Answer:- ![[Na_2CO_3]=0.254M](https://tex.z-dn.net/?f=%5BNa_2CO_3%5D%3D0.254M)
, ![[Na^+]=0.508 M](https://tex.z-dn.net/?f=%5BNa%5E%2B%5D%3D0.508%20M)
, ![[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.
![[Na^+]=2(0.254M)](https://tex.z-dn.net/?f=%5BNa%5E%2B%5D%3D2%280.254M%29)
= 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.
Explanation:
Let the volume of the solution be 100 ml.
As the volume of glycol = 50 = volume of water
Hence, the number of moles of glycol = 
= 
= 
= 0.894 mol
Hence, number of moles of water = 
= 2.77
As glycol is dissolved in water.
So, the molality = 
= 17.9
Therefore, the expected freezing point = 
= 
Thus, we can conclude that the expected freezing point is .
<span>1) Humans have how many sets of teeth?
C) 4
2) Adults have how may permanent teeth?
B) 32
3) What type of food products make teeth stronger?
Cheese and Yogurt
4) What is the visible part of the tooth?
C) crown
5) What part of the tooth is harder than bone?
D) dentin
6) What part of the tooth is soft and contains the nerves?
A) pulp
7) What refers to the alignment of the teeth?
</span><span>
Occlusion</span><span>
8) The lower teeth protect what?
D) tongue
9) Malocclusion is the least common reason for referral to orthodontists.
False
10) Usually, malocclusion is hereditary.
True
11) Which type of malocclusion is commonly referred to as an overbite?
Class Two
12) Bacteria are living organisms than cause cavities.
True
13) What is the whitish film that grows on your teeth called?
Plaque
14) What is the best fighter of cavities?
Fluoride
Gingivitis is the inflammation of the
A) gums
16) Gingivitis is permanent.
False
17) Name 2 ways to fight gingivitis.
Proper Toothbrushing and Flossing
</span>Professional Dental Cleanings<span>
18) The cause of gum disease is
B) bacteria
19) Untreated, periodontitis will progress until your teeth loosen and fall out.
True
</span>
The enthalpy<span> of </span>solution<span>, </span>enthalpy<span> of dissolution, or heat of </span>solution<span> is the</span>enthalpy<span> change associated with the dissolution of a substance in a solvent at constant pressure resulting in infinite dilution. The </span>enthalpy<span> of </span>solution<span> is most often expressed in kJ/mol at constant temperature. </span>
