Answer:
14 J of heat
Explanation:
Recall that the enthalpy of reaction is defined as the enthalpy change that occurs in a system when matter is transformed by a given chemical reaction, if all reactants and products are in their standard states. Here we have the heat of formation of six moles of the substance and we are expected to use it to obtain the the heat of formation of one mole of the compound and we can do that by simple proportion as shown below;
If 6 moles of the compound produces 84J of heat
1 mole of the substance will produce 1×84/6 = 14 J of heat
The answer is Joule. Kilograms and Grams is a unit for weight
Answer:
Explanation:
Chemical bonds are the forces that held the atoms in a molecules together. The strength of the bonds determine the some physical properties of material for example their hardness, solubility, boiling point, melting point etc. The stronger the bond , stronger will be the forces between them and it make difficult to separate the atoms.
There are three common type of bonding between atoms.
Ionic bonding
Covalent bonding
Metallic bonding
Ionic bonds are formed by complete transfer of electronic from one to another atoms. The compound having ionic bonds generally have moderate to high boiling points and melting point because of greater electrostatic interaction. Their electrical conductivity are high and these minerals tend to dissolve in water.
Covalent bonds are formed as a result of sharing of electrons between atoms. These compounds are insoluble , hard, having low melting and boiling points and have low conductivity.
The metallic bond is formed when metals are present. Due to loosely bound electrons of metals, electrons are shared with the other atoms. This is a type of covalent bond but it is not a true covalent bond. Th mobile electrons import great electrical conductivity in material. As this is a weak bond so these materials have low melting and boiling points.
<span>One reaction takes place in less time than the other.</span>
The moles of Al that are needed to react completely with 17 .5 moles of FeO is 11.67 moles
<u><em>calculation</em></u>
2Al +3 FeO → 3 Fe + Al₂O₃
The moles of Al is calculate using the mole ratio
That is; From equation above the mole ratio of Al :FeO is 2:3 therefore the moles of Al
= 17.5 moles x 2/3 = 11.67 moles
