HELP! concentrations of ions
Homework Statement
Determine the concentration for the following ions:
H2PO4-
HPO4^2-
PO4^3- in the dissociated of 7.0M H3PO4 solution
Homework Equations
I know that the number given is a phosphoric acid and is a triprotic acid.
Concentration of atoms...
then x=33 then back to the situation where the smaller van(x) makes two trips and the question is trying to figure out what's the number of seats on the larger van.
IS THERE ANOTHER STEP BECAUSE WHEN I INPUTTED 33 AS THE ANSWER IT WAS INCORRECT.
A MORE RECENT QUESTION LIKE THIS ONE IS...
Homework Statement
A Company use two vans from 7-9am. ONE van has 9 more seat than the other. The smaller van makes two trips, and the larger van make 1 trip?
The maximum seats of both vans that was given would be 69.
Let x be the seats of small van and y be the seat of the larger van...
y=x+5
71=x+y
y=x+5
71=x+x+5
71=x2+5
-5 -5
66=x2
8.12=x
IS THIS STILL WRONG?... DO I NEED TO INCORPORATE "The smaller van makes two trips, larger 1 trip".
y=x+5
71=x+y
------------
y=x+5
-y=x-71
------------
0=x+5
0=x-71
-5-+71=76
------------- this is wrong is it
y=x+5
71=x+y
----------------------
-5=x+-y
71=x+y
66=x CORRECT IT PLease
would it be x+y=71 because x=the smaller van and y= the larger van...put them together it has a seat of 71
AND if that's the case what's after this
y=x+5
71=x+y
Homework Statement
A co. use two vans 7-9am. 1 van has 5 more seat than the other. The smaller van makes two trips, larger 1 trip?
The maximum seats of both vans that was given would be 71.
Let x be the seats of small van and y be the seat of the larger van.
How many seats does the...
6(x-y)=2400
6(440-y)=2400
2640-6y=2400
-6y=-240
y=40
well i know that:
x is the max speed of the plane :440
y is the speed of the wind:40
if i divide it its: 11...is that the answer?
opps my mistake.
6(x-y)=2400
6(480-y)=2400
2880-6y=2400
-6y=-480
y=80
is this right. So is this the answer if their no wind for the plane or is there another step to it?
So would it rate x time= distance
6(x-y)=2400 against the wind
5(x+y)=2400 with the wind
6x-6y=2400
x-y=400
y=400-x
-------------------------
5x+5y=2400
x+y=480
x-(400-x)=480
2x-400=480
2x=880
x=440
---------------------------
6(x-y)=2400
6(480-y)=2400
2880+2y=2400
2y=-480...
Homework Statement
At maximum speed, an airplane travels 2400 miles against the wind in 6hrs. Flying with the wind, the plane can travel the same distance in 5hrs.
Let x be the maximum speed of the plane and y be the speed of the wind. What is the speed of the plane with no wind.
Homework...