1 mole of any substance contains Avogadro's number.
So, 1 mole of O2= 6.023x10^23 molecules
3 mole of O2= 6.023x10^23x3 molecules
= 1.8069x10^24 molecules
Each molecule of Oxygen has 2 atoms.
therefore,
1.8069x10^24 molecules= 1.8069x10^24 x 2 atoms
= 3.6138x10^24 atoms.
Answer:
Compound consist of molecules that are identical, this molecules are made up of atoms of two or more elements. An element is identified based on the atomic property of the element. Water as a compound is composed of 2 Hydrogen atom to 1 oxygen atom and the molecule is H2O.
Answer:
The expression to calculate the mass of the reactant is 
Explanation:
<em>The amount of heat released is equal to the amount of heat released per gram of reactant times the mass of the reactant.</em> To keep to coherence between units we need to transform 1,080 J to kJ. We do so with proportions:

Then,

1) Adding salt on the roads in the winter time,
2) Adding salt to the ice bath when making ice cream.
3) Mixing 2 substances when making coolant for a car.