ElectricPavlov

What we have here is a failure to communicate!

z-5 = ?    is not a complete solveable mathematical equation......we need more information to find a distinct value for 'z'  or ' ? '       Sorry  

Max height t is also given by     -b/2a  of the quadratic equation>    -52/(-18) = t =  2.889 sec

 h(max) = -9 (2.889)^2 + 52(2.889) + 3 = 78.11  (feet?)

Y intercept is initial height of ball when t = 0    -9(0^2) +52(0) +3  = 3  (feet?)

As Alan showed, time in the air ends when h= 0       0 = -9(t^2)+52t+3     Using Quadratic Equation  t = 5.835 sec

Not positive

NaCl is an IONIC compound and readily dissociates in water  But stable as the solid 'salt'

H2O is a covalent polar compound but is relatively stable

Argon is a noble gas....noble gases (neon, krypton etc)  are very UN-reactive because they are stable

Clorine atoms are very reactive...chlorine is almost never found in a pure state, but rather as a compound with other elements

    So I will say Chlorine atom is the least stable config.

3 1/4 * 2 * 4 1/2

= 13/4  * 2  *  9/2  =  234/8 = 29 1/4

Aluminum molar weight  26.981 gm /mole

135 gm  / 26.981 gm/mole =5.00 moles

It takes TWO moles of aluminum per reaction   ( 2 Al  in the equation)

5 moles/ 2moles/rxn  x -1052 kj/rxn =  - 2631  kj

Same graph.....from Desmos.....

Sub in the poitns given:

3 = 2^2 + 2b +c     and

3 = 4^2 + 4b +c       Now solve for c   (Multiply first equation by -2  then add it to the second equation....you'll find c = 11)

Nice work, MathToo !

12/7  sec

Enjoy your time away!