Answer:
There are
grams contained in all the seawater in the world.
Explanation:
At first let is determinate the total mass of seawater (
), measured in grams, in the world by definition of density and considering that mass is distributed uniformly:

Where:
- Density of seawater, measured in grams per liters.
- Volume of seawater, measured in liters.
If
and
, then:


The total mass of sodium chloride is determined by the following ratio:


Given that
and
, the total mass of sodium chloride in all the seawater in the world is:

There are
grams contained in all the seawater in the world.
Vibration?
I’m not super sure.
Answer:

Explanation:
![\Delta H_{rxn}^{0}=\sum [n_{i}\times \Delta H_{f}^{0}(product)_{i}]-\sum [n_{j}\times \Delta H_{f}^{0}(reactant_{j})]](https://tex.z-dn.net/?f=%5CDelta%20H_%7Brxn%7D%5E%7B0%7D%3D%5Csum%20%5Bn_%7Bi%7D%5Ctimes%20%5CDelta%20H_%7Bf%7D%5E%7B0%7D%28product%29_%7Bi%7D%5D-%5Csum%20%5Bn_%7Bj%7D%5Ctimes%20%5CDelta%20H_%7Bf%7D%5E%7B0%7D%28reactant_%7Bj%7D%29%5D)
Where
and
are number of moles of product and reactant respectively (equal to their stoichiometric coefficient).
is standard heat of formation and
is standard enthalpy change for reaction at 
So, ![\Delta H_{rxn}=[3mol\times \Delta H_{f}^{0}(CO_{2})_{g}]+[4mol\times \Delta H_{f}^{0}(H_{2}O)_{g}]-[1mol\times \Delta H_{f}^{0}(C_{3}H_{8})_{g}]-[5mol\times \Delta H_{f}^{0}(O_{2})_{g}]](https://tex.z-dn.net/?f=%5CDelta%20H_%7Brxn%7D%3D%5B3mol%5Ctimes%20%5CDelta%20H_%7Bf%7D%5E%7B0%7D%28CO_%7B2%7D%29_%7Bg%7D%5D%2B%5B4mol%5Ctimes%20%5CDelta%20H_%7Bf%7D%5E%7B0%7D%28H_%7B2%7DO%29_%7Bg%7D%5D-%5B1mol%5Ctimes%20%5CDelta%20H_%7Bf%7D%5E%7B0%7D%28C_%7B3%7DH_%7B8%7D%29_%7Bg%7D%5D-%5B5mol%5Ctimes%20%5CDelta%20H_%7Bf%7D%5E%7B0%7D%28O_%7B2%7D%29_%7Bg%7D%5D)
or, ![\Delta H_{rxn}=[3mol\times -393.509kJ/mol]+[4mol\times -241.818kJ/mol]-[1mol\times -103.8kJ/mol]-[5mol\times 0kJ/mol]](https://tex.z-dn.net/?f=%5CDelta%20H_%7Brxn%7D%3D%5B3mol%5Ctimes%20-393.509kJ%2Fmol%5D%2B%5B4mol%5Ctimes%20-241.818kJ%2Fmol%5D-%5B1mol%5Ctimes%20-103.8kJ%2Fmol%5D-%5B5mol%5Ctimes%200kJ%2Fmol%5D)
or, 
It is the concept of surface tension that helps the coin to float on the top of the water in the glass. The surface tension acts just opposite to the gravitational force and that is why when any metal placed in the water it will float and come on the surface. Hope this helps!

The nucleus of an atom of the element is positively charged and atom has a hollow space inside it.
Explanation:
This experiment was conducted by Rutherford in this experiment. He placed a gold foil and surround it with a screen.
And He exposed gold foil in alpha particles rays in which he noticed that most rays passed through atom which conclude that atom has a large space, some rays get deflected and some reverse their path this show that the positive charge of nucleus of an atom.