Answer:
2
Explanation:
In two reactions energy is released.
1) C₆H₁₂O₆ + 6O₂ → 6H₂O + 6CO₂ + heat
It is cellular respiration reaction.It involves the breakdown of glucose molecule in the presence of oxygen to yield large amount of energy. Water and carbon dioxide are also produced as a byproduct.
Glucose + oxygen → carbon dioxide + water + 38ATP
2) 2H₂ + O₂ → 2H₂O ΔH = -486 kj/mol
The given reaction is formation of water. In this reaction oxygen and hydrogen react to form water and 486 kj/mol is also released.
The reaction in which heat is released is called exothermic reaction.
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
When the balanced equation for this reaction is:
2Fe + 3H2O → Fe2O3 + 3H2
and according to the vapour pressure formula:
PV= nRT
when we have P is the vapor pressure of H2O= 0.121 atm
and V is the volume of H2O = 4.5 L
and T in Kelvin = 52.5 +273 = 325.5 K
R= 0.08205 atm-L/g mol-K
So we can get n H2O
So, by substitution:
n H2O = PV/RT
= (0.121*4.5)/(0.08205 * 325.5) = 0.02038 gmol
n Fe2O3 = 0.02038 * (1Fe2O3/ 3H2O) = 0.00679 gmol
Note: we get (1FeO3/3H2O) ratio from the balanced equation.
we can get the Mass of Fe2O3 from this formula:
Mass = number of moles * molecular weight
when we have a molecular weight of Fe2O3 = 159.7
= 0.00679 * 159.7 = 1.084 g
∴ 1.084 gm of Fe2O3 will produced
Answer: B
Explanation:
protons are positive,
electrons are negative,
and neutrons are neutral.
the amount of electrons to protons is always the same in a balanced atom.
electrons can be removed creating "ions" which is simply an unbalanced atom. removing protons would result in a different type of atom or element.
Answer:
Iodine
Explanation:
It's in the same group as chlorine.
Answer:
Rb
Explanation:
This is because they are in the same group which means they share similar properties.
