Posts by maddy
Total # Posts: 173
Bart and Bethany play a game. They each roll a regular 6-sided die labeled 1to 6. Use an outcome table to show all possible outcomes: (2 marks) is the total number of outcomes 12?
November 23, 2016
Assume that the reaction was limited by the surface area of the nails, making Fe the limiting reactant. Based on the decrease in the mass of nails, calculate theoretical yield of copper. 2Fe+3CuCl2--->2FeCl2+3Cu
October 13, 2016
find the intervals on which f is increasing and decreasing f(x)=(x-2)/(X^2-x+1)^2 I found the derivative a got a whole mess of things: ((x^2-x+1)^2-2(x^2-x+1)(2x-1)(x-2))/(x^2-x+1)^4 Do I have to use the quadratic formula to solve for the vertices to find where it is ...
October 2, 2016
Prepare 30mL of a stock KI soln by mixing 10.0mL of the 0.03M KI in 0.2M KNO3 with 20.0mL of the .2M KNO3 Determine the concentration of the iodide ion. What does it mean by the 0.03M KI in 0.2M KNO3? Is this just bad wording of the question? Am I just mixing the 10.0mL of ....
October 2, 2016
A student prepares a soln that is initally 0.006M Pb2+ and 0.00450M I-. This soln is placed into a 1.00cm wide cuvet and inserted into the spectrometer producing as abosrbance reading of 0.430 at a wavelength of 456nm. What is the equilibrium concentration of the iodide ions ...
October 2, 2016
If the concentration of KCN at the equivalence point is 0.1M and the Ka for HCN is 6.2*10^-10 find the pH at the equivalence point. The reaction is between KOH and HCN From my understanding I have to do a stoichiometric calculation and then use the Henderson-Hasselback ...
September 28, 2016
Can somebody help me understand batteries? I'll explain what I know, then, you can tell me if I'm right or wrong. I know that a battery consists of three main parts: the anode, the cathode, and an electrolyte. The anode is electropositive and the cathode is ...
May 10, 2016
How many grams of NaNO2 must be added to 1 liter of 1.00 M HNO2 solution in order to prepare a buffer solution with pH = 4.14? pH = 3.14? My work: ka = pH(buffer ratio) 4.5 * 10^-4 = 1.000*10^-4.14 (x M of base/1.00 M of acid) x = 6.21 6.21 M = (6.21 moles/1 L)(1 L) = 6.21 ...
February 21, 2016
A 35 micro coulomb point charge is placed 32 cm from an identical 35 micro coulomb charge. How much work would be required to move a 0.5 micro coullomb test charge from a point midway between them to a point 12 cm closer to either of the charges?
February 11, 2016
A large statue in a crate is being moved. The mass of the statue and the crate is 150 kg. As the statue slides down a ramp inclined at 40.0°, the curator pushes up, parallel to the ramps surface, so that the crate does not accelerate. If the statue slides 3 m down ...
December 5, 2015
Graph y=2csc(x-π) New period that I solve for 0<x-π<2π π<x<3π What is my quarter period? I got that it was 3π/4 but when I add this to pi 4 times o reach 4π instead of 3π. Please help.
October 11, 2015
Rationalize the denominator. The twos are outside of the square root signs. 5/(sqrt14)-2 x (sqrt14)+2/(sqrt14)+2 The answer is sqrt14+2/2 I am having trouible understanding hoe to get rid of the 5
August 15, 2015
Read the passage and answer the question that follows: John Brown, supported by abolitionists and Republicans, tried to start a slave revolt. Therefore be it resolved that the defense of slavery is a common cause to all Southern states. At the call of any Southern state, we ...
May 6, 2015
The volume of the nitrogen gas is 125ml atmospheric pressure is 763mm Hg Water temperature is 24 degrees Celcius. The water level inside the eudiometer is the same as the level of water in the beaker. Calculate the pressure of the dry nitrogen gas. PH2=Ptotal-PH2O PH2=763 mm ...
April 9, 2015
If a .750g sample of magnesium chloride is dissolved in water and then treated with a silver nitrate solution how many grams of silver chloride should be collected? I don't understand what my first step should be. The balanced equation is MgCl2+2AgNO3=2AgCl+Mg (NO3)2 Do I ...
April 9, 2015
Fin the value of Theta if sec theta=3 I inverted the value of sec theta to get cos theta=1/3 I then said Theta=cos-1 (1/3) Is thus correct? What is the answer rounded to the tenths place?
February 18, 2015
Find cotangent theta given that cosecant theta equals -3.5891420 and theta is in the third quadrant. I was using the trig identity 1+cot^2theta=csc^2theta I wanted to isolate cotangent so I plugged in 1/sin (-3.5891420) and then squared my answer. I then subtracted one from ...
February 9, 2015
32.0=5.5x10^2(1/T)+14.2 Solve for T I am confused about what the first step would be to solving for T. Would I divide 5.5x10^2(1/T) and move it to the left side? Please help.
January 28, 2015
i need help with more questions in the packet heres my question the poisonous gas hydrogen sulfide, H2S, can be neutralized with a base such as sodium hydroxide, NaOH. THE unbalanced equation for this reaction follows: NaOH(aq)+H2S(g)→Na2S(aq)+H2O(l) a student who was ...
January 12, 2015
i need help with a packet that im struggling with my questions are write the total number of atoms present for the following questions: a. 4SO2 now i tried and got 8O'S and 1S b. 8O2 i tried and got 16 all together c. 3Al2(SO4)3 i tried and got 6Al, 3S, and 12O my next ...
January 12, 2015
i have a homework packet that i am struggling with can you please help me my first question is i have to finish the following equation to balance it out my question is 3Fe3O4+blankAl→blankAl2O3+blankFe now i tried and i got 3Fe3O4+2A=2Al2O3+2Fe i don't know if that...
January 12, 2015
I need some help with determining the equation for this problem. "The block of mass m is released from rest on the frictionless incline. After sliding a certain distance, it compresses a spring and comes to rest at a distance of y beneath its original position. How much ...
December 14, 2014
Jason Printing has $85,000 to invest. They can invest in Wilder Revenue at 10% compounded semiannually or at Cheapskate Investments at 9.8% compounded monthly. a) Calculate the two APYs and compare them to determine your answer. Make sure to distinguish which APY belongs to ...
April 15, 2014
Jason Printing has $85,000 to invest. They can invest in Wilder Revenue at 10% compounded semiannually or at Cheapskate Investments at 9.8% compounded monthly. a. Calculate the two APYs and compare them to determine your answer. Make sure to distinguish which APY belongs to ...
April 14, 2014
Name the property of real numbers illustrated by the equation 2·(8·7)=(2·8)·7 answers are. Distributive property ,associative property multiplication, Communicative property multiplication, Associative property addition
February 23, 2014
stacey is standing 5 miles west of the control tower at an airport. A plane took off traveling directly north of the control tower at a rate of 180 mph along the ground at a constant angle of 15 degrees. A)after 12 minutes, what is the angel between Stacey and the plane along ...
February 9, 2014
A piece of wire 28 m long is cut into two pieces. One piece is bent into a square and the other is bent into a circle. (a) How much wire should be used for the square in order to maximize the total area? (b) How much wire should be used for the square in order to minimize the ...
November 5, 2013
Hi I have a maths problem I can't figure out please someone help. Zac had some 2c stamps and 5c stamps.he needed to put 30c on a postcard to mail it.what combinations of stamps could he use.
August 13, 2013
An oven is plugged into a 120 V electrical outlet and "cooks" the food by using a 144 ohm resistor light bulb that converts electrical energy to both light and heat energy. If the light bulb converts 75% of the electrical energy to thermal energy, and the oven is ...
May 30, 2013
A 5.0 ball is initially sitting at rest on top of a 41 m high hill. The ball is pushed with a force of 25 N for 3.0 s toward the edge of a hill. Upon reaching the edge, the ball is allowed to roll down the hill where it reaches the flat ground. To the nearest mile per hour, ...
May 30, 2013
A pair of dice is rolled once. suppose you lose $9 if the dice sum to 9 and win $11 if the dice sum to 4 or 6. how much should you win or lose if any other number turns up in order for the game to be fair?
October 23, 2012
Predicate and subjects
1. The smell of cooking is delicious to the hungry camper. 2. A good fire is difficult to build. looking for simple subject and predicate 1, smell. Predicate. Camper subject 2. Fire subject. Build predicate
September 30, 2012
EXTRA CREDIT QUESTION(this is like kinda really hard for me at the moment i got the first one but the others not so much) The city of Celina was ordered by the Ohio EPA in 2003 to resolve its MCL (maximum contaminant level) violations of its drinking water. The Celina water ...
April 26, 2012
I am having trouble answering this. please help! Q: Cereol is a newly discovered compound in corn flakes. A biologist suspects that it increases mental ability. She is making a solution to test on rats. First she makes a stock solution. She discovers that this is too ...
March 31, 2012
The diagonal of a square has length square root 2 X s, where s is the length of a side of the square. What is the length of the diagonal in a square with sides that are 13 cm? Round your answer to the nearest tenth.
March 7, 2012
A scientist wants to make a solution of tribasic sodium phosphate, , for a laboratory experiment. How many grams of will be needed to produce 625 of a solution that has a concentration of ions of 0.800
October 13, 2011