Number of molecules in 1 dm³ Oxygen = 2.71 x 10²²
<h3>Further explanation</h3>
Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters/mol.
The mole is the number of particles contained in a substance
1 mol = 6.02.10²³
1 dm³ of oxygen = 1 L Oxygen

n=mol=0.045
No = 6.02.10²³

Mixture is a material made up of two or more different substances which are mixed. A mixture refers to the physical combination of two or more substances in which the identities are retained and are mixed in the form of solutions, suspensionsand colloids.[1][2]
Mixtures are one product of mechanically blending or mixing chemical substances such as elements and compounds, without chemical bonding or other chemical change, so that each ingredient substance retains its own chemical properties and makeup.[3]Despite that there are no chemical changes to its constituents, the physical properties of a mixture, such as its melting point, may differ from those of the components. Some mixtures can be separated into their components by using physical (mechanical or thermal) means. Azeotropes are one kind of mixture that usually pose considerable difficulties regarding the separation processes required to obtain their constituents (physical or chemical processes
PbCl2 and PbCl4
Empirical formula is when the molecular formula is reduced (each element) by the same number until you are unable to do so any further.
CH2O cannot be further reduced, but C3H6O3 can all be divided by 3 making it CH2O (same empirical formula)
Answer:
-484kJ
Explanation:
Carry out bond energy calculation
[6(C-H) + (C=O) +2(C-C)] - [(O-H) +7(C-H)+ (C-O) +2(C-C)]
Substitute the bond energy values = -484kJ
1. Who is the father of atomic theory?
Dalton
2. Who discovered the electron?
<span>Thomson
</span>
3. Who expressed particles by wave equations?
<span>Schrödinger
</span>
4. Who researched on radioactivity?
Curie
<span>5. Who discovered the "open spaces" model?
</span><span>Rutherford
</span>
6. Who applied quantum theory to atoms?
<span>Bohr</span>