Total # Posts: 464
Use the calculation of specific heat for your metal as an example and determine the effect on specific heat if the sample temperature is changed. Does this small loss in heat significantly (>5%) affect your value for the specific heat of the metal? How would I solve this? ...
November 15, 2016
The toxic metal cadmium Cd2+ has a tendency to complex with as many as 4 Cl- ions. The complexation reactions can be written as: Cd2+ + Cl- ---> CdCl+ ``````` log Kf,1 = 1.98 Cd2+ + 2Cl- ---> CdCl20 `````` log Kf,2 =2.60 Cd2+ + 3Cl- ---> CdCl3- `````` log Kf,3 = 2.40 ...
September 15, 2016
The problem is as follows: The toxic metal cadmium Cd2+ has a tendency to complex with as many as 4 Cl- ions. The complexation reactions can be written as: Cd2+ + Cl- ---> CdCl+ log Kf,1 = 1.98 Cd2+ + 2Cl- ---> CdCl2^0 log Kf,2 =2.60 Cd2+ + 3Cl- ---> CdCl3- log Kf,3...
September 15, 2016
Sally travels by car from one city to another. She drives for 29.0 min at 63.0 km/h, 37.0 min at 32.0 km/h, and 14.0 min at 26.0 km/h, and she spends 14.0 min eating lunch and buying gas.
September 13, 2016
Ness won $2400000 in a state lottery. After paying 39% of her winnings to taxes, she invested some of the money into an account earning 4.8% interest and the rest into an account earning 3.9% interest. If the total interest earned was $65655, how much did she invest into each ...
September 7, 2016
The vector u = (4300, 5200) gives the number of units of two models of laptops produced by a company. The vector v = 1800, 1200 gives the prices (in dollars) of the two models of laptops, respectively. Identify the vector operation used to increase revenue by 5%. (the // ...
July 14, 2016
Here are some examples of molecules: Cl2, CO2, SO2, and CF4. Each of these is related in that they're all bonded covalently. Which of these is a covalently-bonded molecule also? A. He atoms B. K2S C. BaBr2 D. P2O4
June 29, 2016
If our planet is travelling at 10000 mph (just using hypothetical numbers) and you launched a rocket into space at 10000 mph (ignoring the planets rotational speed to keep this simple) on the same exact path the planet is moving, would the rocket be moving at 20000 mph in space?
May 28, 2016
There are five sand which fillings - ham, cheese, tomato, lettuce and totally plain. How many combinations? I make 11. Ham, h & c, h & t, h&l; cheese, c & t, c & l; tomato; lettuce, l & t; sandwich with no filling. Total is 11. Some doubt in the family with this! Many thanks, ...
April 13, 2016
Small amounts of chlorine gas can be gener- ated in the laboratory from the reaction of manganese(IV) oxide with hydrochloric acid: 4 HCl(aq) + MnO2(s) → 2 H2O(l) + MnCl2(s) + Cl2(g). What mass of Cl2 can be produced from 41.8 g of MnO2 with an excess of HCl(aq)?
March 30, 2016
the length of a rectangle is 4cm more than the width of the rectangle. If you increase the length by 8cm and decrease the width by 4cm, the area will remained unchanged. Find the original dimensions
February 22, 2016
Question:So,far Michael has earned the following scores on five 100-point tests this semester: 72, 94, 85, 83, 97. What score must he earn on the sixth 100-point test of the semester if he wants to make an 88 point average for the six tests? Answer Choices A. 88 B. 100 C. 97 D...
February 3, 2016
can someone explain to me what happens when zinc and copper sulfate react? I know its a redox reaction and it gives off heat making it exothermic, but don't know whats actually happening in that reaction. can someone explain to me that reaction?
January 12, 2016
Compute the initial upward acceleration of a rocket of mass 1.5 ✕ 104 kg if the initial upward force produced by its engine (the thrust) is 2.7 ✕ 105 N. Do not neglect the weight of the rocket. Pleas tell me the steps, I've tried getting the acceleration and ...
December 15, 2015
Suppose we had mixed 52.37 mL of 1.00 M HI solution with 25.42 mL of 1.00 M KOH solution, and measured a heat of reaction of -1.52 kJ. What is ΔH for this reaction, in kJ? Assume that all solutions have the same density as water (1.00 g/mL).
December 11, 2015
A factory creates wooden beads used for various arts and crafts projects. One particular type of bead is in the shape of a cube. Each side of the bead is 0.25 inches long. A cylindrical hole with diameter of 0.12 inches is cut through the bead so that string can be threaded ...
November 23, 2015
I know don't know if this right P(X)<115)= 12.1 (115-mean) how do I get the mean or is there a formula that can help me solve this? A population of line voltages has a standard deviation of 1.20 volts. What value would the mean line voltage have to be so that 12.1% of ...
October 5, 2015
A rectangular picture frame has a perimeter of 58 inches. The height of the frame is 18 inches. What is the width of the frame? Please help show work and help answer thanks
September 25, 2015
Two planes leave New Orleans at the same time. Plane A heads north and Plane B heads south. After 4 hours and 15 minutes, the two planes are 4568.75 miles apart. Also, Plane A is traveling 53 mph faster than Plane B. At what speeds are the two planes traveling at? How far did ...
September 2, 2015
in our notes for strengths of acids and bases it says that you could add a strong/weak acid with a strong/weak base and it will give you a low, medium or high delta h. so wouldn't acids and bases be related to thermochemistry?
July 16, 2015
You are considering two mutual funds for your investment. The possible returns for the funds are dependent on the state of the economy and are given in the accompanying table. State of the Economy | Fund A | Fund B Good | 20% | 40% Fair | 10% | 20% Poor | -10% | -40% You ...
May 24, 2015
Determine the hydroxide ion concentration in a solution that is 0.0004 M HCl. Answer in units of M. I have no idea how to start, I just need to know what I need to solve for and hoe to set it up, I know the formula pOH^-=-log[OH^-] I just don't know where to plug things in...
April 16, 2015
During a severe thunderstorm, Tim saw a flash of lightning and then six seconds later heard a clap of thunder. The speed of sound is 1088 ft/sec. How far is Tim from the lightning? Nearest Thousand Feet.
February 27, 2015
Algebra please help
Lisa evaluated the expressions 2x and x squared for x=2 and found that both expressions were equal to 4. Lisa concluded that 2x and x squared are equivalent expressions. How could you show. Lisa that she is incorrect? Please help explain thanks
January 21, 2015
A boat is going 30 mph. It's direction is 100 degrees east of north. The water current is 15 mph and has a direction of 22 degrees east of north. Find the magnitude, and direction of boat.( with water current)
January 20, 2015
The town of Rayburn received 6 more inches of snow than the town of Greenville. Let g represent the amount of snow in Greenville. Write an algebraic expression to represent the amount of snow in Rayburn.
January 14, 2015
Jill, Meg and Beth are sisters. Jill is 2 years younger than Meg. Beth is half as old as Meg. Let m represent Meg'a age. Write 2 other algebraic expressions based on the situation. Tell what each expression represents, and what the variable stands for in each expression. ...
January 14, 2015
A very old vending machine accepts only nickels (n) and dimes (d). Candy costs up to $0.50, but sometimes the machine will dispense candy without any coins being inserted into the machine. Which inequality shows all of the ways to obtain a candy bar from the machine?
January 13, 2015
P.E. help please
45% of 10 is 4.5 So the answer is c Multiply your answer by 10 and the number your trying to get the % from by 10 as well 10x10=100 4.5x10=45 Percent is a calculation of part of 100. And in this case you make the "10" a 100 by multiplying it by 10
December 3, 2014
A puck of mass 0.165 kg, initially resting on ice, is hit by a stick to gain a speed of 32.0 m/s and then slides 25.0 m to lose 5.00% of its kinetic energy. (a) What is the work done on the puck by the stick? (b) What is the kinetic friction coefficient between the ice and puck?
October 11, 2014
If only natural gas is hit, the income will be $140,000. If nothing is hit, there will be no income. If the probability of hitting oil is 1/40 and if the probability of hitting gas is 1/20, what is the expectation for the drilling company?
September 10, 2014
A rifle with a muzzle velocity of 480 m/s shoots a bullet at a target 45.6 m away. How high above the target must the rifle barrel be pointed to ensure that the bullet will hit the target? Neglect air resistance.
September 7, 2014
glycine and lysine, have the following values of the relevant acid dissociation constants (pKa) glycine, pKa=2.35 lysine,pKa=10.79 For an aqueous solution of glycine alone, calculate the value of pH at which the ratio of the concentration of neutral glycine zwitterions to the ...
August 26, 2014
a) Carbon [He]2s²p² b) Silicon [Ne]3s²p² Hund rule -> fill from bottom to top Pauli -> first you fill orbitals with one spin and then the other ex. if you have 4 electrons in p orbitals P 11 1 1 __ __ __ p.s. if they don't delete this too
August 26, 2014
Determine the potential (V) by which a proton must be accelerated so as to assume a particle wavelength of 0.0293 nm. ---- This is what I did, dunno if right - wavelength in meters = 2.93*10^-11 m - used DeBroglie relation to find energy lambda = h / mv, v from kinetic energy...
August 24, 2014
a) Calculate the number of moles of nitrogen dioxide, NO2, that could be prepared from 79.0 mol of nitrogen oxide and 82.0 mol of oxygen. 2NO(g)+O2(g)⟶ 2NO2(g) b) Identify the limiting reagent and the excess reagent in the reaction. What would happen to the potential ...
August 24, 2014
A compound of chlorine and fluorine, ClFn, reacts at about 75oC with uranium metal to produce uranium hexafluoride, UF6 and chlorine monofluoride, ClF (g). A quantity of uranium produced 3.53g UF6 and 343 mL ClF at 75oC and 2.50 atm. What is the formula (n) of the compound?
May 26, 2014
7. Paula is an office manager for ABC Advertising. She has been tasked with finding a copy machine that falls within a budget of $750 per month. She finds a company that will lease the machine for $275 a month. Each copy costs 4¢ and a ream of 500 sheets of paper costs $5...
February 2, 2014