Answer:-
,
, ![[CO_3^2^-]=0.254M](https://tex.z-dn.net/?f=%5BCO_3%5E2%5E-%5D%3D0.254M)
Solution:- We are asked to calculate the molarity of sodium carbonate solution as well as the sodium and carbonate ions.
Molarity is moles of solute per liter of solution. We have been given with 6.73 grams of sodium carbonate and the volume of solution is 250.mL. Grams are converted to moles and mL are converted to L and finally the moles are divided by liters to get the molarity of sodium carbonate.
Molar mass of sodium carbonate is 105.99 gram per mol. The calculations for the molarity of sodium carbonate are shown below:

= 
So, molarity of sodium carbonate solution is 0.254 M.
sodium carbonate dissociate to give the ions as:

There is 1:2 mol ratio between sodium carbonate and sodium ion. So, the molarity of sodium ion will be two times of sodium carbonate molarity.
= 0.508 M
There is 1:1 mol ratio between sodium carbonate and carbonate ion. So, the molarity of carbonate ion will be equal to the molarity of sodium carbonate.
![[CO_3^2^-]=0.254M](https://tex.z-dn.net/?f=%5BCO_3%5E2%5E-%5D%3D0.254M)
<h3>
Answer:</h3>
23.95 °C
<h3>
Explanation:</h3>
We are given;
- Mass of the sample is 0.5 gram
- Quantity of heat released as 50.1 Joules
- Specific heat capacity is 4.184 J/g°C
We are required to calculate the change in temperature;
- Quantity of heat absorbed is given by the formula;
- Q = mass × specific heat capacity × Change in temperature
That is, Q = mcΔT
Rearranging the formula;
ΔT = Q ÷ mc
Therefore;
ΔT = 50.1 J ÷ (0.5 g × 4.184 J/g°C)
= 23.95 °C
Therefore, the expected change in temperature is 23.95 °C
Answer:
A Valence electron are the electrons in the outermost shell or energy level of an atom.