Tuesday

September 27, 2016
Total # Posts: 5,562

**Chemistry.**

Mg+2HCl--->MgCl2+H2 Using the balanced equation, how many moles of H2 will you make if you start with .00082 moles of Mg solid? How many grams of H2 is that?

*November 3, 2015*

**civics**

HELP ME PLEAASSEEE!!!!!!!

*November 2, 2015*

**civics**

What motivated the Founding fathers to include the phrase "to form a more perfect union" in the preamble of the U.S Constitution?

*November 2, 2015*

**civics**

I think its B

*November 2, 2015*

**Physics**

A curling stone with a mass of 18 kg slides 38m across a sheet of ice in 8.0 s before it stops because of friction. What is the co¨efficient of kinetic friction between the ice and the stone? (Note: you will need to calculate the acceleration of the stone first.) I solved ...

*October 29, 2015*

**Physics**

An object initially at rest experiences an acceleration of 9.8 m/s^2. How much time will it take to achieve a velocity of 58 m/s?

*October 28, 2015*

**Chemistry! HELP**

A chemistry student used the symbol "sx" to represent an s orbital that lies along the x-axis. Is this reasonable. Justify your answer.

*October 28, 2015*

**Chemistry! HELP**

What information about an electron in an atom is given by the following quantum numbers? 2px+1/2 Answer? (idk if this is right) : An electron located in the p orbital in the 2nd main enrgy level would be said to be located in the 2p sublevel.

*October 28, 2015*

**physics**

A 214-kg crate rests on a surface that is inclined above the horizontal at an angle of 19.4°. A horizontal force (magnitude = 541 N and parallel to the ground, not the incline) is required to start the crate moving down the incline. What is the coefficient of static ...

*October 28, 2015*

**Reading**

Did you find the answer to the question yet?

*October 23, 2015*

**Pre-calculus**

Thanks, Ms.Sue! You are amazing!

*October 19, 2015*

**Pre-calculus**

I have (x,y,z)=(-5a-15,-a-5,a)

*October 19, 2015*

**Pre-calculus**

Solve the system of linear equations and check any solutions algebraically. (If there is no solution, enter NO SOLUTION. If the system is dependent, express x, y, and z in terms of the parameter a.) x-3y+2z=21 5x-13y+12z=81 I have an answer but i'm not sure if it's ...

*October 19, 2015*

**physics**

The drawing shows four point charges. The value of q is 1.4 μC, and the distance d is 0.86 m. Find the total potential at the location P. Assume that the potential of a point charge is zero at infinity

*October 16, 2015*

**English**

I'm just looking for some ideas for an essay on a Tale of Two Cities.... it can be anything related to the book... and I'm not asking you to do my schoolwork for me... I can develop the thesis and points but I just need some ideas... this is for a 4u course and I ...

*October 14, 2015*

**Chemistry**

doesnt the concentration come into play some how?

*October 12, 2015*

**Chemistry**

When 22.3 mL of 1.00 M AgNO3 is mixed with 21.7 mL of 1.50 M NaCl, the temperature of the mixture rises for 21.6 degrees C to 29.7 degrees C. The mass of the aqueous mixture is 45.9 grams and its specific heat capacity is 3.94 J/grams degrees C. I calculated (45.9g)x (3.94J/g ...

*October 12, 2015*

**College Algebra**

A train leaves New York for Boston, 200 miles away, at 3:00 P.M. and averages 70 mph. Another train leaves Boston for New York on an adjacent set of tracks at 4:00 P.M. and averages 55 mph. At what time will the trains meet? (Round to the nearest minute.)

*October 12, 2015*

**Science**

A hypothetical element has two main isotopes with mass numbers of 56 and 59. If 61.00% of the isotopes have a mass number of 56 amu, what atomic weight should be listed on the periodic table for this element?

*October 12, 2015*

**functions and trig**

write the transformation of X cubed if it is shifted right four units and then reflected over the X axis

*October 12, 2015*

**Pre-calculus**

STEVE YOU THE MAN! THANK YOU!

*October 11, 2015*

**Pre-calculus**

Complete the table assuming continuously compounded interest. (Round your answers to two decimal places.) Initial Investment: Annual % Rate: Time to Double: 8 yr Amount After 10 Years: $1700 I don't understand how to get in the initial investment of annual % rate given ...

*October 11, 2015*

**Algebra**

Determine a polynomial function of degree 3 with real coefficients whose zeros are ƒ{2, 1+i .

*October 10, 2015*

**Chemistry**

yes I need to find delta H. I calculated (45.9g)x (3.94J/g Celsius) x (8.1 Celsius), which came out to 1464.8526 Joules. How do I use this into solving for Delta H?

*October 10, 2015*

**Chemistry**

yes I need to find delta H. I calculated (45.9g)x (3.94J/g Celsius) x (8.1 Celsius), which came out to 1464.8526 Joules. How do I use this into solving for Delta H?

*October 10, 2015*

**Chemistry**

When 22.3 mL of 1.00 M AgNO3 is mixed with 21.7 mL of 1.50 M NaCl, the temperature of the mixture rises for 21.6 degrees C to 29.7 degrees C. The mass of the aqueous mixture is 45.9 grams and its specific heat capacity is 3.94 J/grams degrees C

*October 10, 2015*

**Biology**

In phylogenetics, we use the terms monophyletic, polyphyletic, and paraphyletic. What do each of these terms mean? How might the concept of shared, derived traits fit with these terms? I know what each of the terms mean. I am not sure about the second question.

*October 8, 2015*

**Biology**

What are the three conditions that must be met for natural selection to occur? What should happen if those three conditions are met? Define each type of natural selection, and describe what you expect to happen over time if these types of natural selection occur. Do these ...

*October 8, 2015*

**Biology**

Why is the Hardy-Weinberg Theorem useful for studying evolutionary change? What are the assumptions of this model? How does it work (in other words, describe the procedure which is used and how you figure out genotype frequencies)?

*October 8, 2015*

**Science**

I think 7 is b

*October 7, 2015*

**Science**

I need help with this too :/

*October 7, 2015*

**Algebra**

A 52 in. board is cut into two pieces. One piece is three times the length of the other. Find the length of the other piece.

*October 7, 2015*

**Physics **

A ball of mass 0.6 kg, initially at rest, is kicked directly toward a fence from a point 20 m away. The velocity of the ball as it leaves the kicker's foot is 17 m/s at angle of 45 degrees above the horizontal. The top of the fence is 6m high. The ball hits nothing while ...

*October 6, 2015*

**Chemistry**

I figured out I went wrong when calculating the moles of hydrogen. I used the molar mass of just one hydrogen since I was calculating the moles of one mole of hydrogen. I didn't know that I had to 2X the g/mol of hydrogen. Is there an explanation why this is?

*October 5, 2015*

**Chemistry**

Oh sorry, the question also gives this information:the 0.2041g of H2O were also produced.

*October 5, 2015*

**Chemistry**

A 0.1592g sample of a hydrocarbon upon combustion analysis produces 0.5008g CO2. Its molar mass is found in another experiment to be 70g mol. Determine the empirical formula, and its molecular formula. I completely messed up this question, and I don't know where I wen'...

*October 5, 2015*

**World History**

Thanks Reed :)

*October 5, 2015*

**World History**

I have to write a paper about the the similarities and differences of Ancient China and Persia. Anyone know any good websites I could use for research?

*October 5, 2015*

**Algebra**

A luxury car rental company charges $150 per day in addition to a flat fee of $50 for insurance. Write an equation that represents the cost, f(x), (in dollars) to rent the car for x days. This equation should be in slope-intercept form.

*October 3, 2015*

**algebra**

solve the system using elimination 2x-5y=8 x-3y=-1 please explian step by step

*September 28, 2015*

**Chemistry**

4.760 g of a substance (containing only C, H, and O) is burned in a combustion analysis apparatus. The mass of CO2 produced is 1.276×101 g, and the mass of H2O produced is 3.134 g. What is the empirical formula of the compound? I keep getting CH5O2, which is incorrect!

*September 28, 2015*

**Calculus**

Let u=f(r) and r=|x|=((x1)^2 +···|(xn)^2)^1/2. Show that ∑ (∂u/∂xj)^2 = (f′(r))^2 Please help! it's an assignment due tomorrow

*September 27, 2015*

**Chemistry**

Q: 26.30mL of 0.1105 mol/L H3PO4 solution is neutralized by 139.50 mL of KOH. Calculate the mass of solid KOH required to prepare 500.0 mL of this solution. In the previous part of this question, it asked the concentration of KOH and I worked it out to be concentration of KOH ...

*September 25, 2015*

**Physics**

An incline is divided into 6 equal lengths. Starting from rest a ball accelerates down the incline. It takes 0.21 seconds to reach the first tape marker, a distance of 0.15 meter.

*September 25, 2015*

**Physics**

A student drops a rock from a bridge to the water 12.0 meters below. With what speed does the rock hit the water?

*September 24, 2015*

**phyics**

A car takes 11 s to go from v=0m/s to v = 22 m/s at constant acceleration. If you wish to find the distance traveled using the equation d=1/2at2, what value should you use for a? Express your answer to two significant figures and include the appropriate units. please help me ...

*September 20, 2015*

**phyics**

A dart leaves the barrel of a blowgun at a speed v. The length of the blowgun barrel is L. Assume that the acceleration of the dart in the barrel is uniform. a) Show that the dart moves inside the barrel for a time of 2L/v Express your answer in terms of the variables L and v...

*September 20, 2015*

**Physics**

Two hikers are climbing up a mountain and one throws a first aid kit up to another at an initial velocity of 11 m/s and at an angle of 62 deg above the horizontal. At the moment it is caught, the vertical speed is zero. What is the difference in height between the two climbers...

*September 17, 2015*

**math**

So take 1 2/5 and convert it into an improper fraction. Then multiply your improper fraction by 1/5 to see how much the second garden will need. Finally add the two numbers together

*September 17, 2015*

**History**

Imagine that you are Thomas Jefferson. You receive a letter from someone living in the colonies who does not understand what natural rights are, or how the King of England has violated them. Help please and thank you!

*September 17, 2015*

**History**

Life, Liberty and Pursit of happiness?!?

*September 17, 2015*

**History**

Yeah. But how would I put this in a sentence?

*September 17, 2015*

**History**

According to the Declaration of Independence, what are the three natural rights that are guaranteed to people? Can you help me with this question?

*September 17, 2015*

**History**

To be honset. I don't understand what those mean

*September 17, 2015*

**History**

Life, Liberty and the pursuit of Happiness.

*September 17, 2015*

**History**

Natural rights are rights that cannot be taken away by a government.

*September 17, 2015*

**History**

Examples of natural rights in declaration of independence! Please Help

*September 17, 2015*

**math,**

A jeweler is heating a gold bar. It takes 7 joules of heat to raise the temperature of the bar 1°C. The initial temperature of the bar is 25°C. Use this information for Items 4–11. 4. Make a table that shows how many joules of heat would be required to raise the ...

*September 16, 2015*

**Grammar**

Is this correct grammar? Sarah has 6 oranges. Ted has 7 oranges. How many oranges do they have altogether?

*September 16, 2015*

**math**

A jeweler is heating a gold bar. It takes 7 joules of heat to raise the temperature of the bar 1°C. The initial temperature of the bar is 25°C. Use this information for Items 4–11. 4. Make a table that shows how many joules of heat would be required to raise the ...

*September 16, 2015*

**algebra**

A jeweler is heating a gold bar. It takes 7 joules of heat to raise the temperature of the bar 1°C. The initial temperature of the bar is 25°C. Use this information for Items 4–11. 4. Make a table that shows how many joules of heat would be required to raise the ...

*September 16, 2015*

**Chemistry**

The number of moles and the mass of oxygen formed by the decomposition of 1.252 g of mercury(II) oxide. I don't understand how to solve this, just want someone to explain. Thank you!

*September 15, 2015*

**english**

What public health issue starts the escalation of misery in top of the food chain?

*September 15, 2015*

**U.S history\**

so far I have this im not sure if this is right because im supposed to follow the outline The impact of the South Atlantic slave trade system on the British North American colonies was the way it affected the colony politically and economically. Politically the colony was ...

*September 14, 2015*

**U.S history\**

I have to make a thesis statment - Prompt: Analyze the Impact of the Atlantic System on the development of the British North American colonies during the 17th and 18th centuries. Reminder: X. However, A, B, C. Therefore, Y. Tips: X= least important cause or consequence with ...

*September 14, 2015*

**U.S history\**

how did the south atlantic slave trade not change north american colonies

*September 14, 2015*

**history**

X= least important cause or consequence with explanation why A,B, C = least important cause or consequence, with explanation why Y= your assertion statement can someone plz explain what the thesis formula means and how to use it my topic is Analyze the Impact of the Atlantic ...

*September 14, 2015*

**english**

What does frivolity mean in this sentence After a year of serious work, Mr. David's grade 8 class enjoyed the frivolity of a party.

*September 13, 2015*

**science**

Suppose you are hiking along a trail. Make a comparison between your displacement and your distance traveled. Check all that apply. -Your displacement must be less than your distance traveled. -Your displacement must be greater than your distance traveled. -Your displacement ...

*September 12, 2015*

**math - ms sue**

ms. sue i need your help

*September 12, 2015*

**math**

please help, it's urgent. thanks

*September 12, 2015*

**math**

sorry, another typo, 18y should be 18x

*September 12, 2015*

**math**

sorry ignore " Write the equations and find the point of intersection." in the problem.

*September 12, 2015*

**math**

Austin is creating a new trail mix by combining two of his bestselling blends. A pineapplecoconutmacadamia (pcm) mix that sells for $18/kg&...

*September 12, 2015*

**algebra**

A medical rescue helicopter is flying at an average speed of 172 miles per hour toward its base hospital. At 2:42 p.m., the helicopter is 80 miles from the hospital. Use this information for Items 4–6. 4. Which equation can be used to determine m, the number of minutes it...

*September 10, 2015*

**Math**

Lockers are numbered with consecutive positive integers beginning with 1, and the digit 2 is used exactly 106 times (including on the last locker). What is the number of the last locker?

*September 4, 2015*

**chemistry**

What is the mass of 225ml of a liquid that has a density of 0.880g/ml

*September 4, 2015*

**Physical science **

A 70-kg man and a 50-kg woman are in a 60-kg boat when its motor fails. The man dives into the water with a horizontal speed of 3m/s in order to swim ashore. If he changes his mind, can he swim back to the boat if his swimming speed is 1m/s? If not, can the woman change the ...

*September 4, 2015*

**Statistics**

A list of transactions contains 100 numbers: 60 gains and 40 losses. The gains are positive numbers and the the losses are negative numbers. The units are thousands of dollars. For the 60 gains, the average is 18 and the SD is 7.5. For the losses the average is -20 and the SD...

*September 3, 2015*

**Chemistry**

I'm having trouble with knowing the relations between quantum numbers n, l, m(sub l), and m(sub s). Could you please explain?

*September 3, 2015*

**U.S. History**

I have some more. According to those who supported U.S. expansion, what would be 3 benefits of U.S. imperialism?

*September 2, 2015*

**U.S. History**

Can someone help me answer this questions? Why did a totalitarian regime rise in Germany in the 1930s? Explain at least three factors that led many Germans to embrace a totalitarian regime.

*September 2, 2015*

**math**

the following are the probabilities of selecting iteams from a bag (candy: grape ?, cherry 3/8, apple 1/4). What is the probability of selecting grape?

*September 1, 2015*

**Algbrea **

sapphire island is open 7 days a week the park has 8 ticket booth and each booth has a ticket seller from 10:00 AM to 5:00 PM on average ticket sellers work 30 hours per week write an equation that can be used to find t the minimum number of ticket sellers the park needs

*August 30, 2015*

**history**

Ok thanks

*August 30, 2015*

**history**

I still I don't understand so did the Europeans perceive themselves as the only people who had good military and was above everyone else.

*August 30, 2015*

**history**

how did the Europeans perceive themselves in the world during the1450s through the 1700s

*August 30, 2015*

**math**

Chicken was on sale for $7.95 per pound. Laurie bought small package that weighed 0.8 pound. How much did Laurie pay for the chicken?

*August 27, 2015*

**Math Functions**

Find the inverse function of f(x)=5 + \sqrt[3]{x}. so f^-1(x) equals...? I'm not sure how to approach this problem.

*August 26, 2015*

**math**

how do you turn a $13.75 into an improper fraction

*August 23, 2015*

**Chemistry **

You have 75.0 mL of a 2.50 M solution of Na2CrO4 (aq). You also have 125 mL of a 2.15 M solution of AgNO3 (aq). Calculate the concentration of NO3 when the two solutions are added together.

*August 22, 2015*

**Math**

No, I don't. I just didn't think you should subtract the 1/4 from the first 6 months.

*August 22, 2015*

**Math**

When Bruce started bowling, he won 1/4 of the games he played. Within six months, he was winning 7/16 of his games. If he improves at the same rate, what fraction of his games should he expect to win after another six months? I subtracted the 1/4 from 7/16 and came up with 3/...

*August 22, 2015*

**physics**

A helicopter flies over the arctic ice pack at a constant altitude, towing an airborne 99-kg laser sensor which measures the thickness of the ice (see the drawing). The helicopter and the sensor move only in the horizontal direction and have a horizontal acceleration of ...

*August 14, 2015*

**physics**

A 14.4-kg sled is being pulled across a horizontal surface at a constant velocity. The pulling force has a magnitude of 66.9 N and is directed at an angle of 32 ° above the horizontal. Determine the coefficient of kinetic friction

*August 14, 2015*

**Math**

sin(arctan(-3pi/4))

*August 10, 2015*

**Pre calc**

You are standing at the peak of a mountain that is 14000 feet above sea level. The angle of depression from this peak to a nearby smaller peak is 4°. On your map, these two peaks are represented by points that are 1 inch apart. If each inch on your map represents 1.2 miles...

*August 9, 2015*

**physics**

A puck is moving on an air hockey table. Relative to an x, y coordinate system at time t = 0 s, the x components of the puck's initial velocity and acceleration are v0x = +3.9 m/s and ax = +1.2 m/s2. The y components of the puck's initial velocity and acceleration are ...

*August 7, 2015*

**physics**

Suppose a car is traveling at +15.0 m/s, and the driver sees a traffic light turn red. After 0.405 s has elapsed (the reaction time), the driver applies the brakes, and the car decelerates at 6.00 m/s2. What is the stopping distance of the car, as measured from the point where...

*August 7, 2015*

**physics **

(a) What is the magnitude of the average acceleration of a skier who, starting from rest, reaches a speed of 10.5 m/s when going down a slope for 3.18 s? (b) How far does the skier travel in this time?

*August 7, 2015*