Molality is obtained by dividing the number of moles of solute by the mass in kilogram of the solvent. None of the dimensions is dependent in temperature. On the other hand, molarity is obtained by dividing the number of moles of solute by the volume in liters of the solution. Volume is temperature dependent.
Answer:
This question is incomplete but the completed question is below
Which Of These Species Is Most Likely To Be A Lewis Acid And Is Also Least Likely To Be A Brønsted Acid? (A) NH4⁺ (B) BF₃ (C) H₂O (D) OH⁻
The correct option is B
Explanation:
A lewis acid is a substance that accepts (or is capable of accepting) a pair of electrons. For example BF₃, while a lewis base is a substance that donates (or is capable of donating) a pair of electrons. For example OH⁻.
If we take a look at the boron (B) in BF₃, it has 3 electrons on it's outermost shell, each of which are bonded to flourine and can still accept a pair of electrons (lone pair). <u>This makes it very likely to be a lewis acid</u>.
Bronsted lowry acid is a substance that donates or can donate a proton or H⁺ (for example HCl) while bronsted lowry base is a substance that accepts or can accept a proton or H⁺ (for example NH₃).
<u>BF₃ cannot donate a proton or H⁺ hence it is least likely to be called a bronsted acid.</u>
Answer:
Molarity= 1.69M
Explanation:
m= 14.8, Mm= 35, V= 0.25dm3, C= ?
Moles = m/M= C×V
Substitute and Simplify
m/M= C×V
14.8/35= C×0.25
C= 1.69M
Answer:
4.8 grams of H₂ will be produced if 175g of HCI are allowed to react completely with sodium
Explanation:
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) you can see that the following amounts in moles of each compound react and are produced:
- HCl: 2 moles
- Na: 1 mole
- NaCl: 2 moles
- H₂: 1 mole
You know the following masses of each element:
- H: 1 g/mole
- Cl: 35.45 g/mole
- Na: 23 g/mole
So, the molar mass of each compound participating in the reaction is:
- HCl: 1 g/mole + 35.45 g/mole= 36.45 g/mole
- Na: 23 g/mole
- NaCl: 23 g/mole + 35.45 g/mole= 58.45 g/mole
- H₂: 2* 1 g/mole= 2 g/mole
Then, by stoichiometry of the reaction, the following amounts in grams of each of the compounds participating in the reaction react and are produced:
- HCl: 2 moles* 36.45 g/mole= 72.9 g
- Na: 1 mole* 23 g/mole= 23 g
- NaCl: 2 moles* 58.45 g/mole= 116.9 g
- H₂: 1 mole* 2 g/mole= 2 g
So, a rule of three applies as follows: if by stoichiometry, when reacting 72.9 grams of HCl 2 grams of H₂ are formed, when reacting 175 grams of HCl how much mass of H₂ will be formed?

mass of H₂= 4.8 g
<u><em>4.8 grams of H₂ will be produced if 175g of HCI are allowed to react completely with sodium</em></u>