Friday

February 5, 2016
Total # Posts: 262

**chemistry**

Lithium-6 has an atomic number of 3. How many electrons are in this isotope? A. 0 electrons B. 3 electrons C. 6 electrons D. 9 electrons I think C. 6
*November 19, 2012*

**chemistry**

Lithium-6 has an atomic number of 3. How many protons are in this isotope? A. 0 protons B. 3 protons C. 6 protons D. 9 protons I think 3
*November 19, 2012*

**chemistry**

boron-10 has an atomic number of 5. how many electrons are in this isotope? 0 electrons, 2 electrons, 5 electrons, 10 electrons. I think 10
*November 19, 2012*

**chemistry**

boron-10 has an atomic number of 5. how many neutrons are in this isotope? 0 neutrons, 2 neutrons, 5 neutrons, 10 neutrons. I say 5
*November 19, 2012*

**chemistry**

the idea of the atom was first proposed by john dalton. true or false false
*November 19, 2012*

**chemistry**

Actinides and Lanthanides are elements in group 3A. true or false I say false
*November 19, 2012*

**chemistry**

Lithium-6 has an atomic number of 3. how many neutrons are in this isotope? A. 0 neutrons, B. 3 neutrons, C. 6 neutrons, D. 9 neutrons I say B
*November 19, 2012*

**Math for Ms. Sue Or Steve**

Ms Sue, stop it with the insults! Thats not cool!
*November 14, 2012*

**chemistry**

guessed
*November 10, 2012*

**chemistry**

meant A
*November 10, 2012*

**chemistry**

What is the molar mass of hydrogen? A. 1.01 g/mol B. 11.01 g/mol C. 101.1 g/mol D. .0111 g/mol D
*November 10, 2012*

**chemistry**

How many atoms are in 3.14 mol of methane (CH4)? A. 7.56 x 1023 atoms B. 7.56 x 102 atoms C. 7.56 x 104 atoms D. 7.56 x 1024 atoms D
*November 10, 2012*

**chemistry**

What is a problem-solving technique that uses equivalent measurements in ratio form to solve problems? A. Avogadro's number B. Conversion C. Dimensional analysis D. The mole concept A
*November 10, 2012*

**chemistry**

In order to determine the number of atoms in a compound, you must know the number of atoms in a representative particle of the compound. True False i think false
*November 10, 2012*

**chemistry**

How many moles are in 4.81 x 1024 atoms Na? A. 0.799 mol Na B. 7.99 mol Na C. 481 mol Na D. 7.99 x 10-1 mol Na B
*November 10, 2012*

**chemistry**

How many atoms are in 1.14 mol of propane (C3H8)? A. 7.55 x 1023 atoms B. 7.77 x 1024 atoms C. 7.55 x 1024 atoms D. 7.55 x 1030 atoms C
*November 10, 2012*

**chemistry**

How many moles of magnesium is 1.25 x 1023 atoms of magnesium? A. 0.208 × 101 mol Mg B. 2.08 × 101 mol Mg C. 2.08 × 10 -1 mol Mg D. 20.8 mol Mg I think it would be D
*November 10, 2012*

**chemistry**

What is the gram molecular mass of C2H6? A. 8.0 g B. 30.0 g C. 40.0 g D. 50.0 g think B
*November 10, 2012*

**chemistry**

What is the gram fomula mass of calcium carbonate (CaSO4)? A. 6 g B. 136.2 g C. 230.0 g D. 235.4 g think B
*November 10, 2012*

**chemistry**

thank you
*November 10, 2012*

**chemistry**

The chemical explosive nitroglycerine has the formula C3H5(NO3)3. How many oxygen atoms are in the formula unit for this compound? A. 3 B. 6 C. 9 D. 12 C. 9
*November 10, 2012*

**chemistry**

The water molecule (H2O) is composed of 2 atoms of hydrogen and one atom of oxygen. What is the mass of one mole of water? A. 3 g B. 18 g C. 6 g D. 6.02 x 1023 g B. 18 g
*November 10, 2012*

**math**

On a cold winter day, the temperature is -10.0º C. What is the reading on the Fahrenheit scale? A. 10.0 oF B. 12.0 oF C. 13.0 oF D. 14.0 oF I say A
*November 7, 2012*

**math**

The temperature of the water around a nuclear reactor core is about 300 oC. what is this temperature in degrees Fahrenheit? A. 27 oF B. 332 oF C. 572 of D. 573 oF I say D
*November 7, 2012*

**math**

Solve the following and express the answer in scientific notation: (5.4 x 10^4) x (4.5 x 10^8) A. 2.4 x 10^10 B. 24 x 10^11 C. 24 x 10^12 D. 2.4 x 10^3 I say D
*November 7, 2012*

**Science**

The "resistant" threshold for gemifloxacin is >1 mg/L while the "resistant" threshold for sulfamethoxazole is >512 mg/L. Explain why there might be this great disparity of values in resistance thresholds (512-fold) for each antibiotic ...
*November 6, 2012*

**physics**

thanks, but how come m is not in kg?
*October 3, 2012*

**physics**

Just an explanation without numbers would be awesome, i just want to understand the correct steps to take. Thanks!
*October 3, 2012*

**physics**

Ice fishing equipment weighing 3,000 N is pulled at a constant speed V = 0.5 m/s across a frozen lake by means of a horizontal rope. If the coefficient of kinetic friction is 0.05, what is the work done (in J) by the fisherman in pulling the equipment a distance of 500 m?
*October 3, 2012*

**Chemistry**

got it thanks!
*September 19, 2012*

**Chemistry**

Another hour gone by working on this and i still can't figure it out. Im totally lost!
*September 19, 2012*

**Chemistry**

A mixture of ethane and ethene occupied 35.5 L at 1.000 bar and 405 K. This mixture reacted completely with 110.3 g of O2 to produce CO2 and H2O. What was the composition of the original mixture? Assume ideal gas behavior Im pretty sure i use dalton's law of partial ...
*September 19, 2012*

**Physics**

A tennis ball is thrown horizontally from an elevation of 20.60 m above the ground with a speed of 19.0 m/s. (a) Where is the ball after 2.00 s for the horizontal and vertical position? (b) If the ball is still in the air, how long before it hits the ground? If the ball is ...
*September 13, 2012*

**Math**

Fiind the area bounded by the parabola y^2 = 8x, the x axis and the line x=2
*August 21, 2012*

**Physics**

a quarter sits at the bottom of a wishing well where the gauge pressure reads 294 kPa. If the quarter has a diameter of 24mm, what is the total force acting on the top surface of the quarter? Note: Atmospheric pressure = 101.3
*August 20, 2012*

**Calculas**

square root of 2x
*July 24, 2012*

**Calculas**

Find the length of the curve y=ã(2x), from x=1 to x=4.
*July 24, 2012*

**chemistry**

Nitrogen-13 has a half-life of 10 minutes. Given a starting mass of 2.00 g of nitrogen-13, how many grams will remain at the end of 30 minutes?
*June 19, 2012*

**chemistry**

What is the molarity of the solution produced when 14.1 grams of ammonia is dissolved in sufficient water to prepare .100 liters of solution?
*May 22, 2012*

**calculus**

yes, i pretty sure i got it as my answer mathes the back of the book
*April 23, 2012*

**calculus,1**

we got a few examples in class but not understanding it at all
*April 23, 2012*

**calculus**

Can someone please show steps as I am having a hard time understanding. The position (in meters) of a particle is modeled by y=x^3-12.5x^2+51x-67.5, where xis in seconds. Find the max, min and point(s) of inflection.
*April 23, 2012*

**calculus,PSS**

help
*April 23, 2012*

**calculus**

This is just for study for exam coming up and says it could be worth up to 12 marks. Not understanding vry well the two
*April 23, 2012*

**calculus**

The position (in meters) of a particle is modeled by y=x^3-12.5x^2+51x-67.5, where xis in seconds. Find the max, min and point(s) of inflection.
*April 23, 2012*

**calculus**

A balloon is being filled at a rate of 4000 cm^3/min. How fast is the surface area of the ballon increasing when the radius is 125 cm? V=4/3pir^3, SA=4pir^2
*April 23, 2012*

**physics**

A certain dog whistle operates at 23.5 kHz, while another (brand X) operates at an unknown frequency. If neither whistle can be heard by humans when played separately, but a shrill whine of frequency 9200 Hz occurs when they are played simultaneously, estimate the operating ...
*April 23, 2012*

**Physics (Energy and Momentum)**

You are given V and are solving for dM/dt what do you set it equal to?
*April 17, 2012*

**physics**

what is the wave equation?
*April 16, 2012*

**physics**

FM radio signals are electromagnetic waves transmitted between frequencies of 88 MHz and 107 MHz. Find the range of wavelengths for these signals. largest___m smallest___m
*April 16, 2012*

**calculus**

Use Newtons method to find the roots of the equation 1/x=1+x^3
*April 4, 2012*

**Algebra 2**

Hi I need help. Can you show me how to solve this problem? Radical Inequalities. -2 + square root 9-5x greater than or equal to 6
*April 3, 2012*

**trig**

Find the other endpoint of the line segment with the given endpoint and mid point. 1. Endpoint:(-1, 9), midpoint: (-9, -10) 2. Endpoint: (2, 5), midpoint: (5, 1) 3. Endpoint:(9, -10), midpoint: (4, 8)
*March 28, 2012*

**Math**

Find the discriminant. Tell which conic section the graph will be. 3x^2 + 12 xy + 9y^2 + 7x -2y - 100
*March 11, 2012*

**managerial economics**

Qd=15.0-0.2P where Qd is annual quantity demanded in millions of units and P is the wholesale price. Incurred cost of $60 million. Production cost is $5/unit. (1) what is wholesale price, (2) production annually, (3) annual profit? Given this is a monopoly with an expiring ...
*February 29, 2012*

**trig**

does sec(x)tan(x)*tan(x)=[sec(x)(tan^2)x]
*February 23, 2012*

**chemistry**

what are three common ores from which copper can be extracted
*February 22, 2012*

**geometry**

How tall is a tower if it casts a shadow 65 ft long at the same time that a building 160 ft tall casts a shadow 130 ft long?
*February 16, 2012*

**Algebra**

How do you solve: (2x+1)(x-4)=0
*February 1, 2012*

**Language**

thank you
*January 30, 2012*

**Language **

3 disadvantages for town crying
*January 30, 2012*

**chemistry**

A solution was made by dissolving 10.0g of a nonvolatile nonelectrolyte compound in 100.0g of water froze at -0.93C. What is the approximate molecular weight of the substance. (for water..kf=1.86C/m) (m is molality)
*December 12, 2011*

**chemistry**

D=[mol.wt*P)/(R*T) D=(29.0 g/mol*0.97atm)/[(0.0821 atm*L/mol*K)*(303.15 K)] =1.13 g/L
*December 12, 2011*

**calculus**

Given f''(x)=5x−6 and f'(−3)=−6 and f(−3)=2. find f'(x) and f(1)
*November 19, 2011*

**physics**

A missile's trajectory takes it to a maximum altitude of 1300Km. If its launch speed is 5.9 Km/s, how fast is it moving at the peak of its trajectory? answer is in Km
*October 20, 2011*

**Physics.. please help!!!!!**

The third question is wrong...
*October 20, 2011*

**physics**

2.16km
*September 17, 2011*

**Math Help**

700-284=?
*September 13, 2011*

**Physics**

A frog in a hemispherical bowl, as shown below, just floats in a fluid with a density of 1.26*10e3 kg/m3. If the bowl has a radius of 6.16 cm and negligible mass, what is the mass of the frog?
*June 28, 2011*

**business**

Specialization
*April 20, 2011*

**social studies**

vgvg,c
*March 24, 2011*

**social studies**

describe 2 details about the life of the Incas
*March 19, 2011*

**math**

Jeff is thinking of a function machine.He says that the output is 5 when the input is 4.What are two different rules that he could be thinking of.
*March 10, 2011*

**physics**

train is approaching the station at a speed of 20m.s sounds a 220 hz horn. What frequency does an observer on the station platform hear
*February 28, 2011*

**physics**

What do we know? r=6.38x10^6m T=1 day=86,400s Part A: T=2(pi)r/V ==> V=2(pi)r/T a=V^2/r (Plug & chug) Part B: Now, what do we know? Only T=1 day=86,400s. We no longer know r. Latitude we'll say is represented by "l". So r(l) = r cos l Once you find that radius...
*February 23, 2011*

**ESSAY NEED HELP PLEASE**

I would help but I'm working on one now
*January 24, 2011*

**Physics**

A car is approach a corner too fast and locks up the brakes at point A and holds them on for 12.5 M to point B. The car then moves from point B at a constant speed and does into the corner. At Point C because the car is still going to fast it goes out of control and leave the ...
*January 20, 2011*

**chemistry**

What products are formed when sucrose is heated in an aqueous sulfuric acid solution? What role does the acid play?
*January 16, 2011*

**math**

HELP ME!!! One of your friends missed the class on scientific notation. Describe how you would explain to your friend what it means for a number to be in scientific notation and how to convert a number from standard form to scientific notation.
*January 10, 2011*

**math**

its =
*January 10, 2011*

**math**

|60|___|-60| < > =
*January 10, 2011*

**physics**

4ooN per second
*December 15, 2010*

**calculus**

Let R be the region in the first quadrant bounded by the graphs of y=e^-x, y=1/2x+1, and x=2. Then find the volume of the solid when R is revolved about each of the following lines... the x axis, y=-1, y=2, the y axis, x=-1, and x=3.
*December 15, 2010*

**Chem**

H2SO4(aq) + Ba(NO3)2(aq) = BaSO4(s) + 2HNO3(aq) overall heat gen by reaction answer is supposed to be -659.3 but I keep coming up with something else.
*December 14, 2010*

**Math 8th grade**

.02(2X-3)-0.03(3x(.2)=-.02
*December 12, 2010*

**Calculus**

I got x=10/3 and x=6
*November 16, 2010*

**Calculus**

Find the x-coordinates of all points on the graph of y = x^3 - 4x^2 + 5x at which the tangent line is parallel to 2y - 10x - 7 = 0
*November 16, 2010*

**Calculus**

Thanks
*November 16, 2010*

**Calculus**

Find the x-coordinates of all points on the graph of y=x^3 - 4x^2 + 5x at which the tangent line is horizontal.
*November 16, 2010*

**The Crucible Crossword Puzzle question **

Bitter
*October 30, 2010*

**physics grade 11**

A 4.3 kg bucket of water is raised from a well by a rope. The acceleration of gravity is 9.8 m/s2 . If the upward acceleration of the bucket is 4.6 m/s2, find the force exerted by the rope on the bucket. Answer in units of N. I'm almost sure the answer requires me to use ...
*October 17, 2010*

**physics grade 11**

A 4.3 kg bucket of water is raised from a well by a rope. The acceleration of gravity is 9.8 m/s2 . If the upward acceleration of the bucket is 4.6 m/s2, find the force exerted by the rope on the bucket. Answer in units of N. I'm almost sure the answer requires me to use ...
*October 17, 2010*

**physics**

Why do we not need to convert N into kg?
*October 13, 2010*

**Chemistry**

How many milliliters of 0.230 M Na2S2O3 solution are needed to titrate 2.349 g of I2 according to the equation below? I2(aq)+2S2O3^2-(aq)->S4O6^2-(aq)+2I^1-(aq)
*October 6, 2010*

**Chemistry**

I have the same question and that's all the information that it gives
*September 28, 2010*

**biology**

Are all mixtures solutions? Are all solutions mixtures? Give an example.
*September 9, 2010*

**Fundamentals of Cost Analysis (Economic Analysis)**

1431926
*August 19, 2010*

**Chemistry**

It is difficult to type these but I'll do my best. This is the first question and I just don't get it. My professor is out of the country so any help would be appreciated. Give the IUPAC name for each of the following alkanes: CH3 I a. CH3--CH--CH2--CH2--CH3 b. CH3 CH3...
*July 20, 2010*

**Chemistry**

This is the first in a series of hw pages. If anyone would be able to help me with this one I think I would be able to complete the other 20 hw questions I have. Thanks to anyone that helps. For each definition, find a corresponding term from the following list: alkane,alkene...
*July 20, 2010*