* Calcium chloride can be prepared by the reaction of calcium with chlorine gas. Figure 9 shows some properties of calcium chlorine and calcium chloride
ability to conduct electricity
substance
relative melting
point
when solid
when molten
calcium
high
good
good
chlorine
low
poor
poor
calcium chloride
high
poor
good
Figure 9
Explain, in terms of bonding and structure, why the properties of the product,
calcium chloride, are different from the properties of the reactants, calcium
and chlorine

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i  

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.