From other sources, the given mass of the solute that is being dissolved here is 7.15 g Na2CO3 - 10H2O. We use this amount to convert it to moles of Na2CO3 by converting it to moles using the molar mass then relating the ratio of the unhydrated salt with the number of water molecules. And by the dissociation of the unhydrated salt in the solution, we can calculate the moles of Na+ ions that are present in the solution.
Na2CO3 = 2Na+ + CO3^2-
7.15 g Na2CO3 - 10H2O (1 mol / 402.9319 g) (1 mol Na2CO3 / 1 mol Na2CO3 - 10H2O) ( 1 mol Na2CO3 / 1 mol Na2CO3-10H2O ) ( 2 mol Na+ / 1 mol Na2CO3) = 0.04 mol Na+ ions present
Answer:
Which wind blows cool air inland during the day? Sea Breeze
Which wind blows cool air toward the sea at night? Land Breeze
Which winds blow steadily from specific directions and over long distances? Global Winds
Answer:
protons
Explanation:
electron number changes when the atom reacts with another atom to gain a full octet
neutron number changes when it goes through radioactive decay
but proton number never changes
Answer: 
Explanation:

Here Mn undergoes oxidation by loss of electrons, thus act as anode. silver undergoes reduction by gain of electrons and thus act as cathode.

Where both
are standard reduction potentials.
![E^0_{[Mn^{2+}/Mn]}= -1.18V](https://tex.z-dn.net/?f=E%5E0_%7B%5BMn%5E%7B2%2B%7D%2FMn%5D%7D%3D%20-1.18V)
![E^0_{[Ag^{2+}/Ag]}=+0.80V](https://tex.z-dn.net/?f=E%5E0_%7B%5BAg%5E%7B2%2B%7D%2FAg%5D%7D%3D%2B0.80V)
![E^0=E^0_{[Ag^{+}/Ag]}- E^0_{[Mn^{2+}/Mn]}](https://tex.z-dn.net/?f=E%5E0%3DE%5E0_%7B%5BAg%5E%7B%2B%7D%2FAg%5D%7D-%20E%5E0_%7B%5BMn%5E%7B2%2B%7D%2FMn%5D%7D)

The standard emf of a cell is related to Gibbs free energy by following relation:

= gibbs free energy
n= no of electrons gained or lost = 2
F= faraday's constant
= standard emf = 1.98V

Thus the value of
is 
First convert grams to moles:
70.0g *(mole/98.079) = 0.7137mole
Remember that molarity is moles per liter:
0.7137mole *(1/280mL) *(1000mL/L) = 25.5M