krystal

Most popular questions and responses by krystal
1. chemistry

Magnesium reacts with iron(II) chloride according to the equation Mg(s) + FeCl2(aq) → MgCl2(aq) + Fe(s) a. Is magnesium oxidized or is it reduced? Magnesium is reduced. b. Is iron(II) ion oxidized or is it reduced? Iron(II) ion is oxidized . c. What is

2. chemistry

In this equation is Fe(OH)3 and NaCL a solid liquid gas or aqueous? FeCl3 (aq) + 3NaOH(aq)=Fe(OH)3+NaCl

3. chemistry

a. What is the net charge on valine at pH 1? b. at pH 7? c. at pH 14?

4. chemistry

Mercury reacts with oxygen to produce mercury(II) oxide. Hg(l) + O2(g) → HgO(s) a. Balance the reaction equation. Include physical states. 2Hg(l) + O2(g) → 2HgO(s) b. What is the theoretical yield (in grams) of HgO if 255 g of Hg are reacted with 255 g

5. math

Find the sequence of the first five partial sums S1, S2, S3, S4, and S5 of the geometric sequence by adding terms. 9, 12, 16, 64/3, 256/9,... S1 = S2 = S3 = S4 = S5 =

block 1 of mass 1 slides from rest along a frictionless ramp from height h=2.50m and then collides with stationary block 2, which has mass2=2.00 m1. After the collision, block 2 slides into a region where the coefficient of kinetic friction is 0.500 and

7. organic chemistry

suppose solute A has a partition coefficient of 4.0 between diethyl ether and water. Demonstrate that if 100mL of solution of 5.0g of A in water were extracted with two 25mL portion of diethyl ether, a smaller amount of A would remain in the water than if

8. biochemistry

What is the net charge on Phe-Asp at each pH? a. pH 1 b. pH 7 c. pH 14

9. chemistry

Explain why an opened bottle of carbonated water keeps its fizz longer if kept in a refrigerator than if kept at room temperature. a. As time elapses the concentration of CO2 inside a closed refrigerator increases. The increased partial pressure of CO2

An ant travels 2.78 cm (West) and then turns and travels 6.25cm (south 40 degrees East). What is the ant's total displacement?

11. Algebra 2

For the period 1990-2002, the number s (in thousands)lf cellular telephone subscribers in the United States can be modified by S=858t^2 + 1412t + 4982 where t is the number of years since 1990. In what year did the number of subscribers reach 50 million?

12. chemistry

a. Cl2 + 2NaI → 2NaCl + I2 This is a single replacement reaction. b. 2K + 2HCl → 2KCl + H2 This is a single replacement reaction. c. N2 + 3H2 → 2NH3 This is a synthesis reaction. d. 2KClO3 → 2KCl + 3O2 This is a decompisition reaction

13. Physics

A motorist traveling at 30 m/s passes a parked police car. At the instant the motorist passes the police car, the police car starts chasing the motorist with an acceleration of 3 m/s^2. How far does the police car have to travel to catch the motorist?

14. Physics HELP A,S.A.P!

Q: Tarzan, who weighs 688N, swings from a cliff at the end of a vine that is 18m long. From the top of the cliff to the bottom of the swing, he descends by 3.2m. The vine will break if the force on it exceeds 950N. a)Does the vine break? b) If no, what is

15. Algebra 2

At the ruins of Caesarea, archaeologists discovered a huge hydraulic concrete block with a volume of 945 cubic meters. The block's dimensions are x meters high by 12x - 15 meters long by 12x - 21 meters wide. What is the height of the block? Can someone

16. chemistry

For the reaction between nitrogen and oxygen to form nitric oxide, beginning with 0.067 mol of N2, N2(g) + O2(g)= 2 NO(g) a. how many moles of O2 are required to completely consume the N2? b. how many moles of NO are obtained when the N2 is completely

17. chemistry

A pan full of hot salt water, NaCl(aq), is cooled and NaCl(s) precipitates. Explain why this happens. Chloride ions are more strongly attracted to the metal in the pan than the sodium ions at low temperatures. As the vapor pressure of the solution

18. Chemistry

Both carboxylic acids and phenols react with strong bases to produce _____. gaseous products the conjugate base of the carboxylic acid or phenol a complex with water a stronger acid or phenol

19. biochemistry

a. What is the net charge on valine at pH 1? b. at pH 7? c. at pH 14?

20. chemistry

As the pH of a system decreases: the [H+] decreases the Kw decreases the [OH-] decreases all of the above

21. chemistry

CH4 + 2 O2 = CO2 + H2O Carbon is being oxidized Oxygen is being reduced

22. writing process part 1

I need this paragraph proof read if that's OK. also need to know if it's a fully devolved the topic a high school diploma is important to my future. A high school diploma is important to my future for a number of reasons. The First being to attend college

23. chemistry

Calculate the pH of a 0.0019 M HNO3 solution. 2.7

24. Math

Use the table below to answer the following question. x: 1, 2, 3, 4 y: 1, 4, 9, 16 Which is NOT true about the above table? A: It shows a linear function. B: The variable x increases by 1 each time. C: The rate of change is not constant. D: The variable y

25. chemistry

Give the formula for the conjugate base of each acid. a. HSO4- SO4^2- b. H3PO4 H3PO4 c. HPO42- PO4^2- d. HNO3 NO3^-

Uniform motion Related Problem Five boy scouts biked to Caliraya lake at 5 km/h. their scout master gave them a ride back home in his pickup car, at 20 kph. Find the hiking time if it 6 hors longer than their riding time.

27. Earth Science

If a major hurricane can generate 1.25 x 10 to the 19th power calories of energy per day, and this energy comes from condensation, how many liters of water must condense each day to form hurricane clouds and precipitation?

28. chemistry

Why does a change in pH usually produce a change in the ability of an enzyme to act as a catalyst? A. When the pH changes, the enzyme may lose its native conformation and lose its ability to function as a catalyst. B. When the pH changes, enzymes are

29. algebra

Two ships make the same voyage of 3000 nautical miles. The faster ship travels 10 knots faster than the slower one (a knot is 1 nautical mile per hour). The faster ship makes the voyage in 50 hr less time than the slower one. Find the speeds of the two

30. Earth Science

How tall in miles would a stack of 4.5 billion pennies be?

31. chemistry

Calculate the pH of a 0.0019 M HNO3 solution.

32. chemistry

Assuming additive volumes, what will be the molarity of the solution that results when 35.5 mL of 2.00 M HNO3 is added to 214.5 mL of water? 0.284 M

33. chemistry

Name each of the following ionic compounds or binary molecules. a. SF2---Sulfur difluoride b. MgF2---Magnesium fluoride c. SnCl2----Tin (II) Chloride d. PF5-----Phosphorus Pentafluoride e. NO2-----Nitrogen Dioxide f. SnO2-----Tin (II) Oxide

34. Algebra 2

The arch of the Gateshead Millennium Bridge forms a parabola with equation y=-0.016(x-52.5)^2+45 where x is the horizontal distance(in meters) from the arch's left end and y is the distance (in meters)from the base of the arch. What is the width of the

35. chemistry

Which of the molecules can form a hydrogen bond with a water molecule? 1. CH3OH 2. CH2=CHCH3 3. CH3CH2SH 4. CH3OCH3

36. chemistry

Aluminum and oxygen react to form aluminum oxide. 4 Al + 3 O2 2 Al2O3 a. What is the limiting reactant if 36.4 g Al are reacted with 36.4 g of O2? O2 b. What is the theoretical yield of Al2O3, in grams? 68.8 g c. If 22.2 g of Al2O3 are obtained, what is

37. chemistry

a. What is the molecular weight of aspirin (C9H8O4)? 180.1574 amu b. What is the mass of 0.00785 mol of aspirin? 1.41 g c. How many moles of aspirin are present in 100 mg of aspirin? Enter your answer in scientific notation. 5E-4 mol aspirin d. How many

38. Chemistry

0.1 mol of HCl is added to 1 L of water. What is [H+] and [OH-]?

39. chemistry

What is the formula weight of Li2CO3? 73.891 amu b. What is the mass of 1.30 x 10-4 mol of Li2CO3? 9.61E-3 c. How many moles of CO32- ions are present in 102 g of Li2CO3? Dont get how to compute

40. Chemistry

A gas, Y, diffuses 1.05 times faster than SO2 gas at the same conditions. What is the molecular weight of gas Y?

41. chemistry

Which has the higher boiling point? (a) CH3CH2CH2CH2CH3 or (b) CH3CH2CH2CH2CH2CH2CH2CH3

42. Physics

A 2kg ball is attached to a 1.5m rope and is swung in a vertical circle. At the top of the swing the ball travels at 5 m/s. What is the tension in the rope?

43. Accounting

The owner's equity of Logan's company is equal to one quarter of the total assets. Liabilities equal \$60,000. What is the amount of owner's equity?

44. chemistry

ndicate whether each solution is acidic, basic, or neutral. a. [H3O+] = 6.9 x 10-1 M This solution is acidic. b. [H3O+] = 8.2 x 10-13 M This solution is basic. c. [H3O+] = 3.2 x 10-1 M This solution is acidic.

45. chemistry

In the reaction below: Increasing the concentration of Cl2 will _____ at equilibrium. HAVE NO EFFECT

46. chemistry

For the combustion of ethane, beginning with 2.6 mol of CH3CH3, 2CH3CH3(g) + 7O2(g) → 4CO2(g) + 6H2O(g) a. how many moles of O2 are required to completely consume the CH3CH3? 9.1 moles b. how many moles of CO2 are obtained when the CH3CH3 is completely

Uniform Motion Related Problem A car travelling at 60 kph left town at 9:00 a.m. Another car travelling at 65 kph left the same place half an hour later to overtake the first. At what time did the second car overtake the first?

48. Algebra 2

How would you describe the pattern of this sequence? 2/3, 4/4, 6/5, 8/6, 10/7 The formula is 2n/n+2 where n is 1, 2, 3, 4, 5

49. physics

if Royce was 10 years old and he had a mass of 30kg. but by the time he turned 16 his mass has grown to 60kg. how much larger is the gravitational force between Royce and earth at age 16 compared to age 10

50. math

Find the indicated term of the geometric sequence. a1 = 7, a4 = 189/8 , 8th term

51. chemistry

Benedict's reagent is used for detecting reducing sugars because _________. the —OH groups are exchanged for hydrogens. the copper ion in the reagent is oxidized as the sugar is reduced. the aldehyde group in the sugar is oxidized. a reduction of the

52. chemistry

What happens to the solubility of oxygen gas (O2) in water in each situation? a. The pressure of O2 over the solution is decreased. solubility decreases solubility remains the same solubility increases b. The temperature is decreased. solubility remains

53. chemistry

1-Butene (CH2=CHCH2CH3) burns in the presence of O2 to produce CO2 and H2O. Write the balanced chemical equation for this reaction (omit physical states and use condensed molecular formulas). CH2CHCH2CH3+6O2=4CO2+4H2O

54. italian

is cappuccino masculine or feminine is giorno masculine or feminine

Uniform Motion Related Problem Two cars, 210 km apart, met each other in 2 hours. If one car travelled at 60 kph, at what rate did the second car travel?

Uniform Motion Related Problem Two planes leave an airport at 2 p.m., one flying south at 450 kph, the other flying north at 675 kph. At what time will they be 3 600 apart?

57. math

Value ways 2 3/5 miles each day.Bill runs 10 miles once every 4 days. In 4 days, who covers the greater distance?

58. chemistry

Benedict's reagent is used for detecting reducing sugars because _________. the —OH groups are exchanged for hydrogens. the copper ion in the reagent is oxidized as the sugar is reduced. the aldehyde group in the sugar is oxidized. a reduction of the

59. chemistry

A bottle of 80 proof alcohol is 40% ethanol and 60% water. What is the solvent in this solution? water

Uniform Motion Related Problem Port A is 25 km downriver from port B. At noon a tugboat leaves port B and travels upstream at 15 kph. At 3 p.m. a hyrodrofoil leaves Port A travelling upstream at 50 kph. At what time will the hydrofoil pass the tugboat?

Uniform Motion Related Problem Chester drove his car at 8:00 a.m. at speed of 45 km/hr. At 9:15a.m. Michael followed with his car. What should be Michael's speed so as to be able to overtake Chester at 1:00 p.m.? How far has Chester travelled when Michael

62. physics

A 0.112 kg meterstick is supported at its 38.6 cm mark by a string attached to the ceiling. A 0.655 kg mass hangs vertically from the 4.74 cm mark. A mass is attached somewhere on the meterstick to keep it horizontal and in both rotational and

63. chemistry

What is the net charge on Phe-Asp at each pH? a. pH 1 b. pH 7 c. pH 14

64. chemistry

Give the formula for the conjugate base of each acid. a. HSO4- H2SO4- b. H3PO4 H4PO4 c. HPO42- H2PO42- d. HNO3 H2NO3

65. chemistry

Aluminum metal reacts with oxygen gas (O2) to form aluminum oxide. a. Write a balanced equation for this oxidation-reduction reaction. (In this problem you need not worry about the physical state of the reactants or product.) 2Al+3O2=2Al2O3 b. which

Uniform Motion Related Problem Jessie has a 15 km head start on Melvin. How long will it take Melvin to catch Jessie if the latter travels at 70 kph and the former at 100 kph?

67. Chemistry

I need to balance this equation by redox reactions with half reactions method NH4ClO4 + Al --> Al2O3 + AlCl3 + NO

68. Math

How do you solve for this:how many gallons of a 10% alcohol solution be mixed with 20 gallons of a 10% acid solution to obtain an 8% acid solution.

69. Math

Find graphing solutions to 4x-y=5

70. physics

A 0.112 kg meterstick is supported at its 38.6 cm mark by a string attached to the ceiling. A 0.655 kg mass hangs vertically from the 4.74 cm mark. A mass is attached somewhere on the meterstick to keep it horizontal and in both rotational and

71. Physics, Desperate Need of help!

Gold, has a mass of 19.32g for wach cubic centimeter of volume, is most ductile metal and can be pressed into a thin leaf or drawn out into long fiber. -If a sample of gold, with a mass of 27.63g is pressed into a leaf of 1.000micometers thickness, what is

72. math

Kool Klothes has determined that the revenue function for selling x thousand pairs of shorts is R(x) = -5x^2 + 21x. The cost function C(x) = 2x + 10 is the cost of producing the shorts. a) How many pairs of shorts must the company sell in order to break

Uniform Motion Related Problem Two cars starting from the same point travel in opposite directions. Car A travels at 80 kph and car B at 110 kph. After how many hours will the cars be 760 km apart?

74. Math

Show that the equation 155x -465y 35 has no integer solutions

75. chemistry

What are [H+] and [OH-] for 0.01 M perchloric acid

76. pre cal

At a distance of 100 feet, the angle of elevation from the horizontal ground to the top of a building is 42 degrees. Find the height of the building

77. physics

A 20.7 cm screwdriver is used to pry open a can of paint. If the axis of rotation is 2.25 cm from the end of the screwdriver blade and a force of 29.3 N is exerted at the end of the screwdriver’s handle, what force is applied to the lid? Answer in units

78. Physics

tammy leaves the office drives 50 km due north, then turns onto a second highway and continues in a direction of 32 degrees north of east for 93 km. At what angle is her displacement? (consider east to be 0 degrees and north 90 degrees)

79. chemistry

Choose the type of shape that best matches to CH4. Linear Trigonal planar Bent Tetrahedral Pyramidal

80. chemistry

a. Listening to the weather report, you hear that the barometer is falling. What part of the barometer is falling? The level of mercury is falling. b. What is happening to the air pressure? The air pressure is decreasing.

81. Physics

A projectile is fired from ground level with a speed of 40 m/s at an angle of 30 degrees and hits a building 100m away. What is the time of flight of the projectile? How high above ground does the projectile hit the building? What is the speed of the

82. chemistry

Consider the following reaction. 2KClO3(s) → 2KCl(s) + 3O2(g) a. How many grams of KCl are produced from the complete reaction of 2.16 mol of KClO3? 161g b. How many grams of KCl are produced from the complete reaction of 52.7 g of KClO3? 32.1 g

83. chemistry

Which of the following atom pairs would most likely be connected by a covalent bond? K and F O and Cl Na and O Na and Cl

84. math 11

Calculate the interest due on the following credit card balances. a)An unpaid balance of \$1623.53 at a rate of 19.50% for 21 days. b)An unpaid balance of 2639.99 at a rate of 22.95% for 30 days.

85. chemistry

Consider the following reaction. 4Fe + 3O2=2Fe2O3 a. How many moles of O2 are required to react completely with 29.8 mg of Fe? 4.00 x 10^-4 moles O2 b. How many grams Fe2O3, are produced from the complete reaction of 17.8 g of Fe? 25.4 g Fe2O3

86. chemistry

Predict the number of covalent bonds formed by each nonmetal atom. a. N-----3 bonds b. Cl-----1 bond c. S-----2 bonds

87. chemistry

Write the formula of the ionic compound that forms between a. copper(I) ions and chloride ions---CuCl b. copper(II) ions and hydrogen sulfate ions--Cu(HSO4)2 c. lithium ions and iodide ions--LiI d. cobalt(III) ions and phosphate ions---CoPO4

88. psychology

Now imagine that you are conducting research on the length of time it takes customers to select items in a grocery store. Assume that your hypothesis is that people will spend more time deciding on more expensive items than on cheaper items. • What might

89. Calculus 1

A filter filled with liquid is in the shape of a vertex-down cone with a height of 12 inches and a diameter of 18 inches at its open (upper) end. If the liquid drips out the bottom of the filter at the constant rate of 5 cubic inches per second, how fast

90. Physics

Instructions for building a buried treasure include the following: Go 872 paces at 167 degrees turn to 286 degrees and walk 135 paces, the travel 319 paces at 152 degrees. A) Find the magnitude of the resultant displacement from the starting point. B) What

91. math 11

Calculate the amount of interest earned in 10 years on \$1000 invested at 3.00% per annum, compunded annually?

92. chemistry

Indicate the number of covalent bonds that each nonmetal atom is expected to form. a. Se is expected to form 2 covalent bonds. b. H is expected to form 1 covalent bonds. c. Br is expected to form 1 covalent bonds. d. N is expected to form 3 covalent bonds.

93. chemistry

What is reduced and what is oxidized in the reaction? 2Mg+O2=2MgO Oxygen is oxidized Mg is reduced

94. chemistry

How many milliliters of 0.729 M NaOH are needed to prepare 150.0 mL of 0.122 M NaOH? 25.1 mL

95. chemistry

What mass of potassium chloride, a salt substitute often used by heart patients, can be produced directly from 5.2 g potassium and 7.9 g chlorine? 9.9 g

96. chemistry

Which of the following atom pairs would most likely be connected by an ionic bond? K and Br S and Br O and Br F and Br

97. Physics

One afternoon, a couple walks five-sixths of the way around a circular lake, the radius of which is 1.45 km. They start at the west side of the lake and head due south to begin with. (a) What is the distance they travel? (b) What are the magnitude and

98. science

I got this homework assignment from my seventh grade teacher I don't understand how to do it. It is Classifying the States using a taxonomic key.

99. Evil PHysics!!!!!!

Hello, I am having trouble with this problem: During volcanic eruptions, chunks of solid rock can be blasted out of the volcano; these projectiles are called volcanic bombs. a)At what initial speed would a bomb have to be ejected, at angle (sigma0=35