Ozone is made up of 3 atoms of Oxygen and present in stratosphere of our atmosphere. It prevents us from "Ultraviolet rays" of Sunlight so it is an important form of oxygen or us
Hope this helps!
        
             
        
        
        
Answer:
The number of moles of  xenon are 1.69 mol.
Explanation:
Given data:
Number of moles of xenon = ?
Volume of gas = 37.8 L
Temperature = 273 K
Pressure = 1 atm
Solution:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K  
T = temperature in kelvin
Now we will put the values in formula.
1 atm × 37.8 L = n ×  0.0821 atm.L/ mol.K   ×273 K
37.8 atm.L =  n × 22.413 atm.L/ mol.
n = 37.8 atm.L /  22.413 atm.L/ mol.
n = 1.69 mol
The number of moles of  xenon are 1.69.
 
        
             
        
        
        
All animals can be dangerous and they would fight for their family. (This might be wrong)
 
        
             
        
        
        
At STP one mol weighs 22.4L
Moles of O_2
1 mol.O_2 can create 2mol water
moles of water
Volume of water
 
        
                    
             
        
        
        
A qualitative test for sulfate in alum crystals using ionic reactions of barium chloride (BaCl2) is given Ba²⁺(aq) + SO₄²⁻ (aq)  →   BaSO₄(s).
<h3>What is qualitative test?</h3>
Qualitative test measures changes in color, melting point, odor, reactivity, radioactivity, boiling point, bubble production, and precipitation of the sample.
<h3>Qualitative test for sulfate in alum crystals </h3>
When an aqueous solution of a barium salt (BaCl₂) is mixed with an aqueous solution containing sulfate, a white precipitate of insoluble BaSO₄ forms according to the net ionic equation given below;
Ba²⁺(aq) + SO₄²⁻ (aq)  →   BaSO₄(s)
Thus, a qualitative test for sulfate in alum crystals using ionic reactions of barium chloride (BaCl2) is given Ba²⁺(aq) + SO₄²⁻ (aq)  →   BaSO₄(s).
Learn more about qualitative test here: brainly.com/question/2109763
#SPJ1