Answer:
Kb
Explanation:
The correct question is
What is Kb for N2H4 if the pH of a 0.158M solution of N2H5Cl is 4.5?
Solution-
N2H4Cl hydrolyses on addition of water
The reaction equation is as follows -
N2H4+ + H2O ----> N2H4 + H3O+
pH 
![[H+] = 10^{-pH} = 10^{-4.5}](https://tex.z-dn.net/?f=%5BH%2B%5D%20%3D%2010%5E%7B-pH%7D%20%3D%2010%5E%7B-4.5%7D)
Kb
Answer:
2.2 x 10²² molecules.
Explanation:
- Firstly, we need to calculate the no. of moles in (6.0 g) sodium phosphate:
<em>no. of moles = mass/molar mass </em>= (6.0 g)/(163.94 g/mol) = <em>0.0366 mol.</em>
- <em>It is known that every mole of a molecule contains Avogadro's number (6.022 x 10²³) of molecules.</em>
<em />
<u><em>using cross multiplication:</em></u>
1.0 mole of sodium phosphate contains → 6.022 x 10²³ molecules.
0.0366 mole of sodium phosphate contains → ??? molecules.
<em>∴ The no. of molecules in 6.0 g of sodium phosphate</em> = (6.022 x 10²³ molecules)(0.0366 mole)/(1.0 mole) = <em>2.2 x 10²² molecules.</em>
Answer:
Valence electrons or outer electrons are most important as they participate in bonding. The octet rule states that atoms gain, lose, or share valence electrons to have filled energy levels.. this gives atoms a stable configuration like that of the nearest noble gas.
Answer:
The correct answer is B.
Explanation:
The molecule of water has 2 atoms of hydrogen and 1 atom of oxygen.
The ratio of masses are given as:
This illustrates the law of definite proportions which is also known as law of constant compositions .
The law states that 'the elements combining to form compound always combine in a fixed ratio by their mass.'
Whereas :
Law of multiple proportion states that when two elements combine with each other to form more than one compounds , the mass of one element with respect to the fixed mass of another element are in ratio of small whole numbers.
Law of conservation of mass states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
In a balanced chemical reaction ,total mass on the reactant side must be equal to the total mass on the product side.
Law of conservation of energy states that energy can neither be created nor be destroyed but it can only be transformed from one form to another form.
Answer:
<h2>The sequence is; b, e, a, d, c
</h2>
Explanation:
1. In a decomposition reaction; One reactant is broken down into two or more than two products is called decomposition.
2. A combustion reaction; A fuel is combined with oxygen to produce carbon dioxide and water, this reaction is called combustion reaction.
3. A synthesis reaction; it occurs when two or more reactants combine to form one product is known as synthesis reaction.
4. Double Replacement Reaction; Two compounds react to form two different compounds is known as double Replacement Reaction.
5. A single replacement reaction; occurs when a compound reacts with an element to form a new compound , this reaction is called as single replacement reaction.
