Answer: An igneous rock that cools rapidly is made of really small mineral crystals.
Explanation:
The layers inside the earth are hot enough to melt a rock. The liquid or molten rock is known as magma.
When a molten rock cools and solidifies, it results in the formation of an igneous rock.
The slow cooling of magma will result in the formation of an igneous rock with large crystals. Whereas, rapid cooling of lava will result in the formation of an igneous rock with small crystals.
Thus, it can be concluded that an igneous rock that cools rapidly is made of really small mineral crystals.
The second one is, "<span>Be careful to present only objective facts"</span>
Answer:
C(graphite) → C(diamond), ΔH = - 0.45 kcal
CH4 + 2O2 → CO2 + 2H2O + 212,800 cal
Explanation:
C(graphite) → C(diamond), ΔH = - 0.45 kcal
CH4 + 2O2 → CO2 + 2H2O + 212,800 cal
These reactions are exothermic reaction because heat is evolved.
The energy changes occur during the bonds formation and bonds breaking.
There are two types of reaction endothermic and exothermic reaction.
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
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
Answer:
589.8 kJ/mol
Explanation:
Let's consider the process in which <em>the most loosely bound electron from each atom in a mole atom of gaseous calcium is removed.</em>
Ca(g) + Energy ⇒ Ca¹⁺(g) + 1 e⁻
The energy involved in this process is known as First Ionization Energy. The First Ionization Energy for calcium is 589.8 kJ/mol.
