Answer:
i have to say whether its correct or wrong yep
The right answer is
2) NaCl
In fact, from the definition of acid, all acids contain at least one atom of hydrogen. In the options given by the problem, all compounds contain at least one atom of hydrogen H, except for the NaCl: therefore, NaCl is not an acid.
Answer:
151.2 m/s
Explanation:
m1 = 0.020 kg
m2 = 2.5 kg
vf = 1.2 m/s
m1v1 +m2v2 = (m1 +m2)vf
0.020v1 + 0 = (0.020 +2.5)(1.2)
---> 151.2 m/s
Answer:
![T=51.64^\circ F](https://tex.z-dn.net/?f=T%3D51.64%5E%5Ccirc%20F)
![t=180.10s](https://tex.z-dn.net/?f=t%3D180.10s)
Explanation:
The Newton's law in this case is:
![T(t)=T_m+Ce^{kt}](https://tex.z-dn.net/?f=T%28t%29%3DT_m%2BCe%5E%7Bkt%7D)
Here,
is the air temperture, C and k are constants.
We have
in
So:
![T(0)=70^\circ F\\T(0)=10^\circ F+Ce^{k(0)}\\70^\circ F=10^\circ F+C\\C=70^\circ F-10^\circ F=60^\circ F](https://tex.z-dn.net/?f=T%280%29%3D70%5E%5Ccirc%20F%5C%5CT%280%29%3D10%5E%5Ccirc%20F%2BCe%5E%7Bk%280%29%7D%5C%5C70%5E%5Ccirc%20F%3D10%5E%5Ccirc%20F%2BC%5C%5CC%3D70%5E%5Ccirc%20F-10%5E%5Ccirc%20F%3D60%5E%5Ccirc%20F)
And we have
in
, So:
![T(30)=60^\circ F\\T(30)=10^\circ F+(60^\circ F)e^{k(30)}\\60^\circ F=10^\circ F+(60^\circ F)e^{k(30)}\\50^\circ F=(60^\circ F)e^{k(30)}\\e^{k(30)}=\frac{50^\circ F}{60^\circ F}\\(30)k=ln(\frac{50}{60})\\k=\frac{ln(\frac{50}{60})}{30}=-0.0061](https://tex.z-dn.net/?f=T%2830%29%3D60%5E%5Ccirc%20F%5C%5CT%2830%29%3D10%5E%5Ccirc%20F%2B%2860%5E%5Ccirc%20F%29e%5E%7Bk%2830%29%7D%5C%5C60%5E%5Ccirc%20F%3D10%5E%5Ccirc%20F%2B%2860%5E%5Ccirc%20F%29e%5E%7Bk%2830%29%7D%5C%5C50%5E%5Ccirc%20F%3D%2860%5E%5Ccirc%20F%29e%5E%7Bk%2830%29%7D%5C%5Ce%5E%7Bk%2830%29%7D%3D%5Cfrac%7B50%5E%5Ccirc%20F%7D%7B60%5E%5Ccirc%20F%7D%5C%5C%2830%29k%3Dln%28%5Cfrac%7B50%7D%7B60%7D%29%5C%5Ck%3D%5Cfrac%7Bln%28%5Cfrac%7B50%7D%7B60%7D%29%7D%7B30%7D%3D-0.0061)
Now, we have:
![T=10^\circ F+(60^\circ F)e^{-0.0061t}(1)](https://tex.z-dn.net/?f=T%3D10%5E%5Ccirc%20F%2B%2860%5E%5Ccirc%20F%29e%5E%7B-0.0061t%7D%281%29)
Applying (1) for
:
![T=10^\circ F+(60^\circ F)e^{-0.0061*60}\\T=10^\circ F+(60^\circ F)0.694\\T=10^\circ F+41.64^\circ F\\T=51.64^\circ F](https://tex.z-dn.net/?f=T%3D10%5E%5Ccirc%20F%2B%2860%5E%5Ccirc%20F%29e%5E%7B-0.0061%2A60%7D%5C%5CT%3D10%5E%5Ccirc%20F%2B%2860%5E%5Ccirc%20F%290.694%5C%5CT%3D10%5E%5Ccirc%20F%2B41.64%5E%5Ccirc%20F%5C%5CT%3D51.64%5E%5Ccirc%20F)
Applying (1) for
:
![30^\circ F=10^\circ F+(60^\circ F)e^{-0.0061t}\\30^\circ F-10^\circ F=(60^\circ F)e^{-0.0061t}\\-0.0061t=ln(\frac{20}{60})\\t=\frac{ln(\frac{20}{60})}{-0.0061}=180.10s](https://tex.z-dn.net/?f=30%5E%5Ccirc%20F%3D10%5E%5Ccirc%20F%2B%2860%5E%5Ccirc%20F%29e%5E%7B-0.0061t%7D%5C%5C30%5E%5Ccirc%20F-10%5E%5Ccirc%20F%3D%2860%5E%5Ccirc%20F%29e%5E%7B-0.0061t%7D%5C%5C-0.0061t%3Dln%28%5Cfrac%7B20%7D%7B60%7D%29%5C%5Ct%3D%5Cfrac%7Bln%28%5Cfrac%7B20%7D%7B60%7D%29%7D%7B-0.0061%7D%3D180.10s)