Friday

December 9, 2016
Total # Posts: 8,165

**Chemistry**

60g/1.42g/ml= 42.25ml Molarity concentrated sol= .060/63*1/42.25= 2.25 so you want to dilute it 2.25/1 times, which means one part concentrated HNO#, 1.25 part water. One part is 2ml, so 1.25 part water is 2.50ml First, the pure acid is what molarity? 1.42 x 1000 x 0.70 x (1/...

*August 7, 2014*

**math**

A jar contains 20 marbles: 4 red, 6 white and 10 blue. If you remove 1 marble at a time, randomly, what is the minimum number that you must remove to be certain that you have at least 2 marble of each color? I guessed the answer was 18 and it was correct but I don't know ...

*August 6, 2014*

**math**

In the z transformation formula, z = (x – M)/s the x stands for __________. (Points : 1)

*August 3, 2014*

**math**

Of the books in a library, 1/3 came from Robbie's collection and 15 came from Marta's. Of the rest, 15 were Elena's 1/5 were Winfield's, and 5 were purchased from the bookstore. How many book are there in the library?

*July 30, 2014*

**math**

How many quarts of water must be added to 18 quarts of a 32% alcohol solution to dilute it to a solution that is only 12% alcohol.

*July 30, 2014*

**math**

Avery paid $168 on a cell phone. What was the original price of the phone if he got it at a 30 percent discount?

*July 30, 2014*

**math**

Mrs. Richmond bought some apples and pears in the ratio 3:5. After she gave away 3/5 of the apples and 40 pears, the ratio of apples to pears became 2:5. An apple costs 30 cents. A pear costs 15 cents more than an apple. How much did Mrs. Richmond pay for the fruit?

*July 28, 2014*

**math**

The square of a certain whole number N is N squared. If 60 is a factor of N squared, its possible that __ is not a factor of N squared.

*July 28, 2014*

**PHI 208 final exam**

hope

*July 27, 2014*

**math**

ya don't say. I got the answer 2D+40c. but the answer key said it was 2D+.4c

*July 27, 2014*

**math**

The charge for renting a rowboat on Loon Lake is D dollars per hour plus c cents for each minute into the next hour. How many dollars will Mr.Wilson pay if he used a boat from 3:40 P.M. to 6:20 P.M.

*July 27, 2014*

**chemistry**

1-Dinitrogen tetroxide (N2O4) dissociates according to the equation: N2O4 ⇌ 2NO2 An equilibrium reaction mixture at 25 ºC was found to have the partial pressure of N2O4 as 72 kPa whilst the partial pressure of nitrogen dioxide (NO2) was 29 kPa. Calculate Kp for the ...

*July 27, 2014*

**math**

A box contains 4 red cards, 6 blue cards, and 10 green cards. What is the smallest number of cards we must remove from the box to make sure that we have 2 cards of the same color?

*July 27, 2014*

**math**

The difference between one half of a number and one fifth of it is 561. Find the number.

*July 24, 2014*

**math**

2 triangles of the same shape are always A) similar B) equilateral C) congruent D) symmetrical E) equal

*July 24, 2014*

**math**

1/a is a fraction. 1 is the numerator and a is the denominator. you need to plug in for a but I don't know how to solve it

*July 24, 2014*

**math**

a= 1/a, then a squared=?

*July 24, 2014*

**math**

The lengths of the diameters of two concentric circles are 6 and 8. What is the distance between the circles?

*July 24, 2014*

**math**

The cost of mailing a package is c cents for the first b ounces and d cents for each additional ounce. find the cost, in cents, for mailing a package weighing f ounces if f is more than b

*July 24, 2014*

**Algebra**

2.5

*July 23, 2014*

**math**

If 25 times were moved from Box A to Box B, there would be an equal number of dimes in both boxes. If 100 dimes were moved from Box B to Box A, the ratio of dimes in Box A to Box B would be 7:2. What was the original number of dimes in Box A?

*July 21, 2014*

**Trigonometry**

oN A LEVEL GROUND, A 5FT. PERSON AND A FLAGPOLE CAST SHADOWS OF 10 FEET AND 60 FEET RESPECTIVELY. WHAT IS THE HEIGHT OF THE FLAGPOLE?

*July 21, 2014*

**Trigonometry**

On a level ground, a 5 ft. person and a flagpole cast shadows of 10 feet and 60 feet respectively. What is the height og the flagpole?

*July 21, 2014*

**chemistry**

4. Calculate the Gibbs’ free energy change for the reaction Mg(s) + H2O(g) → MgO(s) + H2(g) carried out at 100ºC given the data below. Under these conditions is this reaction product favoured? ΔHºformation (kJ mol^-1) MgO(g) -602 H2O(g) -242 H2(g) 0 ...

*July 19, 2014*

**chemistry**

3. Calculate the standard entropy change for the reaction: N2 + 3H2 → 2NH3 given the standard entropies Sº(N2)(g) = 191.6 J K^-1 mol^-1 Sº(H2)(g) = 130.6 J K^-1 mol^-1 Sº(NH3)(g) = 193.3 J K^-1 mol^-1

*July 19, 2014*

**chemistry**

2. Calculate the enthalpy change of combustion for ethene gas (C2H4) given the following enthalpy changes of formation: ΔHºf(C2H4)(g) = +52 kJ mol^-1 ΔHºf(CO2)(g) = -394 kJ mol^-1 ΔHºf(H2O)(g) = -286 kJ mol^-1

*July 19, 2014*

**chemistry**

1. Calculate the standard enthalpy change for the reaction: C2H4(g) + H2(g) → C2H6(g) given that the enthalpy of combustion for the reactants and products are: ΔHºc(C2H4)(g) = -1411 kJ mol^-1 ΔHºc(C2H6)(g) = -1560 kJ mol^-1 ΔHºc(H2)(g) = -...

*July 19, 2014*

**math**

Carrie can inspect a case of watches in 5 hours. James can inspect the same case of watches in 3 hours. After working alone for 1 hour, Carries stops for lunch. After taking a 40 minute lunch break, Carrie and James work together to inspect the remaining watches. How long do ...

*July 17, 2014*

**math**

mr. lee had a bag of red beans and a bag of black beans. 20% of the total number of beans were black, and there were 180 ounces more red beans than black beans. he transferred some red beans to the bag containing black beans, so that, the bag now contained 30% of the total ...

*July 17, 2014*

**math**

A Number N Divides Each Of 17 And 30 With The Same Remainder In Each Case. What Is The Largest Value N Can Have?

*July 17, 2014*

**math**

All sides are congruent.

*July 16, 2014*

**nau**

4x+y=21 7x-4y=8 21*8=168 ------------- 8(4x+y)=21(7x-4y) Solve

*July 16, 2014*

**math**

A girl walks 3/4 of the way home in 18 minutes. At the same rate, she can walk the rest of the way home in A. 4 1/2 minutes B. 6 minutes C. 9 minutes D. 24 minutes

*July 16, 2014*

**math**

A girl walks 3/4 of the way home in 18 minutes. At the same rate, she can walk the rest of the way home?

*July 16, 2014*

**math**

In a certain class there are 12 boys and 18 girls. If the class average for an algebra exam is 90 and the boys' average score is 87, what is the girls' average score?

*July 16, 2014*

**accounting**

A partner withdrew Rs.2000 at the beginning of every month.the rate of interest on drawings is 10%per annum. What is the amt. of interest?

*July 14, 2014*

**Soil Chemistry**

how is carbon dioxide different than water in terms of the behavior of each compound in Earth's atmosphere?

*July 11, 2014*

**Clincal**

A 12-year-old boy presents with his farther to the ER due to open wounds to his arm, hand, and upper leg. The injury occurred when the boy fell on a barbed-wire fence at the farm while running in the field. Diagnosis: Multiple lacerations to the right forearm, right hand, and ...

*July 11, 2014*

**Commerce**

Would it be called statistic, if it is said that there are 2000 students in the school

*July 10, 2014*

**Physics**

An automobile moving at a constant velocity of 25m/s passes a gasoline station. Two seconds later, another automobile leaves the gasoline station and accelerates at a constant rate of 4.0m/s^2. how soon will the second automobile overtake the first?

*July 10, 2014*

**physics**

what is the resultant of two 65N identical one acting easterly and the northerly

*July 8, 2014*

**english**

What is Bronte's main purpose in describing Jane's meals and activities at Lowood? A)to show how all schools operate B) to show the discomforts she endures at Lowood C) to show the interesting aspects of Jane's life at Lowood D) to show how students interact with ...

*July 7, 2014*

**chemistry**

How many mol of Argon is required to exert a pressure of 1.00 MPa at 50 ºC in a vessel that has a volume of 14 litres? (R = 8.314 J K^-1 mol^-1)

*July 6, 2014*

**chemistry**

What is the volume of 14 mol of ideal gas if its pressure is 233 kPa and its temperature is 140 ºC? (1 mol of ideal gas at STP occupies 22.4 L).

*July 6, 2014*

**chemistry**

2.00 m^3 of nitrogen gas at 14 ºC and 100 kPa is compressed to occupy 0.50 m^3. and its temperature rises to 42 ºC. Calculate the new pressure of the gas

*July 6, 2014*

**chemistry**

calculate the mass of water contained in 4.021 m^3 of saturated air at 27 ºCgiven that the saturate d vapour pressure of water at 27 ºC is 3.53 kPa. (RMM of water is 18.02, R = 8.314 J K-1 mol^-1

*July 6, 2014*

**Soil Chemistry**

Understanding the strengths of carbon halogen bonds can help us to understand the behavior of CFCs and related molecules. Arrange the members of the set of carbon halogen bonds shown below in the order of bond strength. A) carbon dioxide B) methane C) ozone D) water A) c > ...

*July 6, 2014*

**math**

there are seven consecutive even numbers .if the largest no is x write an algebraic expression for the middle no . if the middle no is 48 find the value of smallest no

*July 6, 2014*

**Soil Chemistry**

Understanding the strengths of carbon halogen bonds can help us to understand the behavior of CFCs and related molecules. Arrange the members of the set of carbon halogen bonds shown below in the order of bond strength. A) carbon dioxide B) methane C) ozone D)water A) c > b...

*July 5, 2014*

**Soil Chemistry**

Gasoline producers add oxygenated chemical compounds to reduce the amount of carbon monoxide produced when the fuel is burned. Methyl t-butyl ether (MTBE) is one such oxygenate that is no longer used because of health and environmental concerns. what are the correct exponents ...

*July 5, 2014*

**Soil Chemistry**

thank you so much damnon....and thanks for the article...I have a way better understanding of it now...:)

*July 5, 2014*

**Soil Chemistry**

Global temperatures are increasing and this increase is probably due to increasing concentrations of greenhouse gases present in A) the troposphere which absorbs outgoing IR radiation B) the stratosphere which absorbs outgoing IR radiation C) the troposphere which absorbs ...

*July 5, 2014*

**AP Macroeconomics **

Assume that the mix of goods in a basket is kept constant for long periods. If the price of one good rises very rapidly over several years, what will happen to the relative importance of the other goods in the basket? Is this a problem? If the price of coffee increases, we get...

*July 3, 2014*

**english**

What is Bronte's main purpose in describing Jane's meals and activities at Lowood?

*July 2, 2014*

**Soil Chemistry**

I am only given P1V1T1 though...I am not given the other values..P2V2 and T2

*July 1, 2014*

**Soil Chemistry**

Using the gas laws, calculate the new volume of methane gas at STP, which has escaped from a landfill and been captured at an initial pressure of 1.50atm, an initial volume of 30.0L and an initial temperature of 40.0C.

*July 1, 2014*

**Soil Chemistry**

an initial pressure of 1.50atm, an initial volume of 30.0L and an initial temperature of 40.0C.

*July 1, 2014*

**Soil Chemistry**

Chlorine is widely used to treat municipal water supplies and swimming pools. If the volume of a sample of Cl2 gas is 8.73L at 755mmHg and 24.0C, how many grams of Cl2 gas are in this sample? This is one of those multi step problems that I get lost....I need to to know how to ...

*June 30, 2014*

**Soil Chemistry**

In saturated soils, oxygen is quickly depleted and microbes must utilize the next most favorable electron acceptor, in this case sulfate (SO42-). Under these conditions, Mn (and Fe) are oxidized to Mn2+ (and Fe2+). Select the correct oxidation and reduction pair for Mn. A. ...

*June 30, 2014*

**economic**

Management and ownership of business are separate A) Sole Proprietorship B) Corporation C) Partnership I said a

*June 30, 2014*

**math**

100-41= 59

*June 30, 2014*

**Math**

Integrate and simplify the following function: y= ∫(ln√x/x^2)+x 2^(3-5x^2))dx

*June 29, 2014*

**Math**

Show that the derivative of y= cosh-1 (2x-1) is: dy/dx = √1/(x2-x)

*June 29, 2014*

**physics**

A missile is fired from a launcher with an initial velocity of 250 m/s at a target located 500 m above the launcher and at a horizontal distance of 3000 m. Determine the following: i) The possible firing angles required to hit the target. ii) The maximum height reached for all...

*June 29, 2014*

**chemistry**

Draw “arrows in a box” diagrams to illustrate the ground-state electronic configuration of the following species: 12 6C , 32 2 16 S − 28 14 Si , 57 2 28 Ni + , 35.5 17Cl− , 40 2 20Ca + , 31 15P

*June 22, 2014*

**chemistry**

Sulphuric acid (H2SO4) solution reacts with magnesium metal (Mg) to magnesium sulphate and hydrogen according to: H2SO4 + Mg → MgSO4 + H2 How many litres of 5.00 M sulphuric acid would be required to dissolve 20.00 g of magnesium and how many mol of hydrogen would be ...

*June 22, 2014*

**ALGERBRA**

A STATE LOTTERY IS DESIGNED SO THAT A PLAYER CHOOSES FIVE NUMBERS FROM 1 TO 30 ON ONE LOTTERY TICKET. WHAT IS THE PROBABILITY THAT A PLAYER WITH ONE TICKET WILL WIN? WHAT IS THE PROBABILITY OF WINNING IF 100 DIFFERENT TICKETS ARE PURCHASED?

*June 18, 2014*

**Statistics**

The complement of P(B | A) is 1 - P(B | A). Is it also true that 1 - P(B | A) = P(B' | A), where B' means the complement of B?

*June 13, 2014*

**Math**

In a sample of 78 widgets, 2 were defective. How many defective widgets would you expect in a sample of 468 widgets?

*June 12, 2014*

**science 1 question!!!**

Thanks so much Danny! 4/4 100%

*June 5, 2014*

**Physics (electricity and Magnetism)**

A long straight and thin wire has a charge Q per unit length. It is also carrying a current I. A point charge is moving with a velocity v parallel to the conductor, at a distance d from it. Find the velocity v, supposing a correct direction for the current and the current ...

*June 1, 2014*

**math**

gail borrowed $3600 from a bank to buy a washing machine she pays back the loan in 24 monthly instalments at a simple interest rate of 2% a)calculate the simple interest on the loan b)the total amount to be repaid c)if gail repays the loan in 24 equal instalments ,find the sum...

*May 31, 2014*

**Physics **

A projectile is launched at an angle of 34.0o above the horizontal. The projectile has a mass of 1.50 kg and is given an initial speed of 20.0 m/s. a) What is the initial kinetic energy of the projectile? b) By how much does the gravitational potential energy of the projectile...

*May 30, 2014*

**MATH PLZ HELP**

the guys right 25 is the answer i got 100%

*May 29, 2014*

**Geometry**

If m<AHM = 3x+5 and m<TMH = 7x-27, find m<AHM prntscr(dot)com/3n61w3 For figure required for problem.

*May 27, 2014*

**chemistry**

How much naoh and hno3 is needed to make nano3?

*May 26, 2014*

**maths**

If x and y are positive integers, and square root = y + 3, then y^2 = ?

*May 26, 2014*

**physics**

Gamma rays (ã-rays) are high-energy photons. In a certain nuclear reaction, a ã-ray of energy 0.510 MeV (million electronvolts) is produced. Compute the frequency of such a photon.

*May 24, 2014*

**appliance repair**

Which one of the following letters is used in formulas as the symbol for voltage? A. P B. W C. I D. E

*May 22, 2014*

**Help me? Thanks~**

22. The joints highlighted in the image below are ______________ joints. image of transparent body with the spine highlighted the answer is vertbrate

*May 22, 2014*

**Algebra**

Did you ever get it?

*May 21, 2014*

**help please on this **

Making a vaccine for HIV is difficult because the virus has a rapid rate of (A)__________. This is because it is a(n) (B)________ - its genetic material is RNA instead of DNA.

*May 21, 2014*

**English**

The question was "What lesson or meaning do you think this story held for the British audience of the Victorian Era?" This is for the story The Mark of the Beast by Rudyard Kipling. I was thinking that the answer was that the lesson was that just because someone ...

*May 21, 2014*

**Calculus **

An inverted conical tank is 3m tall and 1m in diameter at its widest point. The water is being pumped out of a spout 2m above the top of the tank. Recall that the density of water is ρ = 1000kg/m^3 (a) Find the work needed to empty the tank if it is full. Include units. (...

*May 20, 2014*

**biology**

budding

*May 19, 2014*

**Chemistry**

could you set this up for the first one for me please then i can do the other two

*May 18, 2014*

**Chemistry **

Calculate ΔG∘ at 298 K for the following reactions. Ca(s)+CO2(g)+12O2(g)→CaCO3(s) 2KClO3(s)→2KCl(s)+3O2(g) CO(g)+H2O(g)→H2(g)+CO2(g)

*May 18, 2014*

**Need help with pre cal hw**

1. A party of hikers walks 8 km from camp on 30 degrees, then turns and walks 6 km on course 160 degrees. Find the magnitude of the net displacement from camp. 2. A ship leaves port A and sails 61.1 km course 131 degrees 50' to point B. Then it sails 76.5 km on course 36 ...

*May 18, 2014*

**Algebra**

Update ?

*May 16, 2014*

**Math 2**

1/5 / 10 = 1/5 * 1/10 = 1/50 So d

*May 14, 2014*

**Algebra**

So we get -10 < -2 +8x and -2+8x<22 now we have -8<8x and 8x<24 so we have -1<x and x<3 thus -1<x<3

*May 14, 2014*

**Algebra**

break into two equations

*May 14, 2014*

**Chemistry **

Tarnish on iron is the compound FeO. A tarnished iron plate is placed in an aluminum pan of boiling water. When enough salt is added so that the solution conducts electricity, the tarnish disappears. Imagine that the two halves of this redox reaction were separated and ...

*May 14, 2014*

**ALGEBRA**

there is an error in the equatiion i believe?

*May 14, 2014*

**Chemistry **

Ni2+(aq)+Mg(s)→Ni(s)+Mg2+(aq) Indicate the half-reaction occurring at Anode. Indicate the half-reaction occurring at Cathode.

*May 14, 2014*

**History**

Are you talking bout Canadian History?

*May 13, 2014*

**Geometry **

Let O and H be the circumcenter and orthocenter of triangle ABC, respectively. Let a, b, and c denote the side lengths, and let R denote the circumradius. Find OH^2 if R = 7 and a^2 + b^2 + c^2 = 29. I tried to draw a diagram but it didn't work out too well. Could I have ...

*May 13, 2014*

**Math Solve for X?**

You should multiply both sides by x^2+5x-24 so we get 5x^2-12x <= 0 now we get 5x^2 <= 12x Divide both sides by x and we get 5x <=12 so x <= 12/5

*May 13, 2014*

**math**

Plug in some numbers.

*May 13, 2014*

**geometry**

correct so it is equal to 500 * (1+0.04)^5 Now solve

*May 13, 2014*