Answer:
Conservation of Energy and Mass
The law of conservation of mass states that in a chemical reaction mass is neither created nor destroyed. ... Similarly, the law of conservation of energy states that the amount of energy is neither created nor destroyed.
As the atomic mass of iron is 55.847u
We say that it is the mass of one mole of iron.
By formula it can be find by
No.of mole=mass in g/molar mass
Mass in gram = no.of mole x molar mass
No.of mole =1
Molar mass = 55.847g
Mass in gram = 1x55.847
= 55.847g of Fe
Answer:
1= 2H₂ + O₂ → 2H₂O
2=CaCo₃ + heat → CaO +CO₂
3=CH₄ + 2O₂ → CO₂ +2H₂O
4=HCl + NaOH → NaCl + H₂O
Explanation:
1 = Simple composition
The formation of water molecule is simple composition reaction. In this reaction two hydrogen atoms react with one oxygen atom and form one water molecules.
2H₂ + O₂ → 2H₂O
The amount of energy released is -285.83 KJ/mol. It is exothermic reaction.
2 = Simple decomposition reaction:
The break down of sodium hydrogen carbonate into sodium carbonate, carbondioxide and water is decomposition reaction. The decomposition reactions re mostly endothermic, because compound required energy to break.
2NaHCO₃ + heat → Na₂CO₃ + H₂O + CO₂
It is endothermic reaction.
Another example is:
CaCo₃ + heat → CaO +CO₂
3 = Combustion reaction
Consider the combustion of methane:
CH₄ + 2O₂ → CO₂ +2H₂O
The burning of methane is exothermic. The combustion reactions are exothermic because when fuel are burns they gives energy.
4 = Neutralization reaction
The neutralization reactions are those in which acid and base react to form the salt and the water. Some neutralization reactions are exothermic because they release heat. e.g
Consider the neutralization reaction of HCl and NaOH.
HCl + NaOH → NaCl + H₂O
Explanation:
A compound is defined as follows.
- Compounds are pure substance.
- The atoms bonded in a compound are in specific proportion.
- A compound is formed by chemical combination.
- For a compound, melting point and boiling point is defined.
A mixture is defined as follows.
- Mixtures are impure substance.
- The bonded atoms in a mixture are in any proportion.
- A mixture is formed by physical combination.
- For a mixture, melting point and boiling point is not defined.
On changing the amount of one substance will affect the formation of compound as a compound requires atoms to be bonded in a specific proportion. Whereas changing the amount of one substance will not affect the formation of mixtures as atoms can be bonded in any proportion in a mixture.
Answer: You should learn the symbols for the eight most abundant elements in the Earth's crust (Oxygen (O), Silicon (Si), Aluminum (Al), Calcium (Ca), Iron (Fe), Magnesium (Mg), Sodium (Na), and Potassium (K) .
Explanation: