# why was it important to cover each beaker with a piece of aluminum foil?

15,221 questions, page 10
1. ## chemistry

You have 53 g of aluminum at25 degrees C. How much heat must be added to raise its temperature to 139 degrees C? Assume the specific heat of aluminum is 903 J/kg · degrees C. Answer in units of J

2. ## physics

A brass ring of diameter 10.00 cm at 22.2°C is heated and slipped over an aluminum rod of diameter 10.01 cm at 22.2°C. Assume the average coefficients of linear expansion are constant. (b) What if the aluminum rod were 9.16 cm in diameter?

asked by niti on April 5, 2014
3. ## physics

A firecracker in a coconut blows the coconut into three pieces. Two pieces of equal mass fly off south and west, perpendicular to each other, at 25 m/s. The third piece has twice the mass as the other two. 1. What is the speed of the third piece? 2. What

asked by Levin Need help for test! on November 5, 2014
4. ## Chem

Precision, Accuracy, and Percent Error: _______________________________________ Suppose a student measures the volume of an aluminum block three times and records the following data: 8.42 cm^3, 8.41 cm^3, and 8.40 cm^3. The accepted volume of the aluminum

asked by Paige on September 18, 2015
5. ## math

A piece of wood is divided in 3 pieces in the ratio 3:4:2. The length of the longest piece is 72. Calculate the length of the piece of wood.

asked by Patricia on January 25, 2017
6. ## Math

A wire 32 cm long is cut into two pieces. The longer piece is 6 cm longer than the shorter piece. What is the length of the shorter piece?

asked by Angii on February 13, 2017
7. ## Physics

The melting point of aluminum is 660°C, its latent heat of fusion is 4.00 × 105 J/kg, and its specific heat is 900 J/kg • K. If 300 kJ of heat are added to 442 g of aluminum at 100°C, what is the final state of the system? That is, how much is liquid,

asked by MB on March 10, 2016
8. ## math

If you need 240 oz of paint to cover 1200 in. How much paint do you need to cover 2000 in.?

asked by Lindsey on February 24, 2012
9. ## Chemistry

What happens to the mass of a beaker of water with a teaspoon of sugar in it measured on a balance pan compared to a teaspoon of sugar and a beaker of water separated on a balance pan? does the mass increase, decrease or stay the same? and why?

asked by Sydney on January 18, 2011
10. ## Chemistry

Given that the vapor pressure of water is 17.54 torr at 20 C, calculate the vapor-pressure lowering of aqueous solutions that are 2.40 m in (a) sucrose, C12H22O11, and (b) aluminum chloride. Assume 100% dissociation for electrolytes. Sucrose Delta P = __

asked by David on February 19, 2012
11. ## Physics HELP!!

a). What is the wavelengh of a 2.54MHz ultrasound wave travelling through aluminum?(the speed of sound in aluminum is 6420 m/s) b). What frequency of electromagnetic wave would have the same wavelength as the ultrasound wave above?

asked by joane on November 21, 2012
12. ## Physics

Johnny was in a closed door meeting and suddenly his phone rung. His immediate response was to cover his cellphone with his hand and then asked to be excused. Why did he cover his phone with his hand? PS: Please explain it briefly but the thought is very

asked by Laica on November 11, 2017
13. ## math,correction

Directions:Multiply Problem: ((x)/(3)+(3)/(4)) ((3x)/(4)-(3)/(5)) so the answer for it i got: ((20x^2+20x-36)/(80)) I worked it and I have what you have EXCEPT 29x instead of 20x. If you can't find the error, post your work and we can help you find it.

asked by Jasmine20 on January 24, 2007
14. ## Easy Math for you Hard for Me

Some children were seated around a large round table. They pass around a box of candy containing 25 pieces. Bob took the first piece. Each child takes a piece of candy as the box is passed around. Bob also gets the last piece, and he may have more than the

asked by Melthea on September 6, 2007

Some children were seated around a large round table. They pass around a box of candy containing 25 pieces. Bob took the first piece. Each child takes a piece of candy as the box is passed around. Bob also gets the last piece, and he may have more than the

asked by Melthea on September 6, 2007
16. ## Chem

I did an experiment were I added some water and KHP into a beaker and phenophalene [sp?]. It was a titration lab. We slowly added calciuum hydroxide into the beaker and waited till the solution turned into a faint pink. The question is asking me to find

asked by Lena on July 22, 2009
17. ## Maths

A drinking straw of length 21cm is cut into 3 pieces the length of the first piece is x cm the second piece is 3 cm shorter than the first piece the third is twice as long as the first piece state term of x to represent the sum of of the length {2} write

asked by RAHEIM on August 18, 2012
18. ## Algebra

A board 5 feet long is cut into two pieces such that the length of one piece is two-thirds of the length of the other piece. Find the length of the shorter piece of board

asked by Chanelle on January 29, 2013
19. ## Math

A mower can cover 7.2 acres per hour. A newer model can cover 8.1 acres per hour. What percent more can the newer model cover?

asked by Renee on November 1, 2012
20. ## physics

A 60ft aluminum at 60 degree farenhiet to 100 degree farenhiet. Whats is the final length of the aluminum?

asked by marvin on March 3, 2016
21. ## Chem

When 30.0 grams of aluminum reacts with HCl how many grams of aluminum chloride are formed? Al = HCl yields AlCl3 + H 2

asked by Amber on December 15, 2011
22. ## Intermediate Algebra

Using the foil method,multiply....(2/5t-1)(3/5+1)

asked by sherry on April 3, 2012
23. ## science

why does a wadded up foil sink

asked by lora on July 7, 2012
24. ## Algebra

asked by Jake on March 27, 2011
25. ## algebra

using foil method x^2 + (x+1)+(x+3)^2 =38 then combine

asked by nicky on August 15, 2008
26. ## math

200 ft of foil for \$6.24 per pound

27. ## maTH

x(x - 1)(x + 1). Would you FOIL the parenthesis first or multiply the x by (x-1) first?

asked by Anonymous on January 11, 2010
28. ## Algebra

Solve using FOIL (y-2) (3y3-5y+7)

asked by billy on March 17, 2014
29. ## college algebra

would this be foil method? If so how do I solve. x-1 x-5 = x+3 x+4

asked by dot on February 17, 2011
30. ## Physics

An object with total mass mtotal = 15.8 kg is sitting at rest when it explodes into three pieces. One piece with mass m1 = 4.5 kg moves up and to the left at an angle of θ1 = 18° above the –x axis with a speed of v1 = 27.6 m/s. A second piece with mass

31. ## chemistry

How many aluminum atoms are in 3.78 g\rm g of aluminum?

asked by ANTHONY on October 20, 2014

need help on a lab here are the results Mass of empty beaker and glass rod(62.62) Mass of beaker, glass rod, hydrated copper sulfate(66.02) Mass of beaker, glass rod and anhydrous copper sulfate(65.04) Mass of hydrated copper sulfate(3.4) Mass of anhydrous

asked by Katherine on December 1, 2014
33. ## Chemistry

i need help on a lab here are the results Mass of empty beaker and glass rod(62.62) Mass of beaker, glass rod, hydrated copper sulfate(66.02) Mass of beaker, glass rod and anhydrous copper sulfate(65.04) Mass of hydrated copper sulfate(3.4) Mass of

asked by MINNIE on December 1, 2014
34. ## Physics

A hardworking ant must supply 0.00955 N to pull a small piece of fruit at constant velocity over a distance of 8.60 cm up a small hill to the entrance of the colony. If the coefficient of kinetic friction between the piece of fruit and the 16.2° sloped

asked by Anonymous on November 4, 2013
35. ## Chemistry

To a beaker containing 200 mL of a solution of CuSO4 was added 10.0g of magnesium metal. When the reaction was complete, a mixture of Mg and Cu having a mass of 14.50g remained in the beaker. Calculate the molarity of the original CuSO4 solution. I

asked by Kay on February 17, 2012
36. ## Chemistry

Hello, I am having trouble with a question from my chem lab. Here is my data Weight of empty crucible and cover = 21.113 g Weight of crucible, cover, MgO and Mg3N2 = 21.906 g Weight of crucible, cover, MgOand addition of H2O and heat =21.909 g The change

asked by Steve on September 23, 2008
37. ## Chem

The specific heat capacity of aluminum is .89 J/y degrees C. How much heat is required to change the temp of 1500g aluminum pan from 25 degrees C to 100 degrees C?

asked by Emily on October 17, 2010
38. ## Chem

The specific heat capacity of aluminum is .89 J/y degrees C. How much heat is required to change the temp of 1500g aluminum pan from 25 degrees C to 100 degrees C?

asked by Emily on October 17, 2010
39. ## TO MS SUE SCIENCE HELP

These are my last 2 questions i need help on.... 1. to determine the density of an irregularly shaped object, a student immersed the object in 21.2 ml of water in a graduated cylinder, causing the level of the water to rise to 27.8 ml. If the object had a

asked by SPIKE on December 14, 2012
40. ## chemisrty

what is the balanced equation for thereaction of aluminum selenide with water including the physical states reactants and products im given hydrogen selenide prepared by reacting aluminum selenide with water other product solid aluminum hydroxide please

asked by donald on February 1, 2007
41. ## chemistry

hey drbob222 do you think you could help me out with this lab. Lab: Electrolytic Cells Purpose: The purpose of this experiment is to test the method of stoichiometry in cells. Materials: balance steel can tin electrode power source wire lead (x2) tin (II)

asked by unknown on April 14, 2008
42. ## Science

1. You observe two beakers containing clear liquid and ice cubes. In the first beaker, the ice cubes are floating. In the second, the ice cubes are on the bottom of the beaker. Write a hypothesis to explain the difference in your observations about the two

asked by Crystal on September 18, 2012
43. ## Physics

Jenny measured the temperature of the water in a beaker, set the beaker aside, and then measured the temperature again after an hour. If the initial temperature of the water was 30°C and the final temperature was 20°C, which of the following could be the

asked by Meka on August 23, 2012
44. ## Spanish

Which statement is accurate? A. Fútbol is more important that béisbol in all Spanish­speaking countries. B. Béisbol is more important than fútbol in México. C. Béisbol is more important than fútbol in Cuba, Puerto Rico, and la República

asked by Reed on December 19, 2017
45. ## chemistry

Two solutions were prepared. The first was a 0.672 M solution of aluminum hydroxide and the second was a 0.405 M sulfuric acid solution. 1.) If a total of 500 mL of aluminum hydroxide solution was prepared, how many grams of the solute (AL(OH)3) would have

asked by Jordan on May 7, 2014
46. ## english

Please help me to correct my anserw below.thank you Petroleum, or crude oil, is one of the world's (1) _____ natural resources. Plastics, synthetic fibres, and (2) _____ chemicals are produced from petroleum. It is also used to make lubricants and waxes.

asked by jessie on April 27, 2017
47. ## Chemistry

A beaker with 100 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 6.10 mL of a 0.260 M HCl solution to the beaker. How much will the pH change?

asked by Sandra on March 18, 2011
48. ## chemisrty

have been asked to write how i got this equation but i cant put it in words can you help me Al2 Se3 +6 H2O ==> 2Al (OH)3 +3H2Se i can do this but like i said putting it into words i just cannot make it coherant The answer you should give is you found it on

asked by donald on January 31, 2007
49. ## chem

how to set up or approach these 1. Calculate the mass in grams of iodine (I2) that will react completely with 48.9 g of aluminum (Al) to form aluminum iodide (AlI3). Do I need to find the mass as a whole for the entire compound, then convert? 2. The

asked by hannah on February 9, 2009
50. ## Social studies

Directions; With your partner research events that occurred during each time period below. Use this information to make your illustrated timeline on separate blank paper. Your timeline might cover the entire 1800–1950 period or a part of that time. my

asked by Stella on May 3, 2017
51. ## Chemistry

Question: you have a clear, colorless aqueous sample in a beaker that contains either CO2^-2(aq) or C^-1(aq) or a mixture of both ions. the following aqueous reagents are available: NaCl, HNO3, and AgNO3. describe a procedure that will allow the

asked by Anonymous on May 12, 2009
52. ## Chemistry

How many moles of aluminum chloride can be produced if you start with 8 moles of aluminum and 9 moles of chlorine?

asked by Nina on May 24, 2011
53. ## Math

A ten-foot-long board is cut into three pieces. The second piece is half as long as the first. The third piece is 4 feet longer than the second. How long is the first piece? Answer: 2 3/4 feet If f(x)=2x2+1/2x-4, what is f(-1/2)? Answer: -15/4 **I am

asked by Jess on November 14, 2016
54. ## Physics/Chem

A cube of aluminum 24.0 cm on each side is cooled from 128 °C to 20 °C. If the energy removed from the aluminum cube were added to a copper cube of the same size at 30 °C, what would be the final temperature of the copper cube?(ρAl = 2700 kg/m³;

asked by Jeff Kinka on July 1, 2016
55. ## Chemistry

What is the empirical formula for aluminium selenide? What is the common oxidation state of aluminum? Combine that information with the valency for selenium that you came up with in the previous question to come up with the formula for aluminum selenide.

asked by sarah on February 19, 2007
56. ## Physics

The pressure at a depth of 300 m in the ocean exceeds sea-level atmospheric pressure by 3.03 kPa. By how much does the volume of a 0.2-m3 aluminum object contract when lowered to this depth in the ocean? The bulk modulus of aluminum is 7 x 10^10 Pa.

asked by Zainal on May 29, 2014
57. ## social studies

what is texas important important service industries I don't know what you mean by "important". Major employers of service type jobs are fast foods, cleaning, police, maintenance and repair organizations (automobile, aircraft, building), and state and

asked by vicky on May 18, 2007
58. ## Chemistry

A sample of aluminum oxide, Al2O3(s), contains 8.29*10^25 total atoms. Calculate the amount in moles of aluminum oxide in the sample. Hint: This is a two-step problem. Calculate the number of formula units first.

asked by lg on April 6, 2013
59. ## Math

Sophie measured a piece of paper to be 21.7 cm by 28.5 cm. The piece of paper is actually 21.6 cm by 28.4 cm. Determine the amount of square centimeters in the area of the piece of paper using Sophie's measurements.(I got 618.45 sq cm) Determine the number

asked by Angie on May 29, 2009
60. ## Math

A 12-ft. board is cut into 2 pieces so that one piece is 4 feet longer than 3 times the shorter piece. If the shorter piece is x feet long, find the lengths of both pieces.

asked by Denise on April 21, 2016
61. ## Structures and Functions of the Human Body

Heart disease is the leading cause of death in the U.S. Imagine you are teaching a class on heart health. Identify three main topics you would cover in your class. Then, choose one of the topics and explain in 1-2 paragraphs why it is important to the

asked by Tina on August 18, 2010
62. ## chemistry

What mass of aluminum hydroxide will be produced when 0.460 grams of aluminum sulfide react with water? How many grams of hydrogen sulfide are produced, according to the following equaton? Al2S3 + H20 -------> Al(OH)3 + H2S

asked by john on January 19, 2012
63. ## Chemistry

A galvanic cell is made with aluminum and zinc electrodes. (For Ag^+(aq)+(e^-)--->Ag(s), E=0.80 V and for Cu^2+(aq)+(2e^-)--->Cu(aq), E=0.34 V) Write the standard cell notation for this cell. Wouldn't it be silly to use the potentials for copper and silver

asked by Aubrey on June 17, 2007
64. ## Chemistry

Aluminum metal crystallizes in a face centered cubic lattice. If each Al atom has a radius of 1.43 A what is the density of aluminum metal? I'm not sure how to go about this. I know that eventually I will use V=l^3, but I'm not sure how to get there. I

65. ## math

What does FOIL stand for in Math Like PEMDAS

asked by cody on October 15, 2009
66. ## math

solve for x 3x^2 + 2x - 5 = 0 you foil it and get: (x - 1)(3x + 5) but i don't know what to do from here. please please pleasee help.

asked by sarah on September 2, 2008
67. ## Algebra

Use the FOIL method to find the product (3x^2-5)(x^5-9)

asked by Sam on November 8, 2011
68. ## algebra

multiply using FOIL and identify values of a, b, & c. (5x +5)(6x - 8)

asked by Lea on March 7, 2013
69. ## math

Do I use the Foil method to find the product of (9-3i)(9+4i)?

asked by Katie on November 15, 2013
70. ## Math algebra

how do you do this by using the FOIL method? 1. 3x^2 + 22x + 7= 2. 2x^2 + 5x - 12= 3. x^2 - 11x + 28= thank you!

asked by Sara on October 26, 2011
71. ## Algebra

Please Solve: (x+3)(x-5) < 0 I got so far on this and am lost.. (x+3 0) OR (x+3>0 and x-5 and x

asked by Bonnie on July 14, 2009
72. ## Math

Multiply the following using the FoIL method. (5x-2/5) (5x+1/5) I got 25x^2-3x+2/25

asked by Keonn'a on October 27, 2018
73. ## math

use the foil method to find the product.(9x^7-3)(x^9-2).

asked by Brandy on August 29, 2010
74. ## Inter. Algebra

how do you foil 12x squared y cubed?

asked by Andrea on December 2, 2006
75. ## Algebra

Simplify the product using FOIL (6x – 5)(2x – 3) (1 point)

asked by Sandra on March 6, 2014
76. ## Science

Chef Walt is an excellent cook. He works in a very busy restaurant. He cooks for 100's of people each night. Why would Chef Walt use a copper pot instead of an aluminum pot? A) The aluminum pot probably holds less food than the copper pot. B) The copper

asked by Softballperson on May 7, 2018
77. ## chemistry

The density of aluminum is 2.70g/cm3 and the density of chromium is 7.19g/cm3. If eual masses of aluminum and chromium are transferred to equal volumes of water in separate cylinders, which cylinder would have the greates volume change.

asked by Anonymous on September 7, 2009
78. ## chem

in the design of parts, it is genarally a good idea to avoid region or points ofstress concentration since these regions are susceptible to corroisn. give examples of the things that can be done to avoid stress raisers. salt(NaCl) is stored in an

asked by Damon on August 9, 2007
79. ## Physics

A satellite made of aluminum with mass 3500 kg travels on circulated path in 100 km height over the earth. Because of airresistance of the airveil the satellite loses energy and falls in a spiral down to earth. a) What is the mechanical energy of the

asked by Amber on November 17, 2011
80. ## Spanish

Which statement is accurate? a. Fútbol is more important that béisbol in all Spanish-speaking countries. b. Béisbol is more important than fútbol in México. c. Béisbol is more important than fútbol in Cuba, Puerto Rico, and la República

asked by Kaai97 on January 14, 2016
81. ## Spanish

Which statement is accurate? A. Fútbol is more important that béisbol in all Spanish­speaking countries. B. Béisbol is more important than fútbol in México. C.

asked by memeluv on December 6, 2016
82. ## math

Gina cut a piece of ribbon into 3 equal pieces. Then she cut 2 inches off one piece to make a piece 3 inches long. How long was Gina's original piece of ribbon?

asked by bianca on February 6, 2013
83. ## Science - Chemistry

Aluminum oxide is formed from the reaction of metallic aluminum with oxygen gas. How many moles of Aluminum are needed to form 3.4 moles of Aluminum oxide? Writr the equation and balance it. 4Al + 3O2 ==> 2Al2O3 The equation tells you that 4 mols Al are

asked by Sara on January 23, 2007
84. ## Chemistry

Aluminum granules are a component of some drain cleaners because they react with sodium hydroxide to release both heat and gas bubbles, which help clear the drain clog. The reaction is 2 NaOH(aq) + 2 Al(s) + 6 H2O(ℓ) −→ 2 NaAl(OH)4(aq) + 3 H2(g) What

asked by Anonymous on May 1, 2015
85. ## Chemistry

Aluminum sulfate reacts with calcium hydroxide (from lime) to form aluminum hydroxide and calcium sulfate. Write the balanced formula unit equation for the reaction.

asked by Ana on September 28, 2014
86. ## Math

A carpenter had a 20-foot piece of lumber from which he cut three pieces.one piece was 6 1/2 feet long and the other was 3 5/8 feet long. How long was the remaining piece?

asked by Maricel on November 23, 2015
87. ## Chemistry

Aluminum has a density of 2.99 grams per cubic cm. and a specific heat of 0.22 calories per gram degree Celsius. A cube of aluminum is sitting out in the sun where it absorbs 16.2 calories of heat and warms from 62*F to 149*F How many inches wide are the

asked by Liz on February 2, 2011
88. ## Chemistry

Aluminum has a density of 2.99 grams per cubic cm. and a specific heat of 0.22 calories per gram degree Celsius. A cube of aluminum is sitting out in the sun where it absorbs 16.2 calories of heat and warms from 62*F to 149*F How many inches wide are the

asked by Liz on February 2, 2011
89. ## Chemistry

In a certain reaction, 300.23 grams of solid aluminum sulfide combine with unlimited aqueous silver nitrate. How many moles of aluminum sulfide react? How many moles of each product will be produced? First of all, is the reaction a double replacement or

asked by Paula on December 7, 2009
90. ## AP Chem

An electrochemical cell consists of a nickel metal electrode immersed in a solution with [Ni2+] = 1.0 M separated by a porous disk from an aluminum metal electrode. (a) What is the potential of this cell at 25°C if the aluminum electrode is placed in a

asked by Halie on April 1, 2011
91. ## Chemistry

What method of separation would you use for the following mixtures: acetone and water aluminum powder and ethyl alcohol. these were questions asked after a chapter of reading in my chem book. the separation techniques listed in the reading are filtration,

asked by FLASH on September 4, 2006
92. ## Chemistry

(I need help with these two questions. I don’t know how to solve it.) 1. A student takes 215mL of a 5.0M HCI solution and places it into a beaker. The students then adds enough water to the beaker to make 750mL. Calculator molarity of this new solution.

asked by Samantha on April 10, 2018

You have two beakers of acid solution. One beaker contains a 17% acid solution, and the other beaker contains a 91% ACID SOLUTION. How many liters of the 17% acid solution must you mix with the 91% acid solution to make 2 liters of a 56% acid solution?

asked by cierra on November 6, 2015
94. ## physics

A 1.67-kg block of aluminum at 21.7°C is to be melted and reshaped. How much heat must flow into the block in order to melt it? use the following values: For copper: c_copper=0.386 kJ/kg.K T_fusion=1359 K L_fusion=205 kg/K For aluminum: c_aluminum=0.900

asked by maria on December 9, 2011
95. ## math

A rope is 15 feet long. Cut it into 3 pieces. The first piece was 3.57 feet longer than the second piece. The third piece was 2.97 feet longer than the second piece. How long was the third piece of rope?

asked by Carol R on March 24, 2015
96. ## MATH

A PIECE OF METAL3/7/8 INCHES LONG IS TO BE CUT FROM A LONG PIECE OF 5/1/16 INCHES. WHAT WILL BE THE LENGTH OF THE REMAINING PIECE?

asked by ICE on March 11, 2011
97. ## college

If I combined 25.0 grams of aluminum hydroxide with 75.0 mL of 0.500 M HNO3 how many grams of aluminum hydroxide would be formed?

asked by Justin on November 28, 2010
98. ## Chemistry

How many moles of carbonate ions, aluminum ions, and oxygen atoms are present in 39.0 g aluminum carbonate?

asked by Kaitlyn on February 8, 2016
99. ## Literature

I have to make a list on the important actions Pheobe Winterbottom takes in Walk Two Moons. The book says, "It can be anything from 'puts a spell on the prince' or 'eats breakfast' as long as it's important to the character" What are 5 actions I can write

asked by mysterychicken on October 15, 2009
100. ## Math

Allen has a piece of rope that is 84 inches long. He cuts off one piece that is 43 3/4 inches long and another piece that is 31 5/8 inches long. What is the total length of the remaining piece of rope after the two cuts are made?

asked by Aria on October 13, 2015