Wednesday

February 22, 2017
Total # Posts: 622

**Chemistry**

These are all true or false questions, and I think some of my answers may be wrong. Could someone please check them for me? 1) All stoichiometry calculations are based on STP conditions. (True) 2. Given the amount of reactant, you must use coefficients from the balanced ...

*June 4, 2007*

**Chemistry 3**

How is it possible for me to tell which of these solutes will produce an acidic solution when dissolved in water? LiOH CH3CO2K H2SO3 KOH NaOH NH4NO3 NaOH NaOH can't be the only one... Molecules that produce OH^- when dissolved in water will be basic. Examples:LiOH, KOH, ...

*May 24, 2007*

**Chemistry 2**

Can someone please tell me which of the following I have wrong?? I know that one or more is incorrect, but I'm not sure which ones... Match the following Bronsted acids with their conjugate bases. Choices: SO42-, SO32-, CO32-, HPO42-, HPO32-, Cl-, F-, NO3-, NO2-, HSO4-, ...

*May 24, 2007*

**Chemistry**

In a titration experiment 34.12 mL of 0.902 M KOH is reacted with H2SO4. The endpoint is reached when 50.46 mL of the acid is mixed with the base. What is the molar concentration of the acid? I'm having a hard time even starting this problem, since I don't know the ...

*May 24, 2007*

**Algebra 2 once more**

I have more answers that I would like checked. Also, there is one that I'm really confused about. I appreciate any help. :) Rewrite as the log of a single number. 1) 8 ln 2 = ln(2^8) 2) log 42 - log 6 = log 36 (I think this one may be wrong). Evalute each expression w/o a ...

*May 23, 2007*

**More Algebra 2**

It would be great if, again, someone would check these answers for accuracy. I'd like to know if I'm doing them right. 1) What equation defines an exponential decay function? a) y=x^pi b) y=pi^-x c) y=(1/pi)^-x d) y=pi times x I think the answer is c. 2) Suppose a lake...

*May 23, 2007*

**Algebra 2**

Can someone please check these answers for me?? I'm pretty sure most of them are right, except for maybe the second T/F question... 1) T or F. The domain of y=ln x is equal to the range of y=e (superscript x). True 2) T or F. ln(3x x y to the 3rd power) = (ln x 3) x (ln x...

*May 23, 2007*

**Chem help**

What is the pH of 0.000082 M NaOH? I know how to find the pH of an aqueous solution, but I'm not sure of the formula for this one... What one? Well my question was "What is the pH of 0.000082 M NaOH?," but n/m. I figured out how to do it. Thanks anyway.

*May 22, 2007*

**Chemistry**

Icebergs in the North Atlantic present hazards to shipping, causing the length of shipping routes to increase by about 30 percent during the iceberg season. Attempts to destroy icebergs include planting explosives, bombing, torpedoing, shelling, ramming, and painting with ...

*May 15, 2007*

**Chemistry**

A 63 gram block of an unknown metal at 88 degrees C was dropped into an insulated flask containing approx. 30 g of ice and 30 g of water at 0 degrees C. After the system had reached a steady temp. it was determined that 12.1 g of ice had melted. What is the specific heat of ...

*May 15, 2007*

**Chem...one more time**

Ok ok I swear after this I'm done asking questions. It's just that I'm trying so hard to understand all of this, but sometimes it just doesn't make sense to me! So here we go: How many J of energy must be removed when 124.0 g of steam, at a temp. of 167.0 C, is...

*May 14, 2007*

**Chemistry**

This is sort of like the one I last posted, only it asks for the final temp. instead of energy... What is the final temp. (in degrees C) after a 15.5 g piece of ice at 0 degrees C is placed into a styrofoam cup with 125.0 g of water initially at 72.0 degrees C? Assume no loss ...

*May 14, 2007*

**Chemistry**

Ethanol boils at a temp. of 78.29 degrees C. What amount of energy, in joules, is necessary to heat to boiling and then completely vaporize a 23 g sample of ethanol initially at 12 degrees C? I know that the molar enthalpy heat of vaporization is 35.56 kJ/mol and the specific ...

*May 14, 2007*

**Algebra help needed!**

Recall that on some roads, a skid mark of length L ft. indicates that a car was traveling at least s mph, where s is approx. 2 times the square root of 5L. If a car stopped quickly from a speed of 55 mph, about how long would the skid marks be? Please note that we don't do...

*May 3, 2007*

**Chem help!!**

A rock salt (NaCl), ice, and water mixutre is used to make homemade ice cream. How many grams of rock salt must be added to lower the freezing point 10.0 degrees C? I have no idea what to do, please help! delta T = Kf*i*m delta T = 10. Kf is the molal freezing point constant, ...

*May 3, 2007*

**Chemistry URGENT**

I have to match the items to the statements below, and I'm stuck! My answers are in parentheses, but I know that some of them are wrong. Please help if you know how...I would GREATLY appreciate it! A Dilute B Unsaturated C Saturated D Supersaturated 1. Sodium acetate ...

*April 24, 2007*

**Chemistry**

I have to match the items to the statements below, and I'm stuck! A Dilute B Unsaturated C Saturated D Supersaturated 1. Sodium acetate solution after the excess solute fell out of solution. 2. There is visible solute on the bottom of the container. 3. The solution will ...

*April 24, 2007*

**Physics**

Use kx=mg+ma 857x = (5.9*9.8) + (5.9*.81) thus, x= .073

*March 29, 2007*

**chemistry check**

1)A pocket of gas is discovered in a deep drilling operation. The gas has a temperature of 480c and is at a pressure of 12.8 atm. What volume of gas is required to provide 18.0 L of gas at the surface where the conditions are 22 C and 1.00 atm? is this correct for number 1? ...

*March 25, 2007*

**science**

Hi I have 2 questions I hope someone can help me :) 1)A pocket of gas is discovered in a deep drilling operation. The gas has a temperature of 480c and is at a pressure of 12.8 atm. What volume of gas is required to provide 18.0 L of gas at the surface where the conditions are...

*March 25, 2007*

**Math**

Question 1 : We would like to test 3 different treatments on a particu- lar type of plant. A worker at the local greenhouse will allow us to use 3 among 10 plants. Note: Each treatment will be used on one and only one plant. a) In how many different ways can we assign the ...

*September 25, 2006*

**physics**

Given that the distancef rom Earth to the Moon is 3.8 x 10^8 m, that the Moon takes 27 days to orbit Earth, and that the mass of the Moon is 7.4 x 10^22 kg, what is the acceleration of the Moon and the size of the attractive force between Earth and Moon? Use v = (2pir)/T, ...

*September 18, 2006*