Shea on October 18, 2010
8. ## chemistry

This equation decribes oxidation of acidified solution of sodium oxalate(Na2C2O4) by potassium permanganate(KMnO4): 5 C2O4^2- + 2Mn04^- + 16H2SO4 to produce 10Co2 + 2Mn^2- + 16HSO4^- + 8H2O. what volume of 0.127M sodium oxalate in sulphuric acid will react

asked by Temmick on February 6, 2014
9. ## criminology

Can someone tell me a policy that is in effect that relates to trait theories? Determine how far sound travels in 55 minutes. Express your answer in feet. You may use 760 mph as the speed of sound.Do I divide,add,subtract or multiply. Check out this site:

asked by Kg on May 18, 2007
10. ## Science help.

1. The ___ is the outer, thinnest layer of your skin, which houses sweat pores. (1 point) epidermis dermis fatty layer hair 2. One of the purposes of sweat glands is to release waste products, such as water and _____. (1 point) blood dirt sugar salt 3.

asked by Someone on March 14, 2013
11. ## French

I am not sure that I have the correct answers to these questions, I have been looking at this for ages. I have typed the paragraph and will put the questions underneath (I have done some of the other questions myself but these two I am struggling with)

asked by Nix66 on September 14, 2014
12. ## chemistry

Which of the following solutes dissolved in 1000 g of water would provide a solution with the LOWEST freezing point? A. 0.030 mole urea, CO(NH2)2 B. 0.030 mole acetic acid, CH3COOH C. 0.030 mole ammonium nitrate, NH4NO3 D. 0.030 mole calcium sulfate, CaSO4

asked by random on June 20, 2010
13. ## Intermidiate Algebra

Andrew factored the expression -12x^3-28x^2-3x as -4x (3x^2-7x+9). But when Melissa applied the distributive law and multiplied out -4x (3x^2-7x+9), she got -12x^3+28x^2-36x; thus, Andrew’s solution does not appear to check. Why is that? Please help

asked by Elisa on June 19, 2011
14. ## HCS/335

Are laws and regulations the problem or the solution in addressing ethical problems? Explain. What would be an alternative? I got this from ms.sue and i need to strech it into 300 words? can anyone help me? Laws and regulations help in guiding human

asked by Tina.....HELP PLZ on February 2, 2011
15. ## CHEMISTY HELP!!!

A professor found that there are 109 drops of glacial acetic acid in 2.00 mL. Calculate the number of drops of glacial acetic acid, HC2H3O2 required to make 155 ml of 0.25 M acetic acid solution Can anyone walk me through the steps and provide an answer.

asked by Sam on October 21, 2011
16. ## math 117

Living in or near a metropolitan area has some advantages. Entertainment opportunities are almost endless in a major city. Events occur almost every night, from sporting events to the symphony. Tickets to these events are not available long and can often

asked by Tina on October 6, 2010
17. ## physics

an airplane is diving at a speed of 300 km/h and the angle betweent he plane's dive path and the vertical is 50 degrees. The plane launches a rocket which lands at 750m horizontally from beneath the launch point. a) find the flight time of the rocket and

asked by nix on November 2, 2006
18. ## English

Read the following quote from Betty Bonham Lies’s retelling of the myth of Orpheus and Eurydice. When Orpheus made music, all the world stopped to listen. Wild beasts drew near him, so entranced they put aside their fierceness. Trees gathered around to

asked by Mike on May 18, 2016
19. ## Physics

if it takes 726 watts of power to move a mass 36 meters in 14 seeconds, what is the mass? i really need like, step by step help please? asap. thanks, michelle . physics - bobpursley, Saturday, November 20, 2010 at 4:06pm power= work/time=

asked by michelle quendarsv on November 20, 2010
20. ## spanish

i need to write this in spanish A few months ago my teeth started hurting a lot. I went to the dentist's office to get them checked. When I arrived, the dentist told me that they were very crooked. He said he was going to give me some shots and then put

asked by y912f on June 11, 2009
21. ## Elem. Ed.

I posted this question yesterday,and am still confused. Can someone please help? Which is one of the best ways teachers can help chldren deal with stress: 1.Applying proper behavior management techniques. (or) 2. Providing soothing and relaxing hands-on

asked by Keisha on April 12, 2007
22. ## English

Could someone help me write a thesis statement for the following topic: "Our school should be free of all weapons including the guns carried by a police officer." So far this is what i have for a thesis statment. "Although having police officers in our

asked by Matthew on May 7, 2009
23. ## Inclusive Language—Quoting from Biased Material

The mayors and their wives were invited on a tour of the state buildings. --Thats the question but I don't get it because nothings stated. their spouses would be better. Some of the mayors might be wives. If that sentence is a quotation, then you must use

asked by Kim on February 9, 2007
24. ## Literacy

Which of the following sets of Dewey Decimal call numbers is in the correct order? A. 813.54 C782A, 813.54 C78A, 813.54 C780B, 813.54 C781D B. 813.54 C78A, 813.54 C780B, 813.54 C781D, 813.54 C782A C. 813.54 C781D, 813.54 C78A, 813.54 C782A, 813.54 C780B D.

asked by Heather on January 17, 2012
25. ## Math 222

This is the second part to my first question A quadratic function Graph the function g(x) = 4 − x2, and state the domain and range. Solution We plot enough points to get the correct shape of the graph. See Fig. 11.10 for the graph. The domain is

asked by Tika-PLEASE HELP on May 4, 2015
26. ## Math 222

This is the second part to my first question A quadratic function Graph the function g(x) = 4 − x2, and state the domain and range. Solution We plot enough points to get the correct shape of the graph. See Fig. 11.10 for the graph. The domain is

asked by Tika-PLEASE HELP on May 4, 2015
27. ## chemistry

propanoic acid ch3ch2cooh is a weak acid which has a value for dissociation content of ka = 6.3 x 10^-6 calculate the pH of an aqueous solution of propanoic acid containing 37 g of propanoic acid per litre. i'm stumbled on this one.. i calculated that the

asked by rick on July 27, 2010
28. ## English

Order the sentences: In the following three paragraphs, the sentences have been jumbled out of order. Put the sentences in order to make a well-written cohesive paragraph. Number each line by the order it should be placed, and place it in the box below.

asked by Sam on March 30, 2019
29. ## Chemistry II

Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent. When 3.28 g of quinine is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is

asked by Sam on July 17, 2012
30. ## AP Chemistry

i'm having trouble balancing the redox reaction for the iodine clock lab. The redox reaction inovlves a hydrogen sulfite ion and iodate ion in an acidified solution. i have the final balanced equation, 5 HSO3 + 2 IO3 ---> I2 + 5SO4 + H20 + 3H but i'm

asked by Jake on March 13, 2008
31. ## physics

A rod with length L and mass m stand on a frictionless table. a ball with mass m and speed u cimped perpendicular to the rod a distance x from the bottom of the rod and sticks to it. what is the angular velocity of the rod+ball after the collison? I need

asked by david on January 27, 2015
32. ## math

a rectangular tank,50cm long and 30cm wide,contains water upto a height of 9 cm.a box of dimensions 25cm,25cm,20cm is not placed in the tank so that its square faces rest on the bottom of the tank. the quantity of the water that must be poured into the

asked by madhulika on October 28, 2015
33. ## chemistry

Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent. When 2.50 g of quinine is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is

asked by sam on March 25, 2014
34. ## Chemistry

calculate the 0.4M molarity of ammonia From data given, how to prepare 200ml of 0.4M ammonia solution 25%. From previous study, i found that the calculation is M1V1=M2V2 From formula, Initial concentration (M1)is 910000mg/L, vOlume of beaker (V2)=200ml,

asked by Merlina_Lyn on January 30, 2013
35. ## chem

a 275mL sample of vapor in equilibrium with 1-propylamine at 25C is removed and dissolved in 0.500L of H20. For 1-propalamine, Kb=3.72*10^-4 and the vapor pressure at 25C is 215 torr. (a)What should be the pH of the aqueous solution? (b) How many mg of

asked by leanna on March 22, 2011
36. ## Math

1. Graph the points A ( -5,0) B ( -4, 3) and C ( 0, -4) A B C D 2. Identify the quadrant in which (3, -6) lies A II B IV C I D III 3. Determine which ordered pair is a solution of y = 2x - 3 A ( -2, 7) B ( 0, 3) C ( -4, -11 D ( 5, -7 5. Graph the linear

asked by Justin on March 23, 2017
37. ## cylinder word problem

Caitlin enjoys italian ices with her friends. The place scoops the ices into a cylindrical cup that has a radius of 3 cm and a height of 8 cm. each ice is topped off with a half scoop. Each scoop has a radius of 3 cm. What is the total amount of ice that

asked by andrea on March 24, 2015
38. ## Chemistry

A weak acid with an initial pH of 3.2 was titrated with a strong base. 15 mL of 0.1 M NaOH was added to the acid to reach the equivalence point at a pH of 8.6. What would you expect the approximate pH of the analyte to be after the first 5 mL of 0.1 M NaOH

asked by Jason on June 15, 2018
39. ## science

Calculate the volume of solution that has a vapour pressure of 25.8 mbar and contains 200.3 g of galactose, C6H12O6, at a temperature of 22.0 °C. The vapour pressure of pure water at 22 °C is 26.40 mbar, the density of water is 1.00 g mL-1, and assume no

asked by Jane Smith on June 5, 2015
40. ## computers

You have been hired by a small company to network six computers in one small office that will be connected directly to the Internet. The company president wants a cost effective solution that will prevent hackers from accessing the gaining access to the

asked by Anonymous on March 4, 2010
41. ## English

I left out the following questions. Can you please check them, too? 1) My father works as a lorry driver and I helped him unloading goods from his lorry. 2) I spent the first part of my holiday studying for my make-up exams in Physics and Maths. Then I

asked by Henry2 on September 12, 2011
42. ## math

6x sq.-5x-1=0 use the equation of the squre if u want to solve it. use the quadratic formula Please read: http://en.wikipedia.org/wiki/Quadratic_equation Or http://mathworld.wolfram.com/QuadraticFormula.html how can i do fractons and i need some advised

asked by John on May 23, 2007
43. ## CHEM

could someone please explain how to work out the highest fhydride and the highest flouride of ununhexium ,if the valance is 6 UUHF6 AND UUH6 ,I THOUGHT IT WOULD HAVE BEEN UUH2COULD SOMEONE EXPLAIN MANY THANKS hi Jill i sent you a message are you able to

asked by jill on January 31, 2007

Jeremy is in Grade 8. He has a paper route and wants to save for his college education. He determines that he has $100 per month to put into an account at 6%/a compounded monthly. How much will he have at the end of five years for his college education? n asked by Alicia on January 17, 2011 45. ## Chem II PCl5 dissociates according to the reaction: PCl5(g) ↔ PCl3(g) + Cl2(g). One mole of PCl5 was placed in one liter of solution. When equilibrium was established, 0.5 mole of PCl5 remained in the mixture. What is the equilibrium constant for this reaction? asked by Sam on February 29, 2012 46. ## algebra Joseph always throws change into a can and takes it out every two weeks. This time it is all nickels and dimes. There are six times as many dimes as nickels, and the value of the dimes is$4.95 more than the value of the nickels. How many nickels and dimes

asked by aj on April 22, 2012
47. ## Chemistry

What is the element whose 2+ cation's highest energy electron has the following set of quantum numbers, n=5, l=2, ml=1, and m.s=+1/2 for its highest energy electron? I know, based on the quantum numbers, that its referring to a 5d sublevel. Is it Ba? How

asked by Ceamus Angelina on April 6, 2018
48. ## Chemistry

Which forms the more alkaline solution and why? Al2O3; B2O3; CO2 or SiO2 Al2O3 and SiO2 are not water-soluble. CO2 forms the weak acid H2CO3, in water. What does that leave you with?

asked by Vic on August 8, 2007
49. ## Maths Algebra

A steamer goes downstream and covers the distance between two ports in 4 hours while it covers the same distance upstream in 5 hours.If the speed of the stream is 2 km/h.Find the speed of steamer in still water.Check your solution.

asked by Vivek on August 19, 2016
50. ## Chemistry-II (Percent Composition)

1. Identify the percent composition of sodium carbonate. 2. Determine the percent composition of calcium in calcium carbonate. Pls. help me... my prob is that there is something in the solution that bothers me.. pls.kindly show me how to do.. i'll thank u

asked by jezzaD. on January 23, 2013
51. ## math

A box A contains 9 red balls and 1 white ball. A box B contain 8 red balls and 1 white ball. A ball is to be taken at random from box A and put into box B. Then a ball is to be taken at random from box B. Find the probability that this ball from box B is

asked by Cindy on January 5, 2010

Four products are processed sequentially on three machines. The following table gives the pertinent data of the problem. Manufacturing time (hr) per unit Machine Cost per hr ($) Product 1 Product 2 Product 3 Product4 Capacity (hr) 1 10 2 3 4 2 500 2 5 3 2 asked by nk on November 14, 2016 53. ## For Hannah Re http://www.jiskha.com/display.cgi?id=1369225544 Sorry to have caused confusion for you Hannah. In your original post, you had 3 different problems, the first two were "volume" questions. When I did the third one, which was simply finding an area, I asked by Reiny on May 22, 2013 54. ## chemistry A 0.4515 g sample of pure CaCO3 was transferred to a 500 mL volumetric flask and dissolved using 6M HCl then diluted to volume. A 50.00 mL aliquot was transferred to a 250mL Erlenmeyer flask and the pH adjusted. Calmagite was used as an indicator the asked by darren on February 15, 2012 55. ## Linear Programming Maximize P = 16x + 80y subject to these constraints: 2x + 20y ≤ 430 4x + 70y ≤ 1400 8x + 30y ≤ 980 10x + 10y ≤ 1000 4x + 30y ≤ 700 x ≥ 0, y ≥ 0 Maximum value for P = ?. This value of P occurs when x = ? and y = ? If u1, u2, u3, u4, and u5 asked by JP on September 20, 2010 56. ## Math Maximize P = 16x + 80y subject to these constraints: 2x + 20y ≤ 430 4x + 70y ≤ 1400 8x + 30y ≤ 980 10x + 10y ≤ 1000 4x + 30y ≤ 700 x ≥ 0, y ≥ 0 Maximum value for P = ?. This value of P occurs when x = ? and y = ? If u1, u2, u3, u4, and u5 asked by John on September 20, 2010 57. ## academic honesty (answers included) What do you think of when you hear the term academic honesty? How does knowing the difference among original ideas, common knowledge, and plagiarism help you stay honest when you write an academic paper? What are some of the consequences of not being asked by scooby on January 13, 2010 58. ## History ***= my answers 1.) Shared government power between the states and federal government is known as Limited government Popular sovereignty Federalism*** None of the above. 2.) The government has only as much authority as the people give it is known as asked by mstv on November 19, 2015 59. ## Accounting I need some help with this question… It is confusing me… I have parts of it done but would like someone to help explain it to me. A truck was purchased on January 2 at a cost of$60,000. It’s expected to be used for five years and to have a residual

asked by sady on July 24, 2012
60. ## English

Thank you very much. The sentences you checked are part of an exercise in which students are asked to put the verbs (from the active) into the passive voice. Do you think they are OK or shall I change sentence number 5? 1) He's going to do the washing-up

asked by Henry1 on May 15, 2011
61. ## Chemistry

the corrosion of iron is similar to the reactions that occur in an electrochemical cell. Oxidation and reduction occur at separate places on the metal and the circuit is completed by an electrolyte in solution one possible corrosion is Fe(s)+O2(g) + H2O(l)

asked by ryan on November 30, 2011
62. ## CHEM HELP

Nicotinic acid (niacin) is a monoprotic acid with the formula HC6H4NO2. A solution that is 0.012M in nicotinic acid has a pH of 3.39 at 25*C. What is the acid-ionization constant, Ka and pKa for this acid at 25*C? is the ionization equation: HC6H4NO2+

asked by Sandra on March 24, 2009
63. ## economics 11

The demand and supply schedules for milk are as follows: Price Quantity Demanded Quantity Supplied 10 0 125 8 20 95 6 40 65 4 60 35 2 80 5 a. On the same graph, draw the demand and supply curves. What does the demand curve for a product describe? What does

asked by Anonymous on September 9, 2014
64. ## maths

the annual demand for a product is 800 unit a unit price of the product is #0.02. If the ordering cost is # and the holding cost is 10% of the unit price ; determine the I) EOQ in the units ii) total variable cost iii) number of orders per annum. plz what

asked by carman on May 4, 2019
65. ## Chemistry

91.7g of HCL solution was added to the calorimeter and brought to a constant temp. Then 0.5278g of MgO was added and the Temp rose from 25.65C to 32.60C and held steady. Then 0.0185g of Mg was added and the temp again rose from 30.35C to 32.20C. Calculate

asked by Laura on January 12, 2009
66. ## Chemistry

Sally is goint to determine the quantity of MgSO4 by titrating the Mg2+ ions using EDTA. What is the concentration of Mg2+ (in mmol/L) in the sample if it takes 22.9 mL of EDTA solution with concentration of 0.01108 mol/L to titrate 50.00 mL of the sample

asked by Cody on March 14, 2010
67. ## Chemistry

You have synthesized a substance from aqueous solution that has a melting point of 152 °C. A pure authentic sample of the intended product has a melting point of 154 °C. The most likely explanation for the difference in melting temperature is that the

asked by Lynne on June 11, 2010
68. ## chemistry

During lab, you are provided with a stock antibody solution (Ab) that has a concentration of 400 μg/μl. For lab, it is necessary make the following dilutions (Fill in the blanks): 5μL of Stock Ab + 195μL of buffer to make a 1:____ dilution at

asked by gabrielle on September 13, 2011
69. ## English

1. I am into sports. (What is the meaning of this sentence?) 2. Exercise is good for the health. 2-1. Exercise is good for health. 2-2. Exercise is good for your health. 2-3. Exercise does good for people. (Are all correct?) 3. Our athletic meet took place

asked by John on November 24, 2008

Five (5) years ago, you bought a house for $171,000, with a down payment of$30,000, which meant you took out a loan for $141,000. Your interest rate was 5.75% fixed. You would like to pay more on your loan. You check your bank statement and find the asked by Anonymous on March 2, 2013 71. ## math Five (5) years ago, you bought a house for$171,000, with a down payment of $30,000, which meant you took out a loan for$141,000. Your interest rate was 5.75% fixed. You would like to pay more on your loan. You check your bank statement and find the

asked by mary on February 22, 2013
72. ## algebra

Five (5) years ago, you bought a house for $171,000, with a down payment of$30,000, which meant you took out a loan for \$141,000. Your interest rate was 5.75% fixed. You would like to pay more on your loan. You check your bank statement and find the

asked by mary on February 22, 2013
73. ## Physics

The Speed of train is reduced from 60km/h at the same time as it travels a distance of 450 m, If the retardation is uniform , find how much further it will travel (approx) before coming to rest? Answer is 30m but how? See my solution , i solved it in two

asked by Shahab Mirza on October 28, 2014
74. ## Reading

2. Read the following excerpt from “All Together Now”: What can parents do? We can put our faith in young people as a positive force. I have yet to find a racist baby. Babies come into the world as blank as slates and, with their beautiful innocence,

asked by Anna Jones on January 17, 2014
75. ## Spanish

Answer the following questions about demonstrative adjectives. Answer whether the noun modified is singular or plural. Then fill in the blank with the correct demonstrative adjective in Spanish. 1. They prefer that restaurant. Prefieren -------restaurante.

asked by Aubrey on May 21, 2007
76. ## Chemistry

A beaker with 200 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.100 M. A student adds 6.40 mL of a 0.400 \it M \rm HCl solution to the beaker. How much will the pH

asked by Bobby on March 29, 2011
77. ## chemistry

Analysis of a compound gave 39.50% C, 2.20% H, and 58.30% Cl. When 0.855 g of this solid was dissolved in 7.50 g of napthalene, the solution had a freezing point of 78.0° C. The pure solvent freezes at 80.0° C; its molal freezing point constant is 6.8°

asked by Chris on September 14, 2010
78. ## Chemistry

Bromine can be added to limonene to create a brominated compound. When 613 mg of limonene and 3.5 mL of a 10% (v/v) solution of Br2 in dichloromethane (a solvent) are combined, 959 mg of the product is isolated. Calculate the percent yield for this

asked by Kate on March 2, 2010
79. ## Algebra 2

1. Solve the following for x. 3-(x+(-4))= 2x-6+5x I figured that the answer is no solution. Is this correct? I have been working with my friend on this next problem and neither of us know which is correct. 2. Solve for r. I=P(1+rt) The first answer is

asked by Christian on August 30, 2007
80. ## Chemistry

What is the vapor pressure of a solution composed of 3.0 moles benzene (vapor pressure 12.1 kPa) & 1 mole chloroform (vapor pressure 25.2 kPa)

asked by Anonymous on January 15, 2008
81. ## ALGEBRA -- long division

Find each solution using long division. Show your work. Show that x + 1 is NOT a factor of... 2x^3 + x^2 - 11x - 30. Show that x - 3 IS a factor of 2x^3 - 11x^2 - 11x^2 + 12x + 9.

asked by Stephanie on September 25, 2008
82. ## math

Consider these two tables for Line 1 and Line 2. Line 1: x | y 0 1 3 4 Line 2: x | y 0 0 2 4 (a) Graph Line 1 (already did this) (b) Graph Line 2 on the same graph (already did this) (c) What is the solution to the system? Use graphing to solve. Explain

asked by Bella on March 10, 2017
83. ## Algebra

That is not what the ? is asking. The ? is asking about how to get the quotient function, not the composite as you solved for. Can you please show us how to get the quotient function solution? Thanks! I need to find the Quotient Function of the following:

asked by Rachale on June 14, 2009
84. ## Chemistry

A student needs 1.0L of buffer solution with a PH =10.0 .She selects the HCO3^- >CO3^2- buffer system. The K(HCO3^-) =5.6x10^-11 . what is the [HCO3^-]/[CO3^2-]ratio for the buffer?

asked by samson on October 23, 2011
85. ## chem

I need help classifying these as physical or chemical changes! 1. sodium metal exposed to air turns dark gray. 2. steam in a test tube condenses to moisture. 3. baking soda in vinegar releases bubbles. 4. water dissolves in vinegar to give a solution. 5.

asked by Emily Grossman on March 1, 2011
86. ## chemistry

A student found that there are 115 drops of glacial acetic acid in 2.00 mL. Calculate the number of drops of glacial acetic acid, HC2H3O2 required to make 225 mL of 0.1 M acetic acid solution

asked by Erin on October 16, 2011
87. ## Biochemistry

How do you calculate the free energy change for the acetyl phospahate hydrolysis in a solution of 2 mM acetate, 2 mM phosphate and 3 nM acetyl phosphate. The standard state free energy of hydolysis of acetyl phosphate is /\G = -42.3 kJ/mol.

asked by nicki on October 4, 2010
88. ## Chem

Methylaime, CH3NH2. If a 0.100 mol/L solution of methyamine has a pH of 11.80, calculate the ionization constant for the weak base. What is an ionization constant. Is it just K? This is what I did so far: 11.80 = -log (concentration of h3o+) 10^-11.80 =

asked by Lena on July 23, 2009
89. ## chemistry

A silver wire is immersed in a solution containing ions of CU2 + what is expected in this situation? A) no reaction occurs. b) The silver wire is oxidized. c) Copper is deposited on the silver wire. D) The ions Cu2 + are reduced.

asked by kelly on July 13, 2018
90. ## Calculus

Find the specific solution of the differential equation dy/dx = 4y/x^2 with condition y(−4) = e. y equals negative 1 minus 4 divided by x

asked by nan on March 11, 2016
91. ## Education

Hello, I need help I have to make my own personal code of Ethics following the NAEYC guidelies and also a statement of commitment as I would have to be able to follow for the classrooms and field experience. I am trying to find somewhere where I can look

asked by Chris on January 21, 2007
92. ## Science Fair

Hi, my question is are part 1,2, and 3 different ways you can do the project? There are three parts. Each part should take less than 1 hour. In Part 1, you will stare at a colored object for various amounts of time, then measure how long it takes for the

asked by Unknown on October 23, 2012
93. ## chemistry

An unknown was prepared with the concentration of 0.000630 M. A Beer's Law plot was prepared using the absorbance values from standard solutions of ASA and a line drawn through all the points passed through the origin with a slope of 1550.2 M–1. The

asked by john on January 27, 2008
94. ## chemistry

An unknown was prepared with the concentration of 0.000630 M. A Beer's Law plot was prepared using the absorbance values from standard solutions of ASA and a line drawn through all the points passed through the origin with a slope of 1550.2 M–1. The

asked by Michael on January 27, 2008
95. ## Literature

I need help in with writing my introduction paragraph I have started with Literary devices are use by authors to make their readers think and relate to their topics. Greek literature is a great example of this. The meaning of these symbols is affected by

asked by Dr. Rose on April 6, 2008
96. ## AE is this correct?

determine the teachercertification/licensure requirements for the state you would like to teach in. I picked wisconsin and i put this...... Initial In-State Teaching or Pupil Services - PI-1602-IS Graduates of Wisconsin educator preparation programs only.

asked by scooby91320002 on March 6, 2009
97. ## Algebra 2

Can someone check my answers. Write the following equations in standard form. 1) x^2 - 2x + y^2 + 4y = 11 answer: (x-1)^2 + (y+2)^2 = 16 2) 4x^2 + 24x - y + 34 = 0 answer: y = 4(x-3)^2 + 2 3) The graph of which equation is a circle? A. 5x^2 + 10x = 9 +

asked by Troy on April 7, 2008
98. ## psy - revise

Psychotherapy is a method used to treat mental and emotional disorders. People that suffer from these disorders talk to a mental health professional about their concerns and other related issues through a series of scheduled sessions. This method can also

asked by rose - Ms. Sue on May 29, 2008
99. ## Math - Steve

I posted this question yesterday that you answered, so thank you, but how do I put this in my calculator to get this answer? If the exponential equation of best fit is y= 2.9046(1.9798)^x, when will the population be more than 13 million? How would I

asked by Carly on December 3, 2017