A. The molecules of solids are close together and compact, liquids are spread out but not too far apart, and gas molecules are really far apart.
B. Increase in temperature causes pressure to go up. Decrease in temperature cause pressure to go down
Dipole interactions are observed in covalent bonds. In ionic bonding, permanent transfer of electrons occurs and due to this dipole-dipole interactions are not observed. In covalent bonding, electron cloud is shared between 2 atoms. If this electron cloud is not shared equally between them, polarities are formed in a molecule. And hence we say that the molecule is polar. For a molecule to be polar, there should be electronegativity difference between them. Atom with greater electronegative attracts electron cloud more towards itself whereas atom with lesser electronegative attracts electron cloud less. But there is no permanent transfer of electrons. Due to this electronegativity differences, atom with more electronegative gains partial negative charge and atom with lesser electronegative value gains partial positive charge. The charge is partial because there is no complete transfer of electrons.
Correct Question:
A chemist measures the enthalpy change ΔH during the following reaction: Fe(s) + 2HCl(g)-->FeCl2(s) + H2 ΔH=-157.0 kJ. Use this information to complete the table below. Round each of your answers to the nearest kJ/mol
Answer:
-314 kJ
+628 kJ
+157 kJ
Explanation:
The enthalpy change of a reaction measures the amount of heat that is lost or gained by it. If ΔH >0 the heat is gained, and the reaction is called endothermic, if ΔH<0, the heat is lost, and the reaction is called exothermic.
If the reaction is inverted, the value of ΔH is inverted too (the opposite endothermic reaction is exothermic), and if the reaction is multiplied by a constant, ΔH will be multiplied by it too.
1) 2Fe(s) + 4HCl --> 2FeCl2(s) + 2H2(g)
This reaction is the product of the given reaction by 2, so
ΔH = 2*(-157) = -314 kJ
2) 4FeCl2(s) + 4H2(g) --> 4Fe(s) + 8HCl(g)
This reaction is the inverted reaction given multiplied by 4, so
ΔH = 4*(157) = +628 kJ
3) FeCl2(s) + H2(g) --> Fe(s) + 2HCl
This reaction is the inverted reaction given, so
ΔH = +157 kJ
Answer:
The equation is balanced
Explanation:
NaCl (aq) + AgNO3(aq) ––> AgCl (s) + NaNO3 (aq)
NaCl (aq) + AgNO3 (aq)
Na = 1 , Cl=1 , Ag = 1 , No3= 1
AgCl (s) + NaNO3 (aq)
Ag = 1 , Cl=1 , Na = 1 , No3= 1
