Total # Posts: 1,451
Determine the entropy change for the following displacement reaction. Cl2(g) + PbBr2(aq) → PbCl2(aq) + Br2(l). DS: (J/K mol) Cl2(g) 223.066; PbBr2(aq) 182.7; PbCl2(aq) 131.3; Br2(l) 152.231
August 6, 2010
Hi, could you please tell me if these 2 sentences are correc. Each of the twins has a doll in their room. 2. The couple have gone on vacation. Also, when you have neither....nor, you use has don't you? Example Neither Helen nor Sarah has finished their homework.
July 12, 2010
Salisbury High School decided to take their students on a field trip to a theme park. A total of 150 people went on the trip. Adults pay $45.00 for a ticket and students pay $28.50 for a ticket. How many students and how many adults went to the park if they paid a total of $4770
July 6, 2010
When genetically engineering an organism, a plasmid a. is the main chromosome of the bacteria that is cloned. b. is cut with a restriction enzyme to accept the gene of interest. c. helps screen for cells that did not take up the gene of interest. d. combines with the gene of ...
July 5, 2010
Can someone please check the errors I have noted and let me know if they see more? I am supposed to find 20 errors but can only find 15!! Please help. The correction is in parentheses. Why are great numbers of students choosing to pursue their college degrees using their home ...
July 1, 2010
(2 people talking to each other) "?Comen tus amigos contigo todos los dias?" "Si,_____ comen conmigo." a. nunca b. por la noche c. siempre d. manana C? There is a line above A in dias and a squiggly line above the first N in manana. Sorry about the ...
June 18, 2010
El profesor _____,y el estudiante _____. a. termina las clase/empieza la clase b. ensena/estudia c. ensenar mucho/estudiar d. empieza la clase/terminar I think B? There are squiggly things over the N's in ensena and ensenar.
June 17, 2010
Right triangle ABC is similar to triangle XYZ, because angle B is congruent to angle Y. If side AB equals 12 inches, side BC equals 27 inches, and side YZ equals 9 inches, then what is the length of side XY?
June 9, 2010
create a balanced chemical equation and state the type of reaction. Zinc metal reacts with aqueous silver nitrate to produce solid silver and an aqueous solution of zinc nitrate. please go step by step, would be very helpful.
May 29, 2010
The most abundant isotope of the element nobellum has a half-life of 58 minutes. After 174 minutes the sample has a mass of .300 mg. What was the orignal mass of the sample? A. 1.20 mg B. 4.80 mg C. .600mg D. 2.40 mg
May 23, 2010
i believe it would be 56.52 (not 100% positive though) because if the radius is 6, then the circumference would be 3.14(6^2)= 3.14(36) which is 113.04 then you would put that over 360 and set up a proportion: 113.04/360 = x/180 (simplified to 20347.2/360) which gives you a ...
May 17, 2010
each week, mandy's algebra teacher gives a 10 point math quiz. after 5 weeks, mandy has earned a total of 36 points for an average of 7.2 points per quiz. she would like to raise her average to 9 points. on how many quizzes must she score 10 points in order to reach her goal?
May 17, 2010
How would you use classical conditioning, operant conditioning, and observational learning to improve your academic performance? Give one example for each type of learning.
April 18, 2010
In mitosis, what is the size of a daughter cell relative to the size of the parent cell? If an onion cell has 10 chromosomes, how many double chromosomes does an onion cell have at the start of metaphase? Thanks!
April 2, 2010
Which of these is true about the following reaction? NaOH + HCl ¡æ NaCl + H2O A. NaOH is the proton acceptor. B. HCl acts as the Br©ªnsted-Lowry acid. C. NaOH and HCl are the products. D. This is an example of a neutralization reaction. E. The products ...
March 29, 2010
How much heat is given off when 24.0 g of methane is burned in air? The equation for the reaction is: CH4 + 2O2 => CO2 + 2H2O + 890 kJ What equation or formula should I use to solve this? Thanks!
March 29, 2010
SCIENCE: GR.10 OPTICS CONVEX MIRRORS
A convex security mirror has a focal length of -0.25m. A person with a height of 1.5m is 4m from the mirror. calculate the image distance and image height. AND An object 0.4m tall is placed 2.5m in front of a convex mirror that has a focal length of -90cm. Calculate image ...
March 28, 2010
A cosmetic mirror is 50cm from your face and the magnified image of your face is upright. You are told that the focal length of the mirror is 45cm. Explain why this focal length is not possible. I understand that the image would be magnified and upright...that's about it
March 28, 2010
A rectangular piece of gold is 3.1 cm long and 3 cm wide. Resistivity of gold is 2.4*10^-8. How deep is the piece when it displays a resistance of R = 1.65 μω for a current that flows along the depth-direction? I used R=(p*l)/A and solved for l. I got the answer ...
March 8, 2010
The formula for Simple Interest is Interest= Principle x Rate x Time. You fill in the formula- ?= 7540 x 4.5% x 10. Then, you turn the rate into a fraction- 0.045. Fill in the formula again, 7540 x 0.045 x 10, you multiply. 7540 x 0.045 x 10 = 3393. The interest after ten ...
March 1, 2010
I'm doing a problem, and it says "Robert has a piece of twine that is 3/4 yard long. He needs a piece of twine that is 2/3 of this length. How long of a piece of twine does robert need?" Help?
December 10, 2009
How do you write repeating decimals as fractions? There's directions in my book,but I don't understand it? For example, how would you write as a fraction 0.81 with the 81 repeating?
December 7, 2009
To suck water up a straw to a maximum height of 187 mm, what minimum gauge pressure must be produced in the lungs? Note that in order to be able to suck up water, the pressure in the lungs must be lower than the pressure outside by the exact amount of pressure created by the ...
November 25, 2009
I need to identify two arguments and define the premises and conclusion. I have to tell weather it is deductivly valid or inductivlely strong or in valid or weak and why. In the appendix 1 article Controlling Irrational Fears After 9/11. Can you help with this.
November 22, 2009
1.Explain why there is no number that can replace N to make the equation |n| = -1 true. 2. List the integers that can replace N to make the statement -|8| < n < -|-5| true. I don't really get what am I supposed to do?
November 6, 2009
to kill a mockingbird
I'm reviewing for my test about the novel "To Kill a Mockingbird". There's this question I can't answer: 1. What are the generalizations (like stereotyping) made about black people? Who makes them? And how are black people affected by it? The same ...
October 28, 2009
Ahh. The shape didn't show. Basically, it's a rectangle with like a triangle on the side of it. 15 on the top, 25 on the side with the triangle point, 20 on the right side, 15 on the bottom, where the triangle is. and 15 on the bottom of the rectangle
October 20, 2009
So, I need to find the area of this shape. It's an irregular shape, and I don't know how to figure it out. The shape looks like, 15 -------- /| | 25 / | | 20 / | | / | | /____|______| 15 15 I was told the answer was 450. Though I don't know how to figure 450 out?
October 20, 2009
The formula for the area A of the triangle is A=1/2BH, where B is the length of the base, and H is the height. Solve the equation for B. I don't know how I'm supposed to be able to figure this out?
October 16, 2009
i know these are a few questions but i just can't find them anywhere.i really need to know why the bauta mask was made,how you make one,who made it, and it's texture.if you could help me with any of these,i would be so thankful.
September 21, 2009