Science & Mathematics - 8 November 2007

a) For a liquid to have a vapor pressure, rate of condensation must be greater than rate of evaporation.

b) Substances with large molar masses have relatively low vapor pressures.

c) An increase in temperature will increase the vapor pressure of a liquid

d) Temperature changes during a phase change.

e) For ice to float in water, it's density must be less than that of water.

2007-11-08 15:47:10 · 3 answers · asked by Anonymous in Chemistry

We need to give our dog a shot.. but me and my mom don't know what CC means, we were told to give her 2 Cm but all there is on the syrynge is units and CC. HELP

2007-11-08 15:46:04 · 5 answers · asked by Anonymous in Mathematics

How do you rewrite a equation in function form?

2007-11-08 15:44:24 · 6 answers · asked by sammyankee 2 in Mathematics

A. 6
B. 3
C. 2
D. −2

2007-11-08 15:43:44 · 4 answers · asked by BabyGirl82985 1 in Mathematics

I need to know their names, and what makes them diferent from the other proteins.I know some names are :Integral, Peripheral, and glycoprotein, but i don't the differences or their other possible names.

2007-11-08 15:41:48 · 5 answers · asked by ¡•ziggy•¡ 3 in Biology

I'm trying to find the pH of HONH3Cl. I have .400 M and I know that it becomes:

HONH3Cl <-> NH2OH + HCl

I also know how to do an IRE (also called ICE) table, but what value do you use for Kb for the above reaction? or do you?

2007-11-08 15:40:47 · 2 answers · asked by xxsoccerchickxx_84 1 in Chemistry

make an equation of the data?

x=0 1 2 3 4 5
y=1 3 5 7 9 11

2007-11-08 15:40:19 · 8 answers · asked by Angel 1 in Mathematics

Could someone please tell me how to find acceleration when you are only given mass? Below is the force problem I am trying to solve:
A 20 kg wooden crate falls from a truck when it is traveling along a straight and level road at 25 m/s. If the crate slides for a distance of 80m in coming to rest, find acceleration.

I would appreciate it if someone would help.

2007-11-08 15:39:29 · 4 answers · asked by mangomantra 1 in Physics

2007-11-08 15:38:42 · 2 answers · asked by freeaakxii 2 in Earth Sciences & Geology

http://www.jamesrahn.com/CalculusI/Activities/LABS/trapezoidal%20rule.pdf
can someone tell me how to answer example 1 plz ??

2007-11-08 15:37:49 · 1 answers · asked by thatisme 2 in Mathematics

Find the solubility of AgI in 2.8 M NH3 [Ksp of AgI = 8.3 *10-17 and Kf of Ag(NH3)2+ = 1.7 * 107].

2007-11-08 15:36:52 · 1 answers · asked by socr8711 2 in Chemistry

P=Poe (rt)? I know that P is the population (I am assuming that (rt) could be annual growth rate)....can someone please fill in the rest for me? Or if I have written it down incorrectly, please correct it =)

We know that 6.6 x 10 (to the ninth power) is our current population...
We know that .455% is a conservative rate of annual growth...

Please help me with the rest...Thanks

2007-11-08 15:35:23 · 1 answers · asked by cbmultiplechoice 5 in Mathematics

I never thought about this...until psi mentioned ghosts could be about good things too.

2007-11-08 15:34:49 · 9 answers · asked by Deenie 6 in Paranormal Phenomena

i have been out of school for years and forgot how to do these algerbraic experssions so someone please refresh my brain please

2007-11-08 15:32:08 · 7 answers · asked by Brooklyn B 1 in Mathematics

How much heat (kJ) is required to completely melt 30.5 grams of ice at 0 oC ?

anddddd

Which of the following are true statements ?



a) The triple point of H2O is -4oC and 4.58 atm

b) At 5 atm and −78oC solid CO2 will not sublime

c) The freezing temperature of a substance is less dependent on pressure than is its boiling boint

d) At 20 atm and −78oC CO2 is in the liquid phase

2007-11-08 15:29:05 · 4 answers · asked by matt b 1 in Chemistry

2*sqrt(5) + sqrt(6)
---divided by------
sqrt(6) - sqrt(5)

Please help, I have no idea how to do this.

2007-11-08 15:28:24 · 7 answers · asked by DoWHATiDO 3 in Mathematics

2007-11-08 15:26:18 · 2 answers · asked by Anonymous in Earth Sciences & Geology

A mixture of 10 cm^3 of methane and 10 cm^3 of ethane was mixed with an excess of oxygen and the mixture was ignited. After cooling to room temperature, the residual gas was passed through a solution of potassium hydroxide. What was the volume of the gas absorbed by the alkali?

(1) 15 cm^3
(2) 20 cm^3
(3) 25 cm^3
(4) 30 cm^3

The answer is (4) 30 cm^3...I don't understand...Can you show me the workings and with explanation too? Thanks a lot.

2007-11-08 15:24:09 · 3 answers · asked by ♪£yricảl♪ 4 in Chemistry

1. Explain how to use parallax to measure the distance to objects. (I understand what the question's saying, but I don't get what parallax exactly is...)

2. Where are elements heavier than hydrogen and helium made? (I can't find it in the book!)

3. What causes a star to die?

2007-11-08 15:22:06 · 3 answers · asked by markiepeanut 2 in Astronomy & Space

I would like to cross different coloured hypiastrums to produce varied colours. Is it possible to do this or do i need sophfiscated equipment.

2007-11-08 15:21:40 · 2 answers · asked by peter s 1 in Botany

double integration of log(x^2+y^2)dxdy between 0toa and 0 to squareroot(a^2-y^2) a>0

2007-11-08 15:20:19 · 2 answers · asked by rajamani n 1 in Mathematics

The relative atomic mass of an element with atomic number 10 is 20.2. The element consists of two isotopes, the nuclei of which contain 10 and 12 neutrons respectively. The ratio of the relative abundance of the lighter to heavier atoms is ______

(1) 1 : 9
(2) 9 : 1
(3) 1 : 4
(4) 4 : 1

The answer is (2) 9 : 1... i don't understand...please show me your workings.. and explain too..thanks.

2007-11-08 15:19:09 · 2 answers · asked by Anonymous in Chemistry

Find the Laplace transform of f(t)=[e^(-2t)]cosh(3t)

Find the Laplace inverse transform of F(s)=(s+2)^2/(s+3)^5

And last one is Use the Laplace transform to solve the equation
y^(2)-2y^(1)+y=f(t), y(0)=y^(1)=0 where f(t) ={t^2, 0<(or equal)t<1 and 2t-1, t>(or equal) 1


I think I am just missing a step in each of these that is causing me to get a very strange answer for them. Help on any of these would be appreciated.

2007-11-08 15:18:00 · 1 answers · asked by mikey6542 1 in Mathematics

The cube is heated to 135°C from 25°C. What is the increase in the surface area of the cube? (Hint: The length of each edge of the cube expands when heated.)

2007-11-08 15:17:26 · 1 answers · asked by Anonymous in Physics

what is the difference between a speed graph and an acceleration graph? i am supposed to think abou the formulas u use when calculating each.

2007-11-08 15:16:36 · 1 answers · asked by Sarah S 3 in Physics

The specimen is heated to 95.0°C and then placed in a 0.13 kg copper vessel that contains 0.089 kg of water at equilibrium at 25.0°C. The loss of heat to the external environment is negligible. When equilibrium is established, the temperature is 27.0°C. What is the specific heat capacity of the specimen?

2007-11-08 15:16:06 · 1 answers · asked by Anonymous in Physics

2007-11-08 15:15:05 · 1 answers · asked by tibsy2007 2 in Chemistry

What do the antioxidants do to promote prevention?

2007-11-08 15:12:38 · 3 answers · asked by Anonymous in Medicine

CaO + C ----> CaC2 + CO2

2007-11-08 15:11:18 · 3 answers · asked by Amusing but confusing 3 in Chemistry

i need an understanding of this concept

2007-11-08 15:10:01 · 2 answers · asked by Anonymous in Chemistry