minx64

Calculate the pH of a 0.15 M solution of Na2CO3.

I'm not sure how to go about solving this problem.

The vapor pressure of the solution at 60degree C is 142 torr. The vapor pressure of water at 60degree C is 150. torr. What is the molar mass of the solute? Ignoring the significant figures for this problem.

Given the following data calculate the change in H for the reaction CaC2(s) + 2 H2O(l) > Ca(OH)2(aq) + C2H2(g)

data: Ca(s) + 2C > CaC2 change in H = -62.8 kJ

Ca(s) + 1/2 O2(g) > CaO(s) change in H = - 635.5 kJ

CaO(s) + H2O(l) > Ca(oh)2 (aq) change in H = -653.1 kJ

C2H2(g) + 5/2 O2(g) > 2CO2(g) + H2O(l) change in H = -1300kJ

C(graphite) + O2(g) > CO2(g) change in H = -393.51 kJ

Convert 32.8lb to g (1lb = 453.6g)

A. 7.23e-2g

B. 1.49e3g

C. 7.23e4g

D. 1.49e4g

E. 1.49e2g

Convert 0.052ft^3 to L (2.54cm=1 in, 1L = 1dm^3

A. 1.8e-3L

B. 1.5L

C. 15L

D. 1.6e-3L

E. 1.7L

How many significant numbers in 0.0006042

A. 8 B. 7 C. 4 D. 0 E. 3

Express the volume 321.0cm^3 in liters

A. 0.03210L B. 0.3210L C. 32.10L D. 3.210L E. 321.0L

The calibration points for the linear Peaumur scale are the usual melting point of ice and boiling points of water,which are assigned the values 0 degree R and 80 degree R respectively. The normal body temp of a human is 98.6*F..what is the temp in *R?

A. 28.0 B. 37.0 C. 29.0 D. none of these E. 29.6

precision of ???? Please help me understand this as this is my 1st chemistry class

3(x+3)^2 = 75

Im confused on whether or not to solve as 3(x+3)^2 - 75=0 and then how to solve from there

For the life of me I cant figure out how to get this quadratic equation right

-22x + 21=8x^2

The ^2 stands for squared... thanks to anyone who can help!!

I'm having trouble with linear equations...Its been 30 years since I had algebra and am going to be taking intro to algebra in the fall semester....if anyone can help it would be greatly appreciated and if you could show how you arrived at your answer I'd appreciate it :-)

Thanks!!! 3x+2y=6 and 9y=x-4 and 3y+6x=-21

We've finished all the worlds in world 9...have all the coins...I had heard there's a world 9-9 to open a world 10...any truth to this?? If so then how to open 9-9

Im curious as to how many folks never got something one Christmas because they had been bad all year as a kid !!! Or any parents have you done this to your kid to get them to straighten up??? Im not talking doing this to a 5 yr old...talking kids old enough to know better...12 and up.....

Im looking for knowledgable opinions on these cars...we already own a 528i and I have an opportunity to purchase either of these cars for myself...the C320 is a 2001 and the 528i is a 2001...thanks in advance for any input