There are a total of 6 hydrgen atoms
Explanation:
A chemical reaction where two chemical compounds exchange ions with each other is called a double displacement reaction.
Also, when an insoluble salt is formed due to chemical reaction between two chemical compounds is called a precipitation reaction.
For example, 
Here, ions are exchanged between the compounds 
and 
. Also, 
is the precipitate formed.
Answer:
A. 1.3 mol O₂
B. 10 mol H₂
C. 5 mol H₂O
Explanation:
2 H₂ + O₂ ⇒ 2 H₂O
According to the equation, for every 2 moles of hydrogen, 1 mole of oxygen is needed to react. Convert between moles of H₂ and moles of O₂ using this relationship.
A. (2.6 mol H₂) × (1 mol O₂)/(2 mol H₂) = 1.3 mol O₂
B. (5.0 mol O₂) × (2 mol H₂)/(1 mol O₂) = 10 mol H₂
According to the equation, for every mole of oxygen, 2 moles of water are produced. Use this relationship to convert.
C. (2.5 mol O₂) × (2 mol H₂O)/(1 mol O₂) = 5 mol H₂O
Answer:
1. 0.0500 moles K, 0.0250 moles Cr and 0.1000 moles O.
2. 9.00 moles ammonium ions are present.
Explanation:
1. In 1mol of K2CrO4 there are 2 moles of K, 1 mole of Cr and 4 moles of O.
The moles in 0.0250 moles K2CrO4 are:
0.0250mol * 2 = 0.0500 moles K
0.0250mol * 1 = 0.0250 moles Cr
0.0250mol * 4 = 0.1000 moles O
2. In 1 mole of (NH4)2CO3 there are 2 moles of ammonium ions, NH₄⁺.
In 4,50 moles are:
4.50 moles * 2 = 9.00 moles ammonium ions are present
Answer:
Mass Percent of Pencils = 7.20%
Explanation:
The mass percent can be calculated using the following equation. In this case, the "solute" is the pencil and the "solution" is the collection of pencils.
mass solute
Mass Percent = ------------------------ x 100%
mass solution
9.540 g (pencil)
Mass Percent = -------------------------------------------- x 100%
132.456 g (pencil collection)
Mass Percent = 7.20%
