Noble gasses I think I could be wrong tho
D i had taken the test already.
The helium in a glass model is a gas
KCO₂
K₂C₂O₄
Explanation:
Given parameters:
Percent composition:
K = 47%
C = 14.5%
O = 38.5%
Molar mass of compound = 166.22g/mol
Unknown:
Empirical formula of compound = ?
Molecular formula of compound = ?
Solution:
The empirical formula of a compound is its simplest formula. Here is how to solve for it:
K C O
Percent
composition 47 14.5 38.5
Molar mass 39 12 16
Number
of moles 47/39 14.5/12 38.5/16
moles 1.205 1.208 2.4
Dividing
by smallest 1.205/1.205 1.208/1.205 2.4/1.205
1 1 2
Empirical formula KCO₂
Molecular formula
This is the actual combination of the atoms:
Molecular formula = ( empirical formula of KCO₂)ₙ
Molar mass of empirical formula = 39 + 12 + 2(16) = 83g/mol
n factor = 
n factor =
= 2
Molecular formula of compound = ( KCO₂)₂ = K₂C₂O₄
Learn more:
Empirical formula brainly.com/question/2790794
#learnwithBrainly
Answer:
0.01981 gallons.
Explanation:
In this problem, we need to convert 75 mL of water to gallons.
We know that, 1 gallon = 3785.41 mL
To convert 75 mL to gallons, we must use to the unitary method such that,
1 mL = (1/3785.41) gallon
So,

So, there are 0.01981 gallons in 75 mL of water.